Environmental Impact Assessment

Project TA No.: 9242-REG

Status: Initial Draft (revised)

Date: February 2020

Samoa: Alaoa Multi-purpose Dam Project

Volume 1: EIA Report

Prepared by Electric Power Corporation of Samoa

This environmental impact assessment is a document of the borrower. The views expressed herein do not necessarily represent those of the ADB’s Board of Directors, Management, or staff, and may be preliminary in nature.

In preparing any country program or strategy, financing any project, or by making any designation of or reference to a particular territory or geographic area in this document, the Asian Development Bank does not intend to make any judgments as to the legal or other status of any territory or area.

Alaoa Multi-Purpose Dam Project - Environmental Impact Assessment Revision No: 3.1 E307132 10-Feb-20

Document information

Document title Alaoa Multi-Purpose Dam Project Initial Environmental Impact Assessment Client organisation Asian Development Bank Client contact Woo Lee ConsultDM number E307132 Project Manager Richard Herweynen Project number P513660

Revision history Revision 3.0

Revision description Initial draft EIA document issued to ADB

Prepared by Entura Team: Andrew Taylor William Elvey Cedric Schuster Tim O’Meara Sam Sesega Other support: Pilgrim J. Stirnemann R. L. Reviewed by Andrew Taylor Approved by Richard Herweynen

(name) (signature) (date) Woo Lee Asian Development Bank Distributed to Jean Williams Asian Development Bank

(name) (organisation) (date)

Revision 3.1: Including comments of ADB (23-Jan-20) and revisions 10-Feb-20

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Contents

1 Introduction 1 1.1 Overview of the document 1 1.2 Definition of the project area 3 1.3 Confidence in the safety of a dam against failure 7 1.4 Ecological importance of the project Area 7 1.4.1 Avifauna - ma’oma’o / mao 7 1.4.2 Avifauna - Manumea 8

2 Legal, Administrative and Policy Framework 10 2.1 Institutional Arrangements 10 2.1.1 Executing and implementing agencies 10 2.1.2 Other relevant institutions 10 2.2 Country safeguard system 12 2.2.1 Lands, Surveys and Environment Act 1989 12 2.2.2 Planning and Urban Management Act 2004 12 2.2.3 Environmental Impact Assessment Regulations 2007 12 2.2.4 Water Permit and Water Management Act 14 2.2.5 Forest Act 14 2.2.6 Security and Emergency Disaster and Emergency Management Act 2007 14 2.2.7 Protection of Wildlife Regulations 2004 15 2.3 Policies for Samoa 15 2.3.1 Cultural and Natural Heritage Conservation Policy 2004 15 2.3.2 Planning for Climate Change Policy 15 2.3.3 Policy Statement on Biological Diversity 15 2.3.4 Samoa Codes of Environmental Practice 2006 15 2.3.5 Statement of Economic Strategy (SES) 2000 – 2001 16 2.3.6 Strategy for the Development of Samoa 2017 - 2020 16 2.3.7 Energy Sector Plan 2012 - 2016 17 2.4 Relevant International Agreements 18 2.5 Relevance of Legal, Policy, and Administrative Frameworks 19 2.6 Safeguard Policy Statement 19 2.6.1 Environmental Requirements 19

3 Description of the Project 21 3.1 Project components 21 3.2 Proposed project delivery mechanism 25

4 Alternatives 26 4.1 Overview 26 4.2 Technological - Alternative to a dam 26 4.3 Location and site alternatives 26 4.3.1 Different dam types and sizes 26 4.3.2 Hydropower options 28

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4.3.3 Storage options 28 4.4 Ecological considerations 29 4.4.1 Environmental Flow 29 4.4.2 Species migration past Samsoni Weir 29 4.5 No project 30

5 Description of Existing Environment (Baseline) 31 5.1 Physical Environment 31 5.1.1 Geography and topography 31 5.1.2 Geology and Soils 32 5.1.3 Climate 35 5.1.4 Climate Change 38 5.1.5 Hydrology 40 5.1.6 Tectonic setting / Seismology 45 5.1.7 Geomorphology 47 5.1.8 River sediment charatcter, transport and deposition 52 5.2 Biological Environment 53 5.2.1 Overview of ecology 53 5.2.2 Overview of flora 53 5.2.3 Overview of avifauna and fauna 54 5.2.4 Overview of protected areas and key biodiversity areas 54 5.2.5 Apia Catchment KBA and the project area 56 5.2.6 Habitat in the project area 60 5.2.7 Terrestrial habitat value and threat status 64 5.2.8 Avifauna – Mao 65 5.2.9 Avifauna - Manumea 68 5.2.10 Other terrestrial species 70 5.2.11 Aquatic fauna 70 5.2.12 Previous aquatic surveys of the Vaisigano River 71 5.2.13 Ecology and status of migratory climbing species 72 5.2.14 Migration requirements 78 5.2.15 Priority biodiversity: natural and critical habitat 80 5.3 Environmental Flow 84 5.3.1 Current hydropower development in the Vaisigano River catchment 84 5.3.2 Changes in flow with the new flood protection dam 87 5.4 Socio-economic Environment 90 5.4.1 Population and demography 90 5.4.2 Communities in the project area 92 5.4.3 Livelihoods and Employment 93 5.4.4 Overview of land use and land ownership 93 5.4.5 Land tenure in the project area 94 5.4.6 Economy and economic infrastructure 96 5.4.7 Cultural heritage and resources 98 5.4.8 Ambient noise 99 5.4.9 Traffic movements 103

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6 Consultation and Information Disclosure 105 6.1 Overview 105 6.2 Stakeholder Identification and Engagement 105 6.3 Consultations Undertaken 106 6.4 Information disclosure 109 6.5 Process for Consultation During Implementation 111 6.6 Grievance redress mechanism 112 6.6.1 Overview 112 6.6.2 GRM during construction phase 113 6.7 Outcomes and Conclusions of the Consultations 116 6.7.1 Benefits 116 6.7.2 Costs/adverse impacts 116

7 Assessment of Impacts 117 7.1 Overview of Assessment 117 7.1.1 A structured approach to critical habitat impact assessment 118 7.1.2 Risk matrix approach for impact assessment 119 7.2 Pre-construction impacts 120 7.2.1 Potential impacts on terrestrial critical habitat 120 7.2.2 Potential impacts on aquatic critical habitat 121 7.2.3 Potential impacts on natural habitat 122 7.2.4 Residual impacts on terrestrial critical habitat 136 7.2.5 Residual impacts on aquatic critical habitat 137 7.2.6 No net loss/net gain approach 143 7.2.7 Updating the EIA, development consent application and bid & contract documentation 147 7.2.8 Identifying suitable material sources 148 7.2.9 Biosecurity and introduction of invasive and/or alien species 149 7.2.10 Worker code of conduct 149 7.3 Construction Impacts on Physical Environment 150 7.3.1 Degradation of landscapes and soil erosion 150 7.3.2 Soils, geology and hydrogeology 151 7.3.3 Climate change – reservoir GHG emissions 152 7.3.4 Climate change – adaptation and resilience of the Project 154 7.3.5 Natural hazards 157 7.3.6 Air quality – dust and other emissions 158 7.3.7 Hydrology and water quality 160 7.3.8 Borrow pits and quarry sites 161 7.3.9 Waste and Materials 162 7.4 Construction Impacts on Biological Environment 164 7.4.1 Biodiversity - potential impacts on critical and natural habitat 164 7.4.2 Vegetation removal and forest clearance during construction 164 7.5 Construction Impacts on Socio-economic Environment 165 7.5.1 Labour conditions 165 7.5.2 Workplace and Community Health and Safety 165 7.5.3 Utilities and Infrastructure 167 7.5.4 Site Construction Access Routes 167

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7.5.5 Construction camps 167 7.5.6 Construction Noise 168 7.5.7 Vibration 173 7.5.8 Cultural and physical resources 177 7.6 Operation Impacts 178 7.6.1 Operation impacts on the physical environment 178 7.6.2 Operation impacts on biological environment 180 7.6.3 Operation impacts on socio-economic environment 181

8 Environmental Management Plan 182 8.1 Introduction 182 8.2 Institutional Responsibilities 182 8.2.1 Project Management Unit of Electric Power Corporation 182 8.2.2 Construction supervision consultant and supervising engineer 183 8.2.3 Lenders Technical Advisor 183 8.2.4 Design and build contractor 183 8.3 Framework of Environmental Plans 185 8.3.1 Environmental management system 185 8.3.2 Framework of the plans 185 8.3.3 Environmental reporting requirements 195 8.4 Pre-Construction EMP 195 8.5 Construction Phase EMP 199 8.6 Operational Phase EMP 217 8.7 Estimated Costs for Environmental and Social Protection Measures 226

9 Conclusions and Recommendations 229 9.1 Conclusions 229 9.1.1 Critical Habitat issues 229 9.1.2 Environmental Flow issues 231 9.2 Concluding remarks 231 9.3 Requirements and Recommendations 232 9.4 Provisions for Grant Agreement 233

References 236

Appendices

Appendix 1 – Environmental documents reviewed in the preparation of this EIA 256

Appendix 2 – Project specific studies prepared as part of EIA process 257

Appendix 4 – Data utilized & calculations undertaken in GHG emissions estimate for the Project 259

Appendix 5 – Construction noise calculations 261

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List of Figures

Figure ES1: Four Branches of Vaisigano River and Location of Alaoa Dam and UNDP flood walls xiii Figure ES2: 3D representation of Dam impoundment and hydro-power station xiii Figure 1.1: Location of Samoa and project area 1 Figure 1.2: Project area for the Project and Apia Catchment key biodiversity area 5 Figure 1.3: Plan of Works – Dam, inundated area, penstock and hydropower station 3 Figure 1.4: Alaoa Dam Project - schematic of existing and post project situation 4 Figure 3.1: The four sub catchments in the Vasigano catchment 20 Figure 3.2: Location of flood protection walls in Apia – in relation to project 24 Figure 3.3: General Arrangement of the preferred dam option 24 Figure 3.4: How water will be stored behind dam for flood protection, water supply and powerError! Bookmark not defined.25 Figure 4.1: The two dam site options considered 27 Figure 5.1: Vaisigano catchment 31 Figure 5.2: Geological map of Upolu 33 Figure 5.3: Digitised version of soil map of Upolu covering the Vaisigano River catchment. 34 Figure 5.4: Mean monthly rainfall distributions - 3 rainfall stations within or near Vaisigano River catchment 35 Figure 5.5: Annual rainfall distributions - 5 rainfall stations within or near Vaisigano River catchment 36 Figure 5.6: Distribution of wind speed by month for Lanafala 36 Figure 5.7: Distribution of wind speed by direction for Lanafala 36 Figure 5.8: El Nino Southern Oscillation effects in the Pacific 39 Figure 5.9: Daily Mean flow 2.5 km d/s Samasoni weir for modelled natural & current scenarios 40 Figure 5.10: Flow duration curve 2.5 km d/s of Samasoni weir - modelled natural and current scenarios 41 Figure 5.11: Monthly low flow indices 2.5 km d/s of Samasoni weir - modelled natural and current scenarios 42 Figure 5.12: Partial duration series flood frequency for Vaisigano River 2.5 km d/s of Samasoni Weir 43 Figure 5.13: Annual flow & annual peak hourly discharge for the Vaisigano River 2.5 km d/s of Samasoni Weir 44 Figure 5.14: Flow health deviation indicator scores for Vaisigano River 2.5 km d/s of Samasoni Weir - modelled current scenario relative to natural scenario 44 Figure 5.15: Tectonic setting of Samoa 445 Figure 5.16: PGA hazard curve adopted for Alaoa dam (POE based on 50 years) 46 Figure 5.17: Topography of Upolu, Samoa, showing location of Vaisigano River catchment 47 Figure 5.18: Topography of the area in the vicinity of the proposed Alaoa reservoir 48 Figure 5.19: Slopes of Vaisigano River catchment and area in the vicinity of the proposed Alaoa reservoir 50 Figure 5.20: Time series of selected historical aerial photographs of Apia Bay 51 Figure 5.21: Terrestrial Key Biodiversity Areas and endemic vegetation for Upolu and Savai’i 55 Figure 5.22: Apia Catchment Key Biodiversity Area 56 Figure 5.23: Project area of influence 58 Figure 5.24: Vegetation types in the project area 61 Figure 5.25: Avifauna – location of five acoustic recording devices in the Project area 66 Figure 5.26: Birds detected by acoustic devices 67

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Figure 5.27: Recent Manumea observations around project 69 Figure 5.28: Schematic of aquatic area of analysis showing areas of critical, natural and modified habitat 82 Figure 5.29: Existing hydro-power infrastructure and issues in the Vaisigano River catchment 85 Figure 5.30: Existing hydro-power infrastructure, proposed new dam and issues in Vaisigano River catchment 88 Figure 5.31: Population distribution in Upolu 91 Figure 5.32: Population density on Upolu 91 Figure 5.33: Location of noise monitoring site and points 101 Figure 5.34: Breakdown of traffic types on Cross Island Road 103 Figure 6.1: Simplified flow chart of the grievance redress mechanism 112 Figure 6.2: Grievance redress mechanism process 114 Figure 6.3: Contractor - construction phase GRM process at site level 115 Figure 7.1: Risk matrix (likelihood and consequence) used for impact assessment 119 Figure 7.2: Decision tree - if facility passes or fails mitigation component under Climate Bonds Initiative 152 Figure 8.1: Organisation plan for construction phase staffing 184 Figure 8.2: How a contractor CEMP evolves from the EIA and EMP 198 Figure 8.3: Sub-plans for the CEMP identified in this EIA document 200

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List of Tables Table 2.1: EIA Regulations (2007) Categories of Project 13 Table 3.1: Key characteristics of the project 23 Table 5.1: Slopes in the Vaisigano watershed 32 Table 5.2: Projected temperature change under different emissions scenarios 39 Table 5.3: Hazard spectra adopted for Alaoa dam 46 Table 5.4: Apia Catchment Key Biodiversity Area 57 Table 5.5: Ecosystem types within the survey sites 59 Table 5.6: Partial species list for mixed plantation: plantation with some large indigenous and exotics 62 Table 5.7 Partial species list for secondary forest: forest with a mixture of indigenous and exotics 65 Table 5.8: Threat classification listing for all species of concern 65 Table 5.9: Freshwater fish species recorded from Samoa Islands (Samoa and American Samoa) - IUCN Red List status and habitat preferences 74 Table 5.10: Freshwater crustacean species recorded from Samoa Islands (Samoa and American Samoa) - IUCN Red list status and habitat preferences 77 Table 5.11: Fish species recorded during IEE in 2013 79 Table 5.12: Crustacean species recorded during IEE in 2013 779 Table 5.13: Summary of critical habitat-qualifying biodiversity in the Project area 81 Table 5.14: Electricity production by Island and source 2017-2018 97 Table 5.15: Existing hydro power capacity in Upolu. 97 Table 5.16: Summary of ambient noise levels recorded on site in October 2018 102 Table 5.17: Summary of traffic counts on access roads in October 2018 104 Table 6.1: Consultations and meetings held on the Project during EIA due diligence 2018-2019 110 Table 6.2: Consultation and information disclosure during detailed design and implementation 111 Table 7.1: Impact assessment for critical habitat-qualifying biodiversity in the Project area 123 Table 7.2: Mitigation and management measures for critical habitat-qualifying biodiversity and natural habitat 131 Table 7.3: Summary of specific measures to protect critical habitat (with costs) 132 Table 7.4: Quantification of Project impacts on terrestrial vegetation 137 Table 7.5: Residual impacts after mitigation for critical habitat-qualifying biodiversity 139 Table 7.6: Summary of approach to residual impacts (including costs) 142 Table 7.7: Power density calculation for Alaoa Multi-purpose Dam 153 Table 7.8: Water supply reliability over 50 year model run 154 Table 7.9: Peak flows, in m3/s, at Samasoni and Vaisigano under dam/no dam conditions for historic and future climate 155 Table 7.10: AEP (1 in X) of flood peak at Lower Vaisigano under dam and no dam conditions for historic and projected future climate 155 Table 7.11 Equivalent AEP (1 in X) of flood peak at Lower Vaisigano under current conditions 156 Table 7.12: Damages at Apia due to flooding (USD) 156 Table 7.13: Description of construction waste material and approximate volumes of waste 163 Table 7.14: Noise standards for construction 169 Table 7.15: Equipment likely to be used during major construction activities 170

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Table 7.16: Construction noise impact summary by activity 172 Table 7.17: Guideline vibration damage potential threshold criteria 175 Table 7.18: Vibration source amplitudes for construction equipment 175 Table 8.1: Environmental Management Plan – detailed design and pre-construction stage 196 Table 8.2: Provisional contents list for a CEMP and guidance notes on provisions 201 Table 8.3: Environmental Management Plan – construction stage 203 Table 8.4: Environmental Management Plan – operational stage 218 Table 8.5: Monitoring plan 223 Table 8.6: Costs associated with environmental protection elements of the Project 225

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Contents of EIA Volume 2

Annex A – Noise Monitoring Report

Annex B – Terrestrial Biodiversity and Habitat Assessment

Annex C – Aquatic Biodiversity and Habitat Assessment

Annex D – Environmental Flow Assessment

Annex E – Geomorphic Impact Assessment

Annex F – Archaeological Survey

Annex G - Land Acquisition / Resettlement Plan

Annex H – Stakeholders Consultation and Participation Report

Annex I – Climate Change

Annex J - Assessment of Ecological Effects: Birds and Bats

Annex K – Critical Habitat Assessment

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Abbreviations

ADB Asian Development Bank AMMP Avifauna Management and Monitoring Plan Part of BMMP AMDP Alaoa Multi-purpose Dam Project AOA Area of analysis Used in natural/critical habitat assessment BMMP Biodiversity management and monitoring plan BOP Biodiversity offsetting plan CEAR Comprehensive Environmental Assessment Report Under CSS CEMP Construction environmental plan Contract document COEP Codes of Environmental Practice 2006 Samoa standards (under PUMA) CSC Construction supervision consultant Supporting the PMU CSS Country safeguard system DEC Division of Environment Conservation Division of MNRE DOF Division of Forestry Division of MNRE DWR Division of Water Resources Division of MNRE EIA Environmental Impact Assessment EMP Environmental Management Plan EPC Electric Power Corporation Implementing agency GRM Grievance redress mechanism Complaints process IUCN International Union for Conservation of Nature LTA Lenders technical advisor(s) MAFF Ministry of Agriculture, Forestry and Fisheries MCIL Ministry of Commerce Industry and Labour MFAT Ministry of Foreign Affairs and Trade MNRE Ministry of Natural Resources and Environment MOF Ministry of Finance Executing agency MOH Ministry of Health MWCSD Ministry of Women, Community & Social Development MWTI Ministry of Works, Transport and Infrastructure NEMS National Environment Management Strategy NBSAP National Biodiversity Strategy and Action Plan PEAR Preliminary Environmental Assessment Report PMU Project Management Unit, EPC PUMA Planning and Urban Management Agency Under MWTI RCC Roller compacted concrete Dam construction technique SPS Safeguard Policy Statement ADB policy document 2009 SWA Samoa Water Authority WCC Worker code of conduct Part of the CEMP

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Glossary

Critical habitat (defined as per SPS) A subset of both natural and modified habitat that deserves particular attention. Critical habitat includes areas with high biodiversity value, including habitat required for the survival of critically endangered or endangered species; areas having special significance for endemic or restricted-range species; sites that are critical for the survival of migratory species; areas supporting globally significant concentrations or numbers of individuals of congregatory species; areas with unique assemblages of species or that are associated with key evolutionary processes or provide key ecosystem services; and areas having biodiversity of significant social, economic, or cultural importance to local communities. Environmental flow Environmental flows describe the quantity, timing, and quality of water flows required to sustain freshwater and estuarine ecosystems and the human livelihoods and well-being that depend on these ecosystems. Key Biodiversity Area A site of critical importance for the conservation of globally important biodiversity. The project area is contained within the Apia Catchments KBA. However, it is noted that while the KBA site has no legal protection it still triggers one of the criteria for defining an area of critical habitat as per the SPS. Levelized Cost of Energy The net present value of the unit-cost of electrical energy over the lifetime of the generating asset. It is a first-order economic assessment of the cost competitiveness of an electricity-generating system that incorporates all costs over its lifetime: initial investment, operations and maintenance, cost of fuel, cost of capital. (Wikipedia) Natural habitat (defined as per SPS) Land and water areas where the biological communities are formed largely by native plant and animal species, and where human activity has not essentially modified the area’s primary ecological functions. Significant conversion or degradation of habitat (i) the elimination or severe diminution of the integrity of a habitat (defined as per SPS) caused by a major, long-term change in land or water use; or (ii) the modification of a habitat that substantially reduces the habitat’s ability to maintain viable populations of its native species.

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Executive summary

1. This executive summary summarises the findings of the environmental impact assessment (EIA) carried out for the Alaoa Multi-Purpose Dam Project in Samoa. The Alaoa Multi-Purpose Dam is proposed to be sited behind the Samoa capital, Apia, in the Vaisigano River catchment.

2. The physical characteristics of the Vaisigano River catchment means that during extreme storm events there is rapid build-up and substantial water runoff in the river which has led to historic physical damage to property downstream, loss of life, damage to infrastructure and flooding across Apia.

3. The Alaoa Multi-Purpose Dam Project can assist in the regulation of flows during storm events to reduce damage to infrastructure (water treatment works immediately down-stream from the proposed dam site and existing hydropower stations on the Vaisigano River) and loss of property and life. In addition, the project will provide water supply and electric power generation benefits.

4. The Project Implementation Unit of the Electric Power Corporation of Samoa has been identified as the implementing agency for the proposal to construct a 60m high Dam (the Alaoa Multi-purpose dam project) on the Vaisigano River catchment behind the Samoa capital of Apia. The primary objective of the project is to provide flood protection to Government infrastructure sited in the upper catchment1 and protection of people and property in the middle and lower catchments. In addition, water retained behind the dam will provide security of water supply in periods of low rainfall and a new hydropower plant, constructed as part of the project, will generate electric power further reducing Samoa’s reliance on fossil fuels (diesel fuel) used to power conventional electric power generating equipment.

5. Though completely independent of the UNDP flood alleviation project—walls and embankments being constructed on the lower reaches of the Vaisigano River—the flooding regulation provided by the Project will greatly assist in reducing likelihood and frequency of overtopping of the structures constructed under the UNDP project.

6. This EIA has been carried out for the project under the requirements of the Asian Development Bank (ADB) Safeguards Policy Statement 2009 (SPS) and Samoa’s environmental and social legislation and permitting procedures. Due to the impact of the dam on natural habitat, loss of 20ha, ADB has determined that the Project is Category A for environmental, as per the SPS, requiring the production of an EIA document. The draft EIA document will be disclosed on the ADB website for a period of 120 days for public examination.

Project Description

7. The project comprises the construction and operation of a 60m high dam on two of the four Vaisigano River sub-catchments. The dam will be constructed to contain flows in the eastern and middle eastern sub-catchments of the Vaisigano River watershed. Flows in the central and western sub-catchments will be unaffected (as shown in Figure ES 1). The feasibility study consultant (Entura) has been appointed and conducted a technical review of different arrangements to provide flood protection; water supply and hydropower generation and determined that a roller compacted concrete (RCC) design, is the most suitable option in terms of safety, efficiency and cost to protect the citizens of Apia and Samoa’s goal for resilience to natural disasters such as flooding, self-sufficiency in water supply and sustainable electric power generation (Figure ES 2) . The funding for the project will be in the form of grants from ADB and other sources. The precise arrangement for the grants is still under discussion and negotiation.

1. Government infrastructure includes a water treatment works the existing Alaoa Hydropower station, The Fala o Fee Hydropower station and the Samsoni Hydropower station

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Figure ES 1: Four branches of Vaisigano River and location of Alaoa Dam and UNDP flood walls

Figure ES 2: 3D representation of Dam impoundment and hydro-power station

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Alternatives

8. The “No Action” alternative is defined as a decision not to undertake the proposed dam construction. The “No Action” alternative means that there will be no flood protection provided to the infrastructure, people and property in the Vaisigano Catchment. Analysis of climate change carried out as part of this project suggests that major storm events are likely to increase in frequency and that more extreme storm events are likely, therefore a ‘no project scenario’ would have major social and economic consequences on the population of Apia.

9. The Vaisigano catchment is made up of four sub catchments: Western, Central; Middle Eastern and Eastern. Due to the location of existing infrastructure it is not possible to build a dam to contain all catchment flows and the study has only focused on flows generated in the Middle Eastern and Eastern Catchments (about 50% of the total catchment). In determining the most efficient place to construct the dam for the middle eastern and eastern catchments the design consultants looked at options of (i) only considering the middle eastern catchment, leaving the smaller eastern catchment free flowing; or (ii) putting the dam downstream from the confluence (joining point) of the eastern and middle eastern streams. It was determined that the option to contain both the middle eastern and eastern streams gave the most cost- effective benefits in terms of protection.

10. The damming of a stream permanently alters the water flow in the existing river. This loss of an existing “environmental flow” was investigated in detail as part of the study, specifically the impact on aquatic flora and fauna. The original concept for the hydropower station was a site immediately downstream from the existing Alaoa hydropower station, approximately 400 m downstream from the proposed dam site (see Figure ES 2). It was determined that the loss of permanent flow from the dam site to the confluence of the western and central sub-catchments was not acceptable in terms of ecological considerations and the site of the hydropower station has been relocated to the foot of the dam. This makes it possible to maintain an “environmental flow” of water in the existing river from the dam to Apia Bay (the marine environment).

Land Ownership, Land Acquisition and Resettlement

11. No permanent land acquisition of any kind (voluntary or involuntary) is expected under the current project scope and design. Nearly all proposed project works that fall under the scope of this EIA study are located within a single piece of government (public) land totalling 1,851 hectares that covers substantially all of the middle and upper watershed of the Vaisigano River. Records show that the government acquired the land underlying the entire project area in 1921 in a manner that accords with ADB SPS and with applicable national laws.

12. During stakeholder consultation meetings, at least three families claimed that they own part of the project area as customary land. In each case, the government has demonstrated that the land in question is public land and that the people who are living on or otherwise using the land are doing so illegally. Whether or not the present claimants once sincerely believed that they own the land in question as customary land, all the claimants have now seen the documentary evidence to the contrary, and they have not provided any evidence to support their own claims.

13. EPC has determined that Alaoa Road is the only viable access road to the project site. Alaoa Road is a public secondary road that runs in a south-easterly direction from Cross Island Road to the water treatment plant on the Vaisigano River downstream of the proposed dam site. The top 950 metres of Alaoa Road (“upper Alaoa Road”) is tar sealed to a low standard with a sealed width varying from 5 to 6 metres. The remaining 400 metres of the roadway (“lower Alaoa Road”) is unpaved dirt going down a steep hill to the flat bottomland where the water treatment plant is located. At that point, the terminus of Alaoa Road is about 1.0 km due north (downstream) of the proposed dam site.

14. ADB has designated the project Category B for involuntary resettlement.

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Key Environmental Impacts

15. There are no human pollution sources identified within the project footprint. A project specific environmental baseline established and confirmed low levels of air, noise and water pollution.

16. The draft EIA findings are that all the potential adverse environmental impacts of the proposed final design can be prevented, mitigated and/or offset to ensure that SPS requirements can be met and positive impacts strengthened as a result of design and implementation of mitigation and enhancement measures identified in the environmental management plan (EMP) and other plans—biodiversity management and monitoring plan (BMMP) and biodiversity offsetting plan (BOP), currently under preparation. Public consultations held in 2018-2019 suggested strong public support for the project particularly the alleviation of flooding impacts. Though concerns were raised about the safety of the dam based on media reporting of dam failures in other countries; the selected design is considered to be safe and tested over many years of service in other countries and the dam will be designed to the most robust of design standards. A dam safety analysis has been undertaken as part of the feasibility study.

Natural and Critical Habitat Assessment

17. The Project footprint overlaps a mosaic of natural and modified habitat, comprising secondary forest – including non-native species – and mixed subsistence farming. The Project is on the edge of a large forested landscape. Downstream rivers have been degraded by cumulative impacts from existing weirs, but upstream rivers remain mostly natural habitat. The Natural and Critical Habitat Assessment identified this landscape to be possible or actual critical habitat for: one globally critically endangered and one endangered bird (Tooth-billed Pigeon and Mao); two endangered lizards (Olive Small-scaled Skink and Samoa Skink); three least concern, one data deficient and one not evaluated fish species (Fat-snout Goby, Stenogobius genivittatus, Green Riffle Goby, Stiphodon hydroreibatus, and Schismatogobius tuimanua); an Endangered snail (Thaumatodon hystricelloides); one critically endangered and one endangered palm (Drymophloeus samoensis and Clinostigma samoense); and the Apia Catchments Key Biodiversity Area.

18. Without mitigation, the Project could have high impacts on some of this critical habitat-qualifying biodiversity, owing to forest loss and introduction, spread of invasive alien species, and/or prevention of migration of fish above the dam. Additional risks are direct degradation of forest and river habitats, displacement of existing agriculture in the Project area, disturbance of birds during construction, hunting of birds by construction workers, and Project-induced access leading to increased longer-term hunting and forest loss/degradation.

19. The Natural and Critical Habitat Assessment identified mitigation, management and offsetting measures necessary to reduce residual impacts on critical habitat-qualifying biodiversity to levels in line with the SPS. This mitigation is anticipated to cost c.US$50,000 while offsetting costs are anticipated to be in the range of US$4-8 million. The development and design of the BMMP and BOP will provide more accurate costs.

20. Key mitigation measures are:

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• Taking care to avoid introduction of new invasive species to, and spread of existing invasive species within, the Project area. • Prior to finalization of project designs and any clearance, identify, clearly mark and map all mature native trees, to facilitate avoidance and minimization; • Minimize clearance of native vegetation at the Project site and around associated roads and other infrastructure; using already cleared or modified areas for construction wherever possible. Prioritize avoidance of Ficus and Dysoxylum trees (which may provide seasonal food sources for Tooth-billed Pigeon), and attempt to relocate any of these which cannot be avoided; • Replant native vegetation (including Dysoxylum species) in any temporarily disturbed areas; • Regularly maintain and inspect/certificate all vehicles, equipment and machinery to ensure that noise levels conform to national standards; • Avoid construction during the most sensitive Mao breeding period (June-August inclusive); • Avoid construction within 150 m of an occupied Tooth-billed Pigeon or Mao nests; • Educate local people on the dangers of deliberate introductions of invasive species.

21. After these mitigation measures, and the offsetting measures to be designed and implemented through the BOP, the Project is predicted to achieve no net loss for most critical habitat-qualifying biodiversity. Residual impacts on this priority biodiversity are expected to remain measurable by the Project operations phase, particularly direct loss of terrestrial and aquatic habitat, and degradation of upstream habitats by prevention of aquatic species’ migration past the dam, and downstream degradation of aquatic habitat and fragmentation of terrestrial habitat owing to the Project access roads and reservoir.

22. Given these residual impacts, and the wider context of substantial cumulative impacts on forests and forest-dwelling species in Samoa, and on rivers and aquatic life in the Vaisigano watershed, the Project is planning to make a positive contribution that will offset these residual impacts. In coming months, a detailed BMMP and BOP will be developed. This will help to more closely define requirements and costs. The biodiversity offsetting will achieve no net loss ofr biodiversity in alignment with ADB safeguard requirements for projects in areas of critical habitat (ADB 2009).2

23. In summary, this Project will comply with the SPS because it is not located within a legally protected area and will put in place mitigation and offsets to address impacts on natural habitat that result in:

• no measurable adverse impacts on critical habitat that could impair its ability to function; • no reduction in the population of any recognized endangered or critically endangered species; and • overall benefits substantially outweighing the environmental costs.

2. Specifically, the project aims to restore up to 240 ha of forest elsewhere in the Vaisigano River watershed (which will also support the Project’s flood control goals) and to control key invasive species in those areas (at a provisional cost of c.US$155,000- 320,000/year), to establish appropriate environmental flows from existing weirs in the watershed in order to facilitate aquatic species’ migration and improve river quality, and to support translocation of some Mao to American Samoa (at a cost of c.US$250,000). In total, costs of a net gain approach are thus estimated to be c.US$4.2-8.3 million.

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Environmental Flow

24. The Vaisigano River provides habitat for six migratory fish and seven migratory crustacean species, including reaches within the proposed inundation zone and in the reaches upstream of the inundation zone in the east and middle-east branches.

25. All of the migratory species present have to move between freshwater and marine habitats to complete their life cycle. The reaches assessed as modified and natural habitat have been assessed as providing critical habitat for five species of migratory fish

26. Regulation has significantly reduced the flow regime in the five kilometres of the east branch downstream the offtake for the Fale ole Fee Power Scheme; the 1.3 kilometre reach of the middle branch downstream from the offtake for the Alaoa Scheme; and, the 4.2 kilometre reach of the main branch downstream from Samasoni Weir to the tailrace for Samasoni Power Scheme. These reaches experience zero flow for extended periods each year, provide no aquatic habitat and reduce the pathways for migratory species to move up and downstream.

27. The objectives of the environmental flow mitigation is to restore flow lost to the current hydro-power schemes and to offset the impacts of the new project by improving migration opportunities into the lower (main branch), mid (main, middle and west branches) and upper reaches (middle and west branches) of the catchment. If the environmental flow is implemented, operation of the new dam is predicted to result in no net loss of biodiversity in the catchment.

28. It is proposed to release a permanent baseflow from Samasoni Weir and from the offtake weir on the middle branch. A monthly fresh rule is also proposed from these locations to increase the frequency and duration that higher flows are delivered downstream.

29. The release of a permanent baseflow (and monthly pulses) from these reaches will provide the following environmental benefits:

• Restore permanent aquatic habitat to 4.2 kilometres of the main channel downstream from the Samasoni Weir and the final 1.3 kilometre reach of the middle branch before it joins the west branch. • Allow populations of goby, eel, shrimp, prawn and macroinvertebrate to establish in these reaches • Restore connectivity and migratory pathways from the sea to the upper reaches of the catchment. Specifically, a permanent baseflow will increase opportunities for: • The downstream migration of larval gobies, prawns and shrimps to reach the sea • Adult eels to migrate downstream to the sea to breed • Upstream migration of juvenile gobies, eels, prawns and shrimps from the lower reaches and the sea • Provide social benefits for increased access to permanent flowing reaches for washing and recreational fishing.

30. The existing Samasoni weir directs all flow to a header tank of the Samasoni power station. Currently, downstream flow only occurs during flood events. A penstock valve can be opened to provide downstream flow, but this still represents a barrier for aquatic species migration. Therefore, it is proposed to construct a “fish ladder” on the face of the Samasoni weir to allow fish passage without the physical need for the penstock valve to be operated.

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Construction Phase Environmental Impacts

31. Air quality. During construction, air quality may be degraded by a range of operational activities including; exhaust emissions from construction machinery; rock processing and concrete manufacture; and dust generated from haul roads, unpaved roads, exposed soils, material stockpiles, etc. This can lead to health impacts to locals and impacts to ecology and crops. But these impacts are readily mitigated by simple interventions regarded as being “good site practise”.

32. Soils. Potential soil contamination is a possibility in the construction phase resulting from poor management of fuel, oil and other hazardous liquids used during the project works. Again, these impacts are readily mitigated by simple interventions regarded as being “good site practise”.

33. Surface water. Impacts to surface water and groundwater could occur through improper operation of construction camps and associated manufacturing areas including crushing and grading, concrete and, asphalt production. Poor construction management at the dam site and close to surface watercourses could also lead to pollution incidents. Technical water can be sourced from rivers in the Project area without impacting on existing inhabitants. These potential impacts are readily mitigated by simple interventions regarded as being “good site practise”.

34. Groundwater. Impacts to groundwater include spills and leaks of hazardous liquids used at construction sites and manufacturing area. Mitigation will be through good site practices implemented by the contractor and checked during periodic audit. Specific mitigation includes forming bunds to guide unpolluted water around works areas, silt traps and bunds downstream of site and sumps for settlement before discharge, drip traps and good maintenance of equipment.

35. Natural hazards. The dam and access roads are located in a region that is seismically active and the dam and its associated structures have been designed in accordance with the appropriate design standards. At construction site level, the contractor will prepare a Slope Stabilisation Plan and Water Resources Management Plan to prevent construction activities increasing flood risk.

36. Construction camps. Construction camps are a temporary land use change with potential impacts on air quality (dust); water quality (poor sanitation) and improper solid wastes and effluent; together with issues related to unwanted construction worker fraternisation (cultural differences, HIV / AIDS, etc.) However, given the proximity to the urban area of Apia it is unlikely that a large construction camp with overnight accommodation and extensive ablution facilities will be required. Rather, the small international management team can be accommodated in existing accommodation in Apia and the locally sourced skilled, semi-skilled and unskilled workers will be accommodated at their home base and travel into work during the working day.

37. Physical and cultural resources. An archaeological survey concluded that there were no physical cultural resources within the Project area. While unlikely that physical cultural resources will be uncovered during works, a chance find process, identified in the archaeological survey assessment report, is included in the EMP.

Operation Phase Environmental Impacts

38. Noise, air and water quality. No noise, air or water pollution sources are identified for the operational phase of the project. No impact requiring mitigation has been identified.

39. Environmental flows. The Project has the opportunity to restore good quality habitat through release of environmental flows for existing schemes in the catchment.

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Mitigation and Management Actions

40. Design, construction and operation phase management plans have been derived and presented in a set of site-specific environmental management plans. The EIA document includes these environmental management plans (EMP) identifying (i) mitigation measures for potential environmental impacts encountered during implementation, (ii) an environmental monitoring program to ensure that mitigation is in place and operating effectively; and (iii) identification of the responsible entities for mitigation, monitoring, and reporting. The construction phase EMP will be included in project bidding documents for the project for adoption by the contractors, though it will be a contract requirement that the construction contractor will be required to develop and gain approval for their own site and construction methodology-specific construction environmental management plan (CEMP) including site-specific plans and sub-plans .

Stakeholder Engagement

41. During the due diligence process for the project (July 2018 to date) the consultants and the Project Management Unit (PMU) conducted consultations with potentially affected households and wider communities and stakeholders.

42. Those attending received information about the Project resettlement plan, bidding process and expected time for the beginning of the works and the establishment of the grievance redress mechanism (GRM) and details on the GRM procedure. Participants were supportive of the project and shared their concerns and suggestions on issues such as dam safety amongst other issues.

43. Costs associated with environmental protection during design, construction and operation phases (excluding offsetting measures to be developed and costed through the BOP) are provisionally costed at US$1.1M.

Implementation

44. The EMP, its mitigation and monitoring programs identified in the EIA will be included within the Project Bidding Documents for works. This ensures that all potential bidders are aware of the environmental requirements of the Project and its associated environmental costs.

45. The project bidding documents will state that the contractor will be responsible for the development and implementation of the EMP through their own construction EMP (CEMP) which will be based on the EMP in the EIA and reflect the construction programme and approach they will adopt for the works. The CEMP will adopt all of the conditions of the EMP adding site specific elements that are not currently known e.g. The location and layout of contractor construction camps, lay down areas, borrow areas (if required), disposal areas and the operation measures for each and how their construction processes will ensure that the project is implemented in an environmentally acceptable manner.

46. The EMP and all its requirements will be included in the contract, making implementation of the EMP a legal requirement under the contract. The contractor’s CEMP will be reviewed by the PMU (supported by the construction supervision consultant) and ADB and advice given that the CEMP may be approved by the PMU and the Engineer. The PMU and the Engineer will monitor the contractor’s compliance with the approved CEMP, through routine monitoring by their national and international environmental specialists. To manage and ensure compliance with the CEMP the contractor will recruit an environmental management officer and a health and safety officer (EMO and HSO) to monitor and report Project activities throughout the Project construction phase.

47. A GRM has been prepared as part of the EIA for the Project. The GRM provides a structure for stakeholders to make complaints and a mechanism for the complaints to be resolved both locally and centrally.

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Conclusions

48. Environmental and social benefits of the Project outweigh the adverse impacts, which range minor and largely temporary inconveniences (physical and social impacts) to high magnitude impacts that require mitigation and offsetting measures (ecological impacts). The impacts can be reduced through implementation of the pre-construction measures and construction and operation phase EMPs. Additional biodiversity mitigation and offsetting plans are being prepared and will be implemented and monitored. The draft EIA including its EMP is considered sufficient to meet the environmental assessment requirements of ADB and the Government of Samoa. Following the public disclosure period, and revision of the EIA responded to comments, the EIA will be submitted as part of the application for development consent for the Project.

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1 Introduction

1.1 Overview of the document

1. This is the environmental impact assessment (EIA) for the Alaoa Multi-Purpose Dam Project (AMDP). The Alaoa Dam is proposed to be sited behind the Samoa capital, Apia on the Vaisigano River catchment.

Figure 1.1: Location of Samoa and project area in Vaisigano catchment

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2. The physical characteristics of the Vaisigano River catchment mean that during extreme storm events there is rapid build-up and substantial water runoff in the river which has led to physical damage to property downstream, loss of life, damage to infrastructure and flooding across Apia. In response to these flooding events downtown, a separate project is underway to channelise the downstream end of Vaisigano River to constrain storm flows and reduce damage downstream. The Alaoa Multi-Purpose Dam Project can assist in the regulation of flows during storm events and in addition provide water supply and electric power generation benefits.

3. The EIA document is structured around nine reporting chapters four supporting appendices (Volume 1) and eleven Annexes (EIA volume 2). In this document appendices are defined as information referenced from and supporting the main text, but its inclusion would adversely affect the flow of the text. An annex is a defined as stand-alone document that is summarised in the main text. The nine reporting chapters / sections of the EIA are:

• Section 1 – introduces the project providing an overview of the project and the key areas of concern that will be addressed in the document. • Section 2 –sets out the legal, administrative and policy framework that has defined the need and approach to the Environmental Impact Assessment. It discusses both the requirements of Samoan legislation and policy and those of the Asian Development Bank the International Financing Institution (IFI) for the project. • Section 3 –describes the physical details of the project, the delivery mechanism timeframe and outline costs. • Section 4 - analyses the alternatives to the project including a “no project” scenario and the different options that have been considered in reaching the preferred option i.e. different construction options, dam locations, and ecological implications of Alaoa dam development. • Section 5 – sets out the existing environmental baseline including biophysical feature, ecological and socio-economic. • Section 6 – discusses the consultations carried out for the project to disseminate information to the stakeholders and interested parties. It also includes sections on the land ownership, resettlement and compensation. The Vaisigano watershed was acquired by the New Zealand colonial administrator in 1921 and therefore no permanent land acquisition is required. During the EIA a number of interested parties have indicated that they have claims on land within the project boundary. The process of addressing the validity of these claims is set out in the section. • Section 7 – is the assessment of impacts and where impact is identified the approach to mitigation. This section draws on the detail from eleven dedicated technical studies carried out as a part of the preparation of this EIA and presented, in full, in Volume 2 of this EIA – Annexes. • Section 8 – are the environmental management plans (EMP) that will guide interested parties during the detailed design; construction and operation phases of eth project. It sets out specific requirements to elements that must be addressed and included in the detailed design, the issues that a contractor must address during the construction phase and the ongoing management issues that the implementing agency must address in the operational life of the project. The section includes costs directly attributable to satisfy and address the environmental legislation and environmental and social safeguard policy requirements of the Government of Samoa and the Asian Development Bank. • Section 9 is a summary and conclusion of the findings of the EIA document.

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• Volume 2: presents the 11 documents that are the project specific, stand-alone studies of specific environmental aspects: (i) noise baseline and traffic counts; (ii) terrestrial biodiversity and habitat; (iii) aquatic biodiversity and habitat; (iv) environmental flow; (v) geomorphology; (vi) archaeology and cultural heritage; (vii) land acquisition and resettlement; (viii) stakeholder consultations; (ix) climate change; (x) dedicated report on invertebrates; and (xi) natural and critical habitat assessment.

1.2 Definition of the project area

4. The project area consists of a 59.6-metre-high dam wall located on the combined eastern branch of the Vaisigano River 6.5 kilometres upstream from where the river discharges into Apia Bay. At full supply level (FSL) the dam will inundate 0.2 km2 (20 hectares) of riverbed, valley floor, and hillslope habitats in the middle region of the Vaisigano Catchment, including a 1.3 kilometre length of the middle-eastern branch and a 1.1 kilometre reach of the eastern branch of the Vaisigano River. The project area is in the Vaisigano River catchment which is within the wider Apia Catchments key biodiversity area (KBA) see Figure 1.2. The area of inundation is less than two percent of the catchment area upstream of the proposed dam.

5. A penstock will run 360 metres downstream from an outlet on the dam along the right bank of the river to the new power station. The existing Alaoa Power Station discharges into the Vaisigano River 80 metres upstream from the proposed new power station but is located on the opposite bank (Figure 1.3); it is now proposed that the power station will be located immediately below the proposed dam to address ecological considerations (maintaining an ecological flow in the stream immediately below the dam.

Figure 1.3: Plan of Works – Dam, inundated area, penstock and hydropower station

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6. Figure 1.4 is a schematic showing the current and post project situation.

Figure 1.4: Alaoa Dam Project - schematic of existing and post project situation

7. It is assumed that material for construction of the dam will be obtained from within the inundated area, removing the need for offsite borrow areas. The contractor may base his administration buildings outside the inundation area, but the footprint will be small, and impacts can be managed through normal site practices. It has been assumed that storage and processing areas will be located inside the inundation area. Transport of imported construction materials and construction plant, between the Port and the construction site, will be on the existing road network.

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Figure 1.2: Project area for Alaoa Multi-Purpose Dam Project and Apia catchment key biodiversity area (KBA)

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1.3 Confidence in the safety of a dam against failure

8. A catastrophic failure of a dam (i.e. sudden collapse) will have major consequences downstream i.e. flooding, loss of life, damage to vital infrastructure (electric power generation equipment, water treatment works, etc.) In the engineering feasibility study the dam has been classified as a “High Hazard Dam” and has therefore been designed for appropriate flood and earthquake loadings and includes a risk assessment approach3 in assessing the preferred design.

9. The selected type of dam assessed in this EIA is a roller compacted concrete (RCC) dam. The RCC dam is a concrete gravity structure. Concrete dams are considered to one of the safest types of dam above other types of dam, e.g. an embankment dam.4

10. There will be further detailed design to confirm the precise arrangements for the dam construction and operation and it is recommended that all necessary dam safety documentation / plans required for a high hazard dam shall be included in a Dam Safety Emergency Plan that would be a requirement of the contract for constructing the dam.

1.4 Ecological importance of the project Area

11. The impoundment behind the dam will remove an area of 20ha of existing habitat comprising abandoned cultivated land, river and steep hillsides that feature native trees and invasive species. The inundated area will remove habitat occupied or used by terrestrial and aquatic flora and fauna. Two species of avifauna are identified here. A project’s category is determined by the category of its most environmentally sensitive component, including direct, indirect, cumulative, and induced impacts in the project’s area of influence. The Project has been assigned Category A for environment following the SPS.

1.4.1 Avifauna - ma’oma’o / mao

12. The ma’oma’o or mao is endemic to Samoa. The species is listed as endangered by the IUCN. Mao were previously found on both Upolu and Savaii in the upland and foothill forests (Watling, 2004). The mao was also historically found on Tutuila, American Samoa, but it is now locally extinct on all American Samoan islands. The species was last collected from Tutuila in 1924 and the last unconfirmed report of the bird was in 1977 (Watling, 2004). The reason for the local extinction is not known.

13. Following cyclones Ofa and Val a decline in the number and distribution of Mao were noted. This decline is likely to be linked to the severe storm damage to critical habitat. During a rapid biodiversity survey in 2014 biorap, out of 135 random point counts over four areas in both Savaii and Upolu mao were recorded twice (ICCRIFS 2014). Both points were within the Lake Lanoto’o reserve, an extremely small area which can only maintain a small number of territories (R. Stirnemann, pers. obs). These results suggest that mao distribution is more limited than previously thought. Mao populations occur predominantly on village owned land outside of protected areas.

3. Based on the Australian Risk Management Standard AS/NZS 4360:2004 – see chapter 21 of the project Technical Feasibility Study (Entura Oct 2018) 4. A combination of soil, sand, clay, or rock with an impervious core.

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Plate 2: Male Mao and Mao – ringed and with transmitter Plates 1.1: Male Mao and male Mao ringed and with transmitter (for tracking)

14. The current population size of the mao is unknown. The IUCN lists an estimated population of 375- 1,499 individuals. The recovery plan (MNRE, 2006) suggests that mao may be present in smaller numbers than the manumea, a species which has recently been classified as critically endangered.

15. The exact cause of the decline of the mao in Samoa has been linked loss of habitat and the presence of invasive species, such as rats, which predate the chicks and may result in mortality of the breeding female (Stirnemann et al. 2016). Slow life history traits, such as a small clutch size and low maximum annual reproductive success, also contribute to the vulnerability of this species (Stirnemann et al. 2016). At maximum, only a single chick is produced each year (Stirnemann et al. 2016). The chick is dependent on the mother bird for 2-2.5 months post fledging (Stirnemann et al. 2016).

16. Nest predation by rats is a problem, particularly in modified sites near plantations where rat numbers are higher (Butler & Stirnemann, 2013). Mao only lay a single egg and are not known to have more than one brood in a season, as a result the annual fecundity is low (Stirnemann, 2016). In the Vaisigano and Lake Lanoto’o catchments a reproductive success rate of 0.33 chicks per adult female per year was observed. This was reduced to 0.125 chicks per female near plantations where predation of rats is high. If rat numbers are reduced and nests are actively protected (through trapping and rat rings around trees), reproductive success and adult and fledgling survival increases (Stirnemann pers com). Cats may also predate juveniles which spend time on the ground and females are vulnerable to predation while on the nest (Stirnemann et al. 2016).

17. Mao are absent from logged sites but can occupy modified habitat such as plantations where large trees still remain. The Samoan government identified six key sites for mao conservation. The Vaisigano catchment is identified as one of five sites for mao conservation on Upolu, and one of five “first priority” sites in Samoa.

18. In Malololelei intensive pest control activity has now been occurring for over two years. Mao have been responding well to this conservation effort. Early results suggest a possible spill over of mao outside the target pest control area into the surrounding habitat.

1.4.2 Avifauna - Manumea

19. The manumea is endemic to Samoa and is the country’s national bird. Manumea is listed as critically endangered by the IUCN. This is the highest threat ranking for extant species in the wild. The threat ranking for manumea was raised in 2014 from a former classification of endangered because the population was estimated to be smaller than previously thought. Low numbers of recent records and a decreasing number of sightings suggest that the population is now extremely small.

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20. In the 1980s, Dr Ulf Beichle, who studied the manumea in the 1980s and 1990s, estimated the population of manumea was to be approximately 4800-7200 birds (MNRE, 2006). During this period flocks of Manumea could still be seen.

21. Over the last few decades large areas of forest in Samoa were deforested by logging activity and also heavily impacted by cyclones (Cyclones Ofa, 1990 and Val 1991). In 2000, a population of fewer than 2,500 mature Manumea were estimated. The current population is considered to be approximately 300-100 birds.

22. Between 1978 to 2000, birds were recorded in many locations from near sea level to the uplands of Upolu, Savai’i and on Nuutele Island (MNRE, 2006). Recent surveys indicate that manumea are now rare (Butler & Stirnemann, 2013). A survey in the Savai’i uplands took place with the hope that the area was a possible stronghold for the species (Butler & Stirnemann, 2013). These surveys suggest manumea may not occur in high numbers in the Savai’i uplands.

23. In 2005-2006, manumea were recorded at 10 out of 24 sites surveyed (MNRE, 2006). Between 2011 and 2019, 48 possible sightings of manumea were recorded from scientists and local people. Several sightings of manumea occurred within or near the water catchments above Apia (Butler & Stirnemann, 2013), including flying across Cross Island Road and in Malololelei. Confirmed sightings in the Vaisigano catchment have been made near Magiagi, in Malololelei, flying over cross island road. Furthermore, Moeumu Uili and Fialelei Enoka from MNRE confirmed and photographed a juvenile Manumea at Salelologa (MNRE, 2014). The juvenile had just fledged the nest confirming breeding in this area.

24. The Manumea was once considered to be a bird of upland montane forests (MNRE, 2006). However, recent observations suggest that lowland areas maybe critical for this species. The manumea has been observed in mature and secondary forest including in forest edge habitat, along forest roads and sometimes visiting clearings where large native fruiting trees remain. The species has been recorded from sea-level to 947m (MNRE, 2006). However, it is likely the species elevational distribution is seasonal reflecting fruiting of key tree species.

25. Manumea distribution has been closely linked to native fruit-bearing trees such as Dysoxylum (Dysoxylum maoto, D. samoense and D. huntii) and aoa or banyan trees (Ficus obliqua). Manumea play a vital ecological role by distributing the seeds of native Samoan trees (Butler & Stirnemann, 2013). Very little is known about the breeding biology of the Manumea. Old records and Samoan sayings suggest it may nest close to the ground.

26. Threats to manumea include hunting, predation by feral cats, rats, pigs and loss of habitat, and the effects of climate change, including increased risk of cyclones and droughts (MNRE, 2006, Stirnemann pers com). Loss of habitat can also occur through forest loss caused by the effects of invasive plants [smothering forest trees] such as rubber trees replacing native trees. In the 1800s cats were first identified as a threat to the species when they were observed killing adult birds. Rats may also prey on eggs and chicks. Foraging and nesting low to the ground would put eggs, chicks and adult birds at increased risk of predation.

27. Manumea was traditionally a highly esteemed source of food, especially for the high Chiefs in Samoa (Stirnemann, 2017). Recent surveys, however, have shown that in recent times hunting by local people focuses on the Lupe or Pacific Pigeon which is preferred for its meat. Present days when manumea are shot it is predominantly as bycatch to the Lupe or Pacific Pigeon (Stirnemann, 2017).

28. The Manumea Recovery Plan (MNRE, 2006) identified eight key sites for conservation of manumea, comprising of five sites on Upolu and three sites on Savai’i. The locations included upland and lowland sites, although the Vaisigano catchment was not identified as a key site. A more recent report (MNRE, 2014) has identified only three key sites for conservation, consisting of two lowland sites on Savai’i and one upland site on Upolu. These are Aopo forest; Faala to Salelologa; and the Vaisigano catchment and Lake Lanoto’o. The map also highlights the upper, central and western Vaisigano catchment (MNRE, 2014).

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2 Legal, Administrative and Policy Framework

29. This section provides an overview of strategies / legal norms and guidelines on environmental assessment in Samoa which have been followed for other implemented projects in Samoa. This section also identifies the relevant strategies and policies of Samoa and the Asian Development Bank (ADB). The project will require the implementation of all national and international environmental and social policies guidelines and performance requirements

2.1 Institutional Arrangements

2.1.1 Executing and implementing agencies

30. This project will be executed under the Ministry of Finance (MOF).

31. The implementing agency is Electric Power Corporation (EPC). The EPC is sole provider of electricity in Samoa with a core function to generate, transmit, distribute and sell electricity. Non-core functions include:

• Design of power systems • Installation and maintenance of generation equipment, • Installation of some distribution and utilization equipment • Repair of motor vehicles, • Perform Government Community Service Obligations,

32. Initially its functions were carried out through the Ministry of Works Transport and Infrastructure. But it became independent (corporate) body in 2011 but retaining strong links to the Ministry.

33. The day to day work of the project will be carried out by the Project Management Unit (PMU) of the Electric Power Corporation

2.1.2 Other relevant institutions

34. There other relevant institutions that will be directly concerned or involved in the project, as described below.

35. Ministry of Natural Resources and Environment. The Ministry of Natural Resources and Environment (MNRE) has several principal divisions covering all aspects of the environment: i) Disaster Management, ii) Environment and Conservation, iii) Forest Division, iv) Global Environment Facility, v) Land management, vi) Meteorology, vii) PUMA, viii) Renewable Energy, ix) Water Resources.

36. The main divisions concerned by the project are:

• The PUMA (Planning and Urban Management • Division of Environment Conservation • Division of Water Resources • Division of Forestry

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37. The Planning and Urban Management Agency. The Planning and Urban Management Agency (PUMA) is responsible for implementing the Planning and Urban Management Act 2004 and reviews and assesses the EIA being submitted by the proponent.

38. This process ensures that all the relevant information is included to ensure that an informed decision is easily made about the proposed development. The EIA must be in accordance with the EIA Regulations 2007. The review of EIA reports for major developments is usually submitted to the Board for a decision while sometimes the Agency may process and make its decision on the approval of EIAs for minor developments.

39. Division of Water Resources. The Division of Water Resources (DWR) in MNRE controls the water resources or the watershed under the Water Resources Management Act 2008-2011 58. The domain of the sector includes the regulation, development and use of all freshwater resources as well as the receiving coastal waters in Samoa. Over the years, sanitation has evolved as a priority issue in the sector. It is responsible for water resource management and includes policy and regulation, watershed management, hydrological and hydro-geological investigation, and water quantity monitoring. This Division has the appropriate equipment for water management and monitoring.

40. Division of Forestry issues permits to harvest trees (Forestry Harvesting Permit) – which will be required as part of clearance activities for the reservoir area.

41. Ministry of Works, Transport and Infrastructure. The Ministry of Works, Transport and Infrastructure (MWTI) regulates the construction of buildings and issue building permits, to construct, maintain and manage the public assets, in the project case, the construction of access roads. Each Government Department or agency is responsible for the construction and maintenance of its buildings The Ministry of Works, Transport and Infrastructure (MWTI) is responsible for drainage and storm water management, especially in relation to the development of road infrastructure and power lines. –

42. Ministry of Women, Culture and Social Development. Any land acquisition needed under this project will have social implications and transformations and each case will have to refer to this Ministry. The Ministry of Women, Culture and Social Development (MWCSD) through its Internal Affairs Division, is facilitating in the provision and improvement of water supply and sanitation services in Village Managed Schemes (VMS), and assisting MNRE in water resources management at community level. –

43. Ministry of Commerce, Industry and Labour. Ministry of Commerce, Industry and Labour (MCIL) regulates labour conditions and the contractors will have to comply with Samoan legislation. -

44. Samoa Water Authority. The Samoa Water Authority (SWA) is the national service provider of water supply and more recently for sanitation, sewerage and wastewater treatment5. The SWA also monitor their own water supplies and have a water quality laboratory to support these activities. Because the drinking water is collected in the same river where the powerhouse will be or are installed it requires good coordination between EPC and SWA.

45. Ministry of Agriculture, Forestry and Fisheries. The Ministry of Agriculture, Forestry and Fisheries (MAFF) is responsible for the promotion, and sustainable development and management of irrigation services, and assists MNRE/WRD in the prevention and monitoring of uncontrolled clearance of forests for agriculture in watershed areas. It is related to the project for the conservation of the watershed through the control of the crop field’s development.

46. Ministry of Health. The Ministry of Health (MOH) is responsible for water quality monitoring, inspection and investigation of water safety issues as well as health and safety matters that also fall under the purview of MCIL.

5. There are currently no formal requirements to retain an environmental flow (e-flow) in the watercourses of Samoa. Though this e-flow requirement is required under ADB SPS (2009) requirements for projects in natural habitats.

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47. Other institutions involved are:

• SROS (Research institution) - the Samoa University • Other institutions may be called on for specific analysis if needed during the monitoring phase

2.2 Country safeguard system

48. In summary the Project must comply with the requirements of the Planning and Urban Management Act 2004 and the Environmental Impact Assessment (EIA) Regulations 2007. For development of hydropower projects, development consent must be obtained from the (PUMA) within the Ministry of Works, Transport & Infrastructure and from the MNRE. The development consent application must include an environmental assessment which complies with the Act and Regulation requirements. The relevant regulatory framework for this project is the following:

2.2.1 Lands, Surveys and Environment Act 1989

49. Section 95 of the Act outlines the principal functions of the MNRE which includes advising the Minister on all aspects of environmental management and conservation including: o the potential environmental impact of a public or private development proposal; and o to act as the advocate of environmental conservation at Government, its agencies, and other public authorities with advice on procedures for the assessment and monitoring of environmental impacts.

50. Section 23, of the Act covers the purchase of private land or Government interest in land. Under this section, the Government may, with the approval of the Minister, purchase any freehold land, or the interest of a lessee in any Government land for a Government purpose.

2.2.2 Planning and Urban Management Act 2004

51. The Planning and Urban Management Act 2004 (PUMA) sets out the framework for the planning, use, development, management and protection of land in Samoa. It describes the process where an environmental impact assessment will be required as follows:

52. Section 42: Environmental Impact Assessment –

• The Agency may require an applicant under Section 37 to provide an environmental impact assessment in relation to the proposed development to which the development application relates. • Where the Agency decides that an environmental impact assessment shall be prepared, the format, structure, subject matter of any such assessment and any other related matter, shall be specified in writing by the Agency to the applicant and the applicant shall comply with the Agencies requirements under this section The Act also outlines the process of notification of applications and also the submissions on development applications.

2.2.3 Environmental Impact Assessment Regulations 2007

53. EIA in Samoa is regulated by the Environmental Impact Assessment Regulations 2007 (Regulations). The Planning and Urban Management Agency (PUMA) administer the EIA process, establishing what level of EIA is required, the aspects that need to be included and the process for review and approval.

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54. When an EIA is required under Section 42 of the PUMA Act, it must be prepared and provided in the manner prescribed under these regulations. Section 4 of the regulations prescribes the two forms of EIA:

• A Preliminary Environmental Assessment Report (PEAR) and; • A Comprehensive Environmental Assessment Report (CEAR).

55. A PEAR is required when PUMA considers an activity requiring consent is not likely to have a significant adverse impact on the environment. A CEAR is required when a development is likely to have a significant adverse impact on the environment.

56. Under Section 34 of the PUMA Act, all development needs consent, unless a sustainable management plan or regulations provides otherwise.

57. The Regulations also outline:

• Baseline and compliance monitoring (Section 8); • Reviews of the environmental assessment (Section 9 and 10); and • Public Consultation (Section 11). • Schedules attached to the Regulations detail the content of the PEAR and CEAR.

58. From MFAT Environmental and Social Impacts Guideline (30August 2012 Document ID: 6111649) The following categories reflecting the level of impact or risk and the type of impact assessment required development

Table 2.1: EIA Regulations (2007) Categories of Project

Category Description Assessment required A The Activity has the potential to cause Comprehensive impact assessment covering significant adverse impacts considered the full range of environment and/or social irreversible or unprecedented, and which impacts, and impact management plan extend beyond the physical footprint of the Activity P(A) Same as for ‘A’ but where Activity is being Impact assessment and management implemented by a Partner agency procedures by the Partner will be evaluated and, if required, supplementary work requested to ensure conformity with the requirements of this policy B The Activity has the potential to cause adverse Impact assessment and impact management site-specific impacts, which are potentially plan covering adverse impacts only reversible or more easily mitigated than for category ‘A’. As part of the design phase an impact assessment is to be conducted covering adverse impacts only, along with an impact management plan demonstrating how these will be addressed P(B) Same as for ‘B’ but where Activity is being Impact assessment and management implemented by a Partner agency procedures by the Partner will be evaluated and, if required, supplementary work requested to ensure conformity with the requirements of this policy C Minimal or no adverse impacts None – no further action needed

Source: Environmental and Social Impacts Guideline – MFAT (30 August 2012 - Document ID: 6111649)

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59. Examples of category A

• New airstrips, ports, and related transport infrastructure • Activities taken place within or immediately adjacent to nationally or internationally designated area of conservation or heritage • Large-scale industrial or agricultural Activity • Large-scale land reclamation or coastal development • Large-scale commercial fishing and logging • Large-scale forestation/reforestation, including logging operations • Large-scale aquaculture/marine culture • Use of mangroves or wetlands • Dams or other large-scale water impoundments • Water drainage, abstraction, or irrigation schemes of medium- or large-scale

60. A Comprehensive Environmental Assessment Report (CEAR) shall contain the particulars identified in the Regulations and as agreed with PUMA.

2.2.4 Water Permit and Water Management Act

61. This project will need to apply for a Water permit as it directly deals with waters resources and also have to comply with the Water Management Act related to the protection of watershed.

2.2.5 Forest Act

62. Any project or development that requires to remove trees should apply for a tree-harvesting permit.

2.2.6 Security and Emergency Disaster and Emergency Management Act 2007

63. This act gives guidance of the role, responsibility and actions to be taken after a disaster like typhoons or tsunamis. There is no regulation related to anticipation of these disasters. The Fire and Emergency Service Act 2007 is specifically related to fire. EPC has not prepared an early warning and emergency preparedness Plan. Though it is not internationally required to have a Early Warning and Emergency Preparedness Plan for small hydropower schemes or those without reservoirs, EPC should nevertheless develop such a Plan in the future mainly to be prepared to face extreme situations.

64. Obtaining permit for new HPP 89. To build new hydro-power schemes two consents should be obtained by: (i) an application for a water permit should be lodge to the WRD of the MNRE and (ii) an application delivered by PUMA (MNRE).

65. When a project belongs to the competency of several authorities and could have potentially significant environmental effects, the section 44 of the PUMA Act 2004 states that PUMA will consult appropriate authorities by sending a referral to the relevant Authorities requesting comments. The answer of the authorities will be made within 10 days, unless they need more information.

66. The timeframe to obtain a permit for a project depends on its complexity and the number of Agencies involved.

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2.2.7 Protection of Wildlife Regulations 2004

67. These regulations deal solely with the protection of flying endemic species. Under these regulations no person is allowed to harm flying species endemic to Samoa unless approval is granted by the Minister of Natural Resource and Environment. Flying endemic species are defined as any of the following:

• Flying fox; • Pigeon; • Crimson crown fruit dove; • Wattle honeyeater; and • Cardinal honeyeater.

68. “Harm” is defined as trapping, shooting, killing or otherwise destroying.

2.3 Policies for Samoa

2.3.1 Cultural and Natural Heritage Conservation Policy 2004

69. This policy provides the framework for the conservation, preservation, use, allocation and sustainable management of heritage resources. It also seeks to improve approaches to heritage planning by ensuring that the preservation of natural and cultural heritage are fully recognized and taken into account in the formulation and implementation of development programs.

2.3.2 Planning for Climate Change Policy

70. This policy addresses national responses to Climate Change as identified in the National Environment Management Strategy (NEMS) 1993. The local risks from greenhouse warming are defined as: coastal inundation; shoreline retreat; more severe and frequent storms and wave condition; enhance coastal sedimentation and threat to infrastructure and services.

2.3.3 Policy Statement on Biological Diversity

71. This policy statement provides the framework for the conservation, sustainable use and management of Samoa's terrestrial and marine biodiversity including the protection of endemic and native species and the control of invasive species.

2.3.4 Samoa Codes of Environmental Practice 2006

72. The Samoa Codes of Environmental Practice (COEP) have been prepared (2006) to define methods and/or procedures to be followed by consultants, designers and contractors. They seek to avoid or mitigate adverse environmental effects that may arise out of infrastructure development projects or maintenance work. The COEP is to be implemented for the planning, design and construction of all development works where development consent is required under PUMA.

73. Though these Codes refer essentially to road construction, guidance on public consultation, land acquisition and slope and soil protection, campsites, archaeological discovery, drainage, Earthworks Plan, Erosion and Sedimentation Measures, etc.

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74. There are three implementation mechanisms for the COEP: (i) use of the COEP is specified in the Terms of Reference for the design of works. The relevant design directives stated in the COEP should also be incorporated in the Terms of Reference; (ii) use of the COEP is specified in the specifications for the construction of physical works. The relevant suggested specifications stated in the COEP should also be incorporated in the specifications; and (iii) environmental approvals are granted with the condition that works proceed under the provisions of the COEP.

75. There are 14 COEP which were prepared under the PUMA which include:

• COEP 1 – Administrative Procedures; • COEP 2 – Road Planning, Design and Construction; • COEP 3 – Consultation; • COEP 4 – Land Acquisition and Compensation; • COEP 5 – Construction Camps; • COEP 6 – Road Construction Erosion Control; • COEP 7 – Slope Stability; • COEP 8 – Quarry Development and Operations; • COEP 9 – Gravel Extraction; • COEP 10 – Coastal Protection; • COEP 11 – Drainage; • COEP 12 – Traffic Control During Construction; • COEP 13 – Earthworks; and • COEP 14 – Cellular Telecommunications Facilities.

76. Of these, COEP 2, 3, 4, 6, 7, 9,11, 12 and 13 are relevant to the project.

2.3.5 Statement of Economic Strategy (SES) 2000 – 2001

77. Samoa’s Economic Strategy seeks to encourage private sector led, and broader based growth in outputs and employment, as well as facilitating social development. The education and health sectors are a high priority in order to provide people with greater opportunities to advance themselves. Significant support is also given to rural development programmes to improve power distribution, transport infrastructure, and communications to create more opportunities for those in Savai’i and the rural areas of Upolu, where lowest income levels tend to occur.

2.3.6 Strategy for the Development of Samoa 2017 - 2020

78. The Vision of the 2017-2020 Strategy for the Development of Samoa is for ‘Accelerating Sustainable Development and Broadening Opportunities for All’. The Strategy for the Development of Samoa identifies the four priority areas of development (Economic, Social, Infrastructure and Environment) and 14 key outcomes to be achieved for Samoa over the next four fiscal years. The SDS is aligned with the Sustainable Development Goals and the Small Island Developing States (SIDS) Accelerated Modality of Action (SAMOA) Pathway.

79. Outcomes relevant to this Project are included in:

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80. Key Outcome 12 – Quality Energy Supply (Vision - sustainable energy supply - towards energy self-sufficiency). Renewable energy developments are the main focus in the energy sector for the next four years. A number of large projects will be implemented to ensure the future supply of electricity and will provide for the expected growth in demand. Solar energy plants such as the Tuanaimato and Vaitele and Salelologa sites, together with the largest solar panel project farms at Faleolo will be extended. Rehabilitation of the Loto Samasoni and Fale ole Fee hydro power plants together with new hydro plants for Tafitoalo/Fausaga and Faleata will contribute to the Renewable Energy outcome. An increased number of renewable energy projects will be implemented through partnerships between the private sectors, government and communities.

81. Key Outcome 13 – Environmental Resilience Improved (Vision - improved environmental sustainability and disaster resilience). Samoa’s natural and environmental resources will be better protected, managed and developed in a sustainable manner with improved resilience to natural and human- induced hazards, disaster and climate impacts and will better support a sustainable and healthy human population. Targeted interventions will be made in Key Biodiversity Areas with improved planning, management and acquired legal status. The state and trend in condition of environmental and natural assets such as lands, forest, freshwater (surface and groundwater) native (including endemics) species diversify (terrestrial and marine), fisheries (inshore and offshore), oceans and air quality will be improved and monitored closely.

82. Rehabilitation and/or restoration of degraded ecological areas from ridge to reef covering upper watershed and forest areas will be improved by replanting native and fruit bearing trees; downstream coastal and mangrove areas including coral relating and eradication of invasive species will be promoted and implemented with targeted communities.

83. Key Outcome 14 – Climate and Disaster Resilience (Vision - a climate and disaster resilient Samoa with planning, risk reduction, response and recovery improved with increased coordination amongst stakeholders). Climate and disaster resilience planning and implementation actions will be integrated into all sector plans and Implementing Agency corporate plans ensuring adoption of Samoa’s climate and disaster policies. Climate and disaster resilience plans and works will be coordinated in a way that ensures all funded projects achieve maximum effect. The submission of Samoa’s Flood Mitigation Plan to the Green Climate Fund illustrates how Samoa is able to better access global funds being made available under the Paris Agreement.

84. Climate and disaster resilience policies will be maintained in Samoa that detail disaster risk management arrangements to ensure the mitigation of, preparedness for, response to and recovery from the impact of disasters.

2.3.7 Energy Sector Plan 2012 - 2016

85. The key guiding document for all energy projects in Samoa is the Energy Sector Plan, published by the Samoa Ministry of Finance in December 2012. This plan supersedes the National Energy Policy (2007) and the Strategic Action Plan (2008). Samoa has a “Carbon Neutral by 2020” goal approved by Cabinet in 2010, with the Energy Sector Plan as the guiding document for this goal.

86. As part of the PEDAP a 100% Renewable Energy Roadmap for Samoa is being developed by separately.

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2.4 Relevant International Agreements

87. According to the Samoan Ministry of Foreign Affairs and Trade, Samoa is a party to the following Environment Conventions and Treaties.6

• Agreement establishing the South Pacific Regional Environment Program (SPREP), 1993; • Convention for the Protection of the Natural Resources and Environment of the South Pacific Region, 1986; • Protocol for the Prevention of Pollution of the South Pacific Region by Dumping, 1990; • Convention on the Conservation of Nature in the South Pacific, 1976; • United Nations Framework Convention on Climate Change, 1992; • Kyoto Protocol to the Framework Convention on Climate Change, 2005; • Convention on Biological Diversity, 1992; • Vienna Convention for the Protection of the Ozone Layer, 1985; • Montreal Protocol on Substances that Deplete the Ozone Layer, 1987; • United Nations Convention to Combat Desertification, 1994; • Convention concerning the Protection of the World Cultural and Natural Heritage, 1972; • Convention on the Prior Informed Consent Procedure for Certain Hazardous Chemicals and Pesticides in International Trade, 1998; • Basel Convention on the Control of Trans-boundary Movements of Hazardous Wastes and their Disposal, 1989; • Convention on Persistent Organic Pollutants, 2001; • Convention on Wetlands of International Importance, 1971; • Convention on International Trade in Endangered Species of Wild Fauna, 1973; • Convention of Migratory Species of wild animals, 1979; • Protocol concerning Cooperation in combating Pollution Emergencies in the South Pacific Region, 1990; • Carthagena Protocol on Biosafety to the convention of Biological Diversity, 2003; • International Plant Protection, 1951; • International Treaty on Plant and Genetic Resources for Food and Agriculture, 2001; • Plant Protection Agreement for the South East Asia & Pacific Region, 1956; • Strategic Approach to International Chemicals Management, 2007.

6 https://www.mfat.gov.ws/political-international-relations-protocol/conventions-treaties/

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2.5 Relevance of Legal, Policy, and Administrative Frameworks

88. The Samoan policies and frameworks assessed above support the development of new small Hydro Power Plants. This includes the Strategy for the Development of Samoa, which seeks to improve the overall quality of life for Samoan. Key, policy or administrative frameworks that support the project are:

89. Statement of Economic Strategy (SES) which supports development program to improve power distribution, transport infrastructure, and communications, in order to create more opportunities for those in Savai’i and the rural areas of Upolu, where lowest income levels tend to occur.

90. Energy Sector Plan. This is the key guiding document for all energy projects in Samoa. Samoa has a “Carbon Neutral by 2020” goal approved by Cabinet in 2010, with the Energy Sector Plan as the guiding document for this goal.

2.6 Safeguard Policy Statement

2.6.1 Environmental Requirements

91. This EIA has been prepared following the guidance contained in the ADB’s Safeguard Policy Statement 2009 (SPS).7 ADB uses a classification system to reflect the significance of a project’s potential environmental impacts. The Project should:

• Avoid adverse impacts of projects on the environment and affected people; • Where possible; minimize, mitigate, and/or compensate for adverse project impacts on the environment and affected people when avoidance is not possible; and • Help borrowers/clients to strengthen their safeguard systems and develop the capacity to manage environmental and social risks.

92. Projects are screened according to type, location, scale, and sensitivity and the magnitude of their potential environmental impacts, including direct, indirect, induced, and cumulative impacts. The SPS categorizes potential projects or activities into categories of impact (A, B or C) to determine the level of environmental assessment required to address the potential impacts.

93. Projects are assigned to one of the following four categories:

• Category A: A proposed project is classified as Category A if it is likely to have significant adverse environmental impacts that are irreversible, diverse, or unprecedented. These impacts may affect an area larger than the sites or facilities subject to physical works. An Environmental Impact Assessment is required. • Category B: A proposed project is classified as Category B if its potential adverse environmental impacts are less adverse than those of Category A projects. These impacts are site-specific, few if any of them are irreversible, and in most cases mitigation measures can be designed more readily than for category A projects. An Initial Environmental Examination is required. • Category C: A proposed project is classified as category C if it is likely to have minimal or no adverse environmental impacts. No environmental assessment is required although environmental implications need to be reviewed.

7 https://www.adb.org/documents/safeguard-policy-statement

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• Category FI: A proposed project is classified as category FI if it involves investment of ADB funds to or through a financial intermediary.

94. A project’s category is determined by the category of its most environmentally sensitive component, including direct, indirect, cumulative, and induced impacts in the project’s area of influence. The Alaoa Multi- Purpose Dam Project has been screened and categorized as A for environment. It has been determined that an EIA prepared under the provisions of the ADB’s safeguard policy would fully satisfy all the requirements for a CEAR under the PUMA Environmental Impact Assessment Regulations 2007.

95. In terms of social safeguards, encroachment on the 1921 Ordinance land is a modest issue today, however, and presents a modest involuntary resettlement issue for the project in the form of economic displacement of 17 planters and their families (total approximately 144 adults and children). As a result, the project is designated Category B for involuntary land acquisition and resettlement (no involuntary land acquisition but some involuntary economic displacement). A resettlement plan has been prepared.

96. The SPS applies pollution prevention and control technologies and practices consistent with international best practices as reflected in internationally recognized standards such as the World Bank Group’s Environmental, Health and Safety Guidelines (EHSG). The EHSG provide the context of international best practice and contribute to establishing targets for environmental performance. The air and noise standards in the EHSG will be used in parallel with local standards (where they exist) throughout this document.

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3 Description of the Project

3.1 Project components

97. The catchment includes four catchments of Western, Middle, Middle Eastern and Eastern (Figure 3.1) The objective for the dam is to provide flood protection. The larger the dam catchment (i.e. the influence of the storm rainfall event that can be regulated) the greater the impact / improvement the dam will have on the flood reduction downstream.

Figure 3.1: The four sub catchments in the Vaisigano catchment

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98. The project was tasked with confirming the practicality and viability of constructing a multipurpose dam on the Eastern Branch of the Vaisigano River (the eastern and middle eastern branches) to provide: (i) flood protection for downstream assets and Apia; (ii) guarantee water supply; and (iii) provide hydropower generation.

99. While this EIA is focused on the environmental implications of the preferred engineering option, where appropriate it looks at the wider implications of development in the basin to confirm that environmental requirements are met. With its restricted brief of only looking at a dam in the Middle Eastern / Eastern Branch, the engineering feasibility study was confined to the investigation of two dam site locations specifically: (i) the Vaisigano Middle Eastern Branch, 430m upstream of the confluence of the Vaisigano Eastern Branch and the Vaisigano Middle Eastern Branch (Posch, 2013); and (ii) the combined branch of the Middle-Eastern and Eastern Branches of the Vaisigano catchment) upstream of the Alaoa Power Station, but downstream of the confluence between the Vaisigano Middle Eastern Branch and the Vaisigano Eastern Branch.

100. Only the second of these dam sites (combined Eastern Branch upstream of the Alaoa Power Station) met the required dam objectives. Therefore, the recommended dam site is on the combined Vaisigano Eastern Branch upstream of the Alaoa Power Station, but downstream of the confluence between the Vaisigano Middle Eastern Branch and the Vaisigano Eastern Branch. As part of a separate project a flood protection wall is being constructed on the lower reach of the Vaisigano River, this will provide flood protection up to the 1 in 20-year flood. Following the completion of the flood retention dam, the existing hydropower infrastructure on the Vaisigano River and Alaoa water treatment plant will be protected to the 1 in 200-year flood event (Figure 3.2).8

Figure 3.2: Location of flood protection walls in Apia – in relation to project

8 Entura. 2018. Feasibility Study - Section 16.2 Para 4.

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101. Following detailed engineering studies including geotechnical and hydrological investigations, different storage options, different types of dam construction and financial and economic considerations a preferred option was selected. The preferred general arrangement for the Project is presented in Figure 3.2, with a summary of the projects features in Table 3.1. The key features include: the height of the dam above the foundation is 59.6m the width of the dam at the crest (top) is 320m and it is constructed using the Roller Compacted Concrete (RCC) technique. RCC is a mix of cement/fly ash, water, sand, coarse aggregate with less water than conventional concrete. The material is delivered by dump trucks or conveyors, spread by bulldozers and then compacted by vibratory rollers.9

Table 3.1: Key characteristics of the project

Component feature Dimension/rate Dam Type Roller Compacted Concrete Height above foundation 59.6m Dam Crest Level RL 179.6 Crest Length of Dam 320m Operating Levels Normal full supply level (NFSL) RL 152.4 m Normal minimum operating level (NMOL) RL 152.3 m Normal tail water level RL 116.0 m Spillway Type Un-gated Ogee Crest Chute Spillway Spillway Crest Level RL 174.6 m Spillway Crest Length of Dam 62.0 m Penstock Pipe Type Surface and buried Penstock Diameter 0.9m, circular shaped Length 398m Velocity through Penstock 2.1m/sec Powerhouse Type Surface Gross Head 36.4m Rated Head 34.87m Tail race channel Type Reinforced concrete channel Power generation Optimum Installed capacity 0.40 MW Annual average energy 2.12 GWh

9 https://en.wikipedia.org/wiki/Roller-compacted_concrete

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Figure 3.3: General arrangements and layout of the preferred dam option

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3.2 Proposed project delivery mechanism

102. The Alaoa Dam is a multi-purpose dam and therefore has multipurpose objectives. Its multi-purpose objectives are: (i) flood protection; (ii) seasonal water supply; and (iii) hydropower generation.

103. Flood protection will be provided by the dam by providing free space in the reservoir to store and retain floods. The greater the flood retention volume allowed for in the overall storage the greater the resulting flood protection. The flood retention will provide flood protection for existing downstream hydropower and water supply assets.

104. The second objective of the dam is to provide seasonal water supply storage to guarantee the Apia water supply during low flow years.

105. The third objective is to look at utilising the storage for power generation. The additional power generation will be from two sources:

• From a new station associated with the Alaoa Dam project; and • From additional flow regulation for the Samasoni small hydro station due to the new dam.

106. Figure 3.4 indicates how water will be stored behind the dam to meet the project objectives.

Figure 3.4: How water will be stored behind dam for flood protection, water supply and power

107. Schedule and timeframe. The time to construct the project will be just over three years.

108. Project cost. The total project cost was calculated to be US$68.08 Million. This is excluding taxes, cost of interest during construction and financing charges.

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4 Alternatives

4.1 Overview

109. The project has multi-purpose objectives of providing flood protection; seasonal water supply; and hydropower generation In considering alternatives the following are discussed:

• Technological - Is there an alternative to a dam / impoundment? • Other locations - Are other sites available? • Construction alternatives – different types of dam / impoundment • Ecological Considerations • No project

4.2 Technological - Alternative to a dam

110. The scope of the technical feasibility study was limited to the feasibility of developing a multipurpose dam with a primary objective of food protection and secondary objectives of protecting seasonal water supply and hydropower generation. Due to the topography associated with the catchment a major storm event results in a rapid, potentially catastrophic, concentration of floodwater that will be funnelled through populated areas of Apia. While the UNDP project that is providing flood protection through channelisation of the Vaisigano river in its downstream section, the upper sections are unprotected and important infrastructure (water treatment works, hydropower plants) are unprotected. A dam to hold back flow is the only reliable option to protect the downstream areas adjacent to the Vaisigano River.

4.3 Location and site alternatives

111. Two dam sites have been nominated in the Terms of Reference: (i) an upstream dam on the Vaisigano Middle Eastern Branch, 430m upstream of the confluence of the Vaisigano Eastern Branch and the Vaisigano Middle Eastern Branch; and (ii) a downstream dam on the combined Vaisigano Eastern Branch upstream of the Alaoa Power Station, downstream of the confluence between the Vaisigano Middle Eastern Branch and the Vaisigano Eastern Branch. These two locations are shown in Figure 4.1.

4.3.1 Different dam types and sizes

112. There have been two main studies (2013 and 2016) for dams in the Vaisigano River catchment though not for a multi-purpose dam. These studies are briefly summarized below.

113. Options study 1 – 2013. This was an ADB Technical Assistance project TA-8308 SAM: Renewable Energy Project – Small Power Plant Scheme and Rehabilitation Plan (Posch & Partners) and looked at a range of small hydro projects around Samoa, including a storage project in the Vaisigano catchment. This report proposed a dam on the Vaisigano Middle Eastern Branch, 430m upstream of the confluence of the Vaisigano Eastern Branch and the Vaisigano Middle Eastern Branch. This dam was predominantly sized for energy production but recognised that there would be other benefits such as increased reliability of water supply and a reduction in the flood flows for the downstream region of Apia. The proposed dam was 85m high providing a reservoir volume of around 4 million m3. The most promising dam types were considered to be a rockfill dam (either central earth and rockfill, or concrete faced rockfill) or a roller compacted concrete dam. Site visits were undertaken as part of this study.

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Figure 4.1: The two dam site options considered

Source: AMPD Project Terms of Reference

114. The main issue with this dam is that the location would not provide significant flood reduction, as this dam would only regulate approximately 20% of the overall Vaisigano catchment. Given that the highest priority is flood protection, this is not the ideal location for a storage dam. A dam site further downstream regulating more of the catchment area would be a better solution.

115. Options study 2 – 2016. This report details a desktop study of flood storage options within the Vaisigano catchment above Apia, Samoa. This desktop study utilised Lidar survey available for Samoa. The objective of the study was to identify potential locations for the attenuation of a 1 in 100-year flood whilst allowing a 1 in 20-year flood downstream, which can be contained within the flood defence works currently under construction within Apia. Therefore, the dams considered in this report were single purpose dams, i.e. flood protection. These dams do not have water in them during normal flow conditions and they will only come into operation during major floods.

116. Two options were proposed to meet this flood protection criterion, a single dam option and a two- dam option. Neither of these options provided water supply or power generation benefits.

117. The single dam option was located at the Samasoni weir site. A 5 Mm3 storage was proposed at this site, with the dam crest level at RL 133m, approximately a 39m high dam with a crest length of 220m. No allowance was made for dead storage in this calculation. The main issue with this dam is that it floods both Samoa Water Supply’s Water Treatment Assets at Alaoa and EPC’s Alaoa and Fale ole Fee power stations, and therefore does not have the support of EPC and Samoa Water Authority.

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118. The two dam option consisted of a dam on the East branch just above the Alaoa Power Station (as per the current proposed dam site) and a second dam on the western branch, just upstream of the confluence between the east and west branches of the Vaisigano River. The dam on the east branch had a reservoir volume of 2.8 Mm3, with a corresponding dam height of around 43m. The dam on the west branch had a reservoir volume of 1.7 Mm3, with a corresponding dam height of around 45m. Again, no dead storage was allowed for.

119. Five dam types were considered in this report: zoned embankment dam; concrete faced rockfill dam; concrete gravity dam; the RCC type; and faced symmetrical hardfill dam. The concrete gravity dam was eliminated based on the high quantity of cement required. The zoned embankment dam was not considered appropriate due to the minimal earth-fill material available near the site. Based on a high-level assessment by MWH this report concluded that the best dam option for these sites was a faced symmetrical hardfill dam. Although other dam options may still be viable or cost effective, this preliminary assessment adopted this type for cost estimations for these dams.

120. During the current feasibility study work, the Entura assessment and report concluded that a RCC type dam is the best dam type for this dam site.

4.3.2 Hydropower options

121. A total of nine hydropower options were considered, based on three locations for the new power station and 3 different storage scenarios for the hydropower arrangement, giving a 3 x 3 matrix. There are three logical options for the location of a new hydro plant associated with the dam:

• Option PS-1: In this option the power plant has been envisaged at toe of the proposed dam. This ultimately became the preferred option following ecological assessments.

• Option PS-2: The power plant is located upstream of the Water Supply Off-take downstream of Alaoa power plant. The initially preferred option as it maximises efficiency of the hydropower plant.

• Option PS-3: The power plant is located Just upstream of the Samasoni head pond and the tail water can directly feed the Samasoni head pond.

4.3.3 Storage options

122. Three hydropower storage options considered included: (i) large (or significant) storage - a total of 2.6 Mm3 was provided to enable a reasonable amount of flow regulation; (ii) medium storage - a total of 0.7 Mm3 was provided to enable smoothing of flow across a number of days; and (iii) run-of-river (or no storage): The minimum possible storage was provided to enable the storage model to still operate; this was equal to 6,640 m3 (or 0.1m of storage in the reservoir). The run-of-river option could also be used for daily peaking by utilising some of the flood storage just for the day.

123. Based on these nine options, a financial analysis was undertaken to determine the LCOE. The cost attributed to the hydropower portion of the project was only considered in this analysis. The minimum LCOE was for the run-of-river options, which were significantly less than any of the hydropower storage options. Therefore, it was concluded that hydropower storage cannot be justified i.e. the hydropower element will effectively be “run of river”.

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4.4 Ecological considerations

4.4.1 Environmental Flow

124. The development of any dam will result in habitat loss due, as a minimum, to the inundation of an area behind the dam. In addition. the operation of a dam will prevent flows travelling downstream, changing the characteristics of watercourses (streams and rivers) previously fed by the catchment. This may adversely impact on humans and flora and fauna that previously relied on the watercourse.

125. Four project specific technical studies were carried out that included the assessment of implications on humans and flora and fauna due to the dam impoundment, they are: (i) Terrestrial biodiversity and habitat assessment; (ii) Assessment of Environmental Effects – Birds and Bats; (iii) Environmental Flow Assessment; and (iv) Natural and Critical Habitat Assessment.

126. The Environmental Flow Assessment (Annex D) noted that “Existing regulation (for hydropower ed.) has significantly reduced the flow regime in the five kilometres of the east branch downstream the offtake for the Fale ole Fee Power Scheme; the 1.3 kilometre reach of the middle branch downstream from the offtake for the Alaoa Scheme; and, the 4.2 kilometre reach of the main branch downstream from Samasoni Weir to the tailrace for Samasoni Power Scheme. These reaches experience zero flow for extended periods each year, provide no aquatic habitat and reduce the pathways for migratory species to move up and downstream. Aquatic surveys indicate that migration of aquatic species upstream into the east and middle branches and downstream to the sea is being significantly reduced by this flow regulation compared to the middle-east and west branches which have permanent flow. Extended periods of zero flow downstream of Samasoni Weir on the main branch would also reduce the upstream and downstream migration from all four branches of the river which start upstream of this weir”.

127. The initial technical proposal for the project was to site the new hydropower station 350m downstream from the base of the dam and maintain an environmental flow from immediately below the point where the existing hydropower station joins Vaisigano River (250m downstream from the dam base) supplemented with flow from the new hydropower plan (350m downstream from the proposed dam base) and improve regulation at the Samasoni Weir i.e. maintain almost year round flow form the upstream hydropower plants to the sea but leaving the 250m above the first hydropower plant up to the dam without a maintained flow.

128. The Natural and Critical Habitat Assessment concluded that “Downstream rivers have been degraded by cumulative impacts from existing weirs, but upstream rivers remain mostly Natural Habitat”. In this regard it was important to maintain, or enhance the riverine habit to ensure no-nett loss of river function as required by the SPS for projects located in natural habitats and to this end it was concluded that a flow in the Vaisigano River was needed from immediately downstream of the proposed dam-site. Therefore, for environmental considerations, the project hydropower station should be located immediately downstream from the dam site, and not 350m downstream as was originally proposed. This is now the preferred project arrangement.

4.4.2 Species migration past Samasoni Weir

129. A low dam currently diverts all flow into a holding reservoir for the Samasoni Power station (downstream). EPC can maintain an environmental flow past the dam by opening a penstock valve on the right bank of the Vaisigano river. However, the concentrated flow through this penstock valve will not allow for species migration and it would be preferable to provide a “fish ladder / fish pass” to maintain a migratory path past the Samasoni weir. The fish ladder / fish pass would also remove the need for the regular opening of the penstock valve. The following plates show the high flow through the existing penstock valve, during periodic flushing, and an installed fish ladder in operation.

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Plate 4.1: Penstock valve open at Samasoni Dam (November 2019)

Plate 4.2: Lopwell Dam Fish Ladder, Plymouth, Devon, United Kingdom

4.5 No project

130. With no project in place the catastrophic flooding threat will not be removed. With climate change predicted to increase the severity and frequency of extreme rainfall events the likelihood of damage to vital infrastructure (water treatment plant and hydropower generation) and loss of life and property will be worsened. Therefore, a no project option is not considered to be an acceptable option.

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5 Description of Existing Environment (Baseline)

131. This section borrows from the National Environmental Sector Plan (NESP 2017 – 2012 prepared by the MNRE and project specific reports prepared in 2018 and 2019 and included as Volume 2 of the EIA (summarized in Appendix 2).

5.1 Physical Environment

5.1.1 Geography and topography

132. The topography of Samoa is rugged and mountainous with about 40 per cent of Upolu and 50 per cent of Savai’i characterized by steep slopes descending from volcanic ridges. The interior of both main islands is still covered with mountain forests and, in the case of the highest peaks on Savai’i, covered in cloud forest. These areas also contain volcanic peaks with the Upolu crestal ridge rising to 1,100m. Savai’i has more and younger volcanic cones with the highest peak reaching 1,848m at Mt. Silisili. Western Savaii and northwest Upolu are almost devoid of surface streams, corresponding to the rain shadow and sub- surface drainage. The topography of the Vaisigano watershed and catchment area is shown in Figure 5.1.

Figure 5.1: Vaisigano catchment topography and project area

Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

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133. The slopes in the valleys of the Vaisigano River catchment are very steep, as shown in Table 5.1. The steep valley sides and steep stream gradients of the Vaisigano catchment make the downstream vulnerable to rapid-rising flood water following heavy rain as well as potentially high sedimentation loads.

Table 5.1: Slopes in the Vaisigano watershed

Slope class Area (ha) Proportion 0-15% (shallow slope) 735 22% 15-30% 549 15% 30-100% 519 17% >100% (steepest slope) 1,497 46% 3,300 100%

Source: Baisyet et al (1990, p.10)

5.1.2 Geology and Soils

134. The geology of Samoa was described by Kear and Wood (1959), Kear (1967) and Keating (1992). A geological map of Upolu produced by New Zealand Geological Survey (1958) in association with the paper of Kear and Wood (1959) (Figure 5.). The majority of the Vaisigano River catchment is Salani Volcanics (S) (Late Pleistocene, around 1 Ma). The lithology of Salani Volcanics is critic basalt and olivine chlorite and basalts that typically grade upward from porphyritic basalt through vesicular basalt to rubbly a’a (Richmond, 1992; Keating, 1992). The Salani Volcanics overly the older (1.5 – 2.8 Ma) Fagaloa Volcanics (F). Most of the drainage system flows through Salani Volcanics, but the geological map indicates the presence of a strip of Pu'apu'a Volcanics (P) on the Eastern Branch river channel from downstream of the dam site to 'O le Fale o le Fe'e. This later young volcanic formation (around 300 BP) consists of lava flows and very little weathering. Fukuyama Shoji Company Limited (2013) reported that this material was very hard to drill.

135. Most of the coastal area around Apia area is underlain by material of Holocene age. The lowland floodplain of the Vaisigano River is Alluvial swamp, and the Holocene unit closer to the coast is known as Tafagamanu Sand, described by Kear and Wood (1959) and Richmond (1992) as a raised beach deposit of coral sand with some coral and basalt gravel. Richmond (1992) classified the coastline east of Apia as Type III, described as fringing reefs and narrow coastal strip or beaches, barrier spits, coastal swamps associated with streams. West of Apia the coastline was Type I, described as wide fringing reef transitional to shallow barrier reef.

136. Additional description of the soils of Upolu was provided by Keating (1992). Early studies by Hamilton and Grange (1938) and Seelye et al. (1938) showed that soils were relatively shallow, heterogeneous, with frequent stones and boulders. On Salani Volcanics, the surfaces of lava flows are often deeply weathered, with soil often more than 100 mm thick. On the distal flows (i.e. distant from the source crater), over 300 mm of soil has formed (Keating, 1992, p. 143).

137. Kersch et al. (2013) undertook a geological site investigation along the bed and slopes of the Vaisigano River in the area proposed for the Alaoa Dam. The survey began at the intake to the eastern canal and extended to the dam site. It was found that much of the valley slopes in the catchment were unstable, evidenced by landslips. The tuffs and other loose volcanic material had weathered to loamy materials that were easily eroded from hillslopes and undercutting of weaker material underlying resistant basalts resulted in rock fall.

138. The soils of Upolu were mapped and described by the Provisional Soil Map of Upolu, Western Samoa (New Zealand Soil Bureau, 1956) (Figure 5.2).

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Figure 5.2: Extract of the geological map of Upolu

Source: New Zealand Geological Survey/Kear and Wood (1959) in Volume 2 – Annex E Geomorphic Impact Assessment

139. The majority of the headwaters and mid-catchment areas of the Vaisigano River catchment are in steep Latosolic (tropical) soils from basalt, andesite and basic volcanic ash. In the area of the proposed Alaoa Dam reservoir, soils are very steep Latosolic soils from basalt, andesite and basic volcanic ash or calcareous basic tuff, and clay hill soils. The strip of Pu'apu'a Volcanics (P) on the Eastern Branch river channel is associated with Recent soils from basaltic alluvium, clay.

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Figure 5.3: Digitised version of Provisional Soil Map of Upolu – catchment and dam site

Source: Digitized for current study from base prepared by New Zealand Soil Bureau (1956) in Volume 2 – Annex E Geomorphic Impact Assessment

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5.1.3 Climate

140. Samoa has an equatorial/monsoonal climate with all months above 18°C, and an average annual temperature of 26.5°C. The wet season is from October/November to April/May. Typhoons can sometimes occur over the period December to March/April. Trade winds temper the climate in the dry season between April/May and October/November. Samoa’s mountains have a significant effect on rainfall distribution. Wetter areas are located in the south-east and relatively sheltered, drier areas in the north-west. Samoa’s climate varies considerably from year to year due to the El Niño- Southern Oscillation (Elvey and Gippel, 2019). On average, June can be the coolest month with low of 21oC and high of 27oC, May and Jul-Oct usually have low of 23oC and high of 28oC. The warmest months are Nov-Apr with low of 24oC and high of 29oC.

141. Rainfall. The available rainfall data for Upolu was reviewed and summarised by Entura (2018). Relatively long records of daily observed rainfall were available for Apia and Alaoa stations, while Tiavi and Mt Le Pue stations had short patchy records. For Afiamalu station a mean monthly rainfall distribution was available. In addition, a simulated hourly rainfall time series was available (www.meteoblue.com) for Lanafala. These stations were located across arrange of locations and elevations within or nearby to the Vaisigano River catchment. Rainfall increased markedly with elevation (Figure 5.4), with mean annual totals for Apia (2 m), Alaoa (260 m) and Afiamalu (798 m) stations being 2,993 mm, 4,020 mm and 4,849 mm respectively. The simulated rainfall from Lanafala were lower than all other stations, even though located mid-catchment, suggesting the simulation systematically underestimated rainfall. From 2007 onwards, Alaoa rainfall data indicated a positive step change that was not present in Lanafala or Apia data (

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142. Figure 5.5). The small amount of data from Tiavi and Mt Le Pue suggested that they had similar rainfall, and high rainfall compared to other lower-elevation stations (Figure 5.5).

Figure 5.4: Mean monthly rainfall – 3 stations within or near Vaisigano River catchment

Note. The stations Apia (2 m), Alaoa (260 m) and Afiamalu (798 m) are located at increasing elevations.

Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

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Figure 5.5: Annual rainfall distributions - 5 stations within or near Vaisigano River catchment

Note. Tiavi, Mt Le Pue have only two complete years of data. Lanafala data (from 1985) simulated, not observed.

Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

143. Wind. Statistics describing the simulated wind data from Lanafala (Figure 5.6 and Figure 5.7) were comparable to those of Holden (1991). For example, in the simulated data, winds from the east, southeast and northeast comprised 78.5% of the total winds, and the average wind speeds from these three directions was 24.2 km/h. Winds at Lanafala of less than 5 km/h prevailed 3% of the time while winds between 5 and 23 km/h prevailed 50% of the time. Winds above 49 km/h occurred less than 0.2% of the time.

Figure 5.6: Distribution of wind speed by month (top) and by direction (bottom) for Lanafala

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Figure 5.7: Distribution of wind speed by direction for Lanafala

Location: (13.9°S 171.75°W 421 m asl). Based on hourly weather model simulations 1985 – 2019 Source. Data provided by meteoblue (www.meteoblue.com)

5.1.4 Climate Change

144. Climate change has been recognised as a risk to Samoa in terms of impact on floods and yields. The main drivers for Samoa’s rainfall are the South Pacific Convergence Zone and the El Niño Southern Oscillation (ENSO). Samoa’s rainfall is greatly influenced by the position and strength of the South Pacific Convergence Zone. This band of heavy rainfall is caused by air rising over warm water where winds converge, resulting in thunderstorm activity. It extends across the South Pacific Ocean from the Solomon Islands to the Cook Islands and lies between Samoa and Fiji during the wet season.

145. Samoa’s mountains have a significant effect on rainfall distribution. Wetter areas are located in the south-east and relatively sheltered, drier areas in the north-west. There is considerable interannual variability in rainfall over Samoa, that is strongly correlated with El Niño and La Nina events. Severe flooding in Samoa is generally associated with cyclones, however heavy rainfalls can also result in flood events.

146. Samoa, in particular the urban areas of Apia, suffers greatly from the effects of flooding. The last major flood, in 2012, caused direct losses of SAT 251.6 million. Other reported major floods have occurred in 1939, 1974, 1975, 1982, 1990, 1991, 2001, 2003, 2006, and 2008. (D. Lumbroso et al, 2006). The Vaisigano catchment has a high proportion of very steep slopes which are also susceptible to effects of climate change – increase rainfall, increased extreme events.

147. The most important driver of global climate as well as Pacific wave climate is the El Nino Southern Oscillation (ENSO), whose ocean-atmosphere mechanisms play out in the equatorial Pacific. ENSO oscillates with a period of 2-7 years between El Nino, which brings lower than normal sea levels, weaker trade winds, cooler ocean temperatures and higher barometric pressures across the western equatorial Pacific, and La Nina, which brings the opposite conditions (Figure 5.8). Predominant trade winds and easterlies are shown with yellow arrows, Convergence zones with rainfall are shown in blue. The warm pool of near surface water that oscillates in depth and extent across the equator during ENSO is shown in red along with high pressure systems indicated with ‘H’.

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Figure 5.8: El Nino southern oscillation

Source: PACCSAP (2014)

148. The climate change projections for Samoa, based on the low, medium and high emissions scenarios have been calculated by the Pacific Climate Change Program Partners.10 All emissions scenarios indicate the rise of annual average air and sea temperature. The projections are presented in Table 5.2.

Table 5.2: Projected change in temperature under different emission scenarios

Projection year Emissions scenario 2030 °C 2055 °C 2090 °C Low 0.2-1.0 0.6-1.4 0.8-2.0 Medium 0.4-1.2 0.9-1.9 1.5-2.9 High 0.4-1.0 1.0-1.8 1.9-3.3

Source: Pacific Climate Change Program Partners (2011)

149. Average temperatures will continue to rise with an increase in number of hot days and warm nights and decline in cooler weather. There is uncertainty with rainfall projections as model results for Samoa are inconsistent, but the projections indicate decrease in dry season rainfall and increase in wet season rainfall over the 21st century. This is related to the projected intensification of the Pacific Convergence Zone; drought projections are likewise inconsistent for Samoa. General decline in number of cyclones on a global scale by end of 21st century, but likely increase of average maximum wind speed of cyclones between 2% and 11% and increase in rainfall intensity of about 20% within 100km of a cyclone center. For Samoa, projections show decrease in frequency of tropical cyclones by the late 21st century but an increase in the proportion of more intense storms.

10 Pacific Climate Change Program Partners (PCCPP) 2011. Current and future climate of Samoa. Pacific Climate Change Science Program, International Climate Change Adaptation Initiative. www.pacificclimatechangescience.org

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150. The World Bank’s Natural Disaster Hotspots study identifies Samoa as 30th in the world for most exposed to three or more hazards.11 Nearly three-quarters of Samoa’s population lives on the coast exposing to them to coastal hazards such as cyclones, tsunamis, flooding and storm surges.

5.1.5 Hydrology

151. The modelled hourly discharge series from the node at 2.5 km downstream Samasoni Weir was selected to represent the existing hydrological regime of the lower Vaisigano River, and to characterise the degree of flow alteration that has occurred relative to the natural condition, with no hydropower off-takes. This location is between Samasoni Weir and Samasoni Power Station, so the river is impacted by diversion of water at the weir to a pipe that returns the water to the river downstream at the power station. Samasoni hydropower scheme was commissioned in 1982 and has a design discharge of 1.29 m3/s (JICA, 2003, p. 4-3). Other locations on the river system would be impacted by the current operation of hydropower plants to varying degrees, depending on the proportion of water diverted from upstream. Analysis of hydrological time series was undertaken for other locations for the environmental flow assessment (Elvey and Gippel, 2019).

152. The mean daily flow calculated for each day of the year demonstrated that although the current regime retained the natural seasonal distribution of flows, the mean flows for each day of the year were lower by about 1 – 2 m3/s, which represents a reduction of about 80 percent in the low flow period, and about 30 in the high flow period. The flow duration curve (Figure 5.9) illustrates the same impact, suggesting that the impact diminishes only at high flows.

Figure 5.9: Daily Mean flow 2.5 km d/s Samasoni Weir for modelled natural & current scenarios

Note: Calculated from 48-year long hourly modelled time series

Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

11 World Bank. 2005. Natural disaster hotspots: A global risk analysis (Washington D.C)

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153. Low flow indices (minimum hourly discharge, and flow exceeded for 95% of the time) and baseflow index (flow exceeded 50 percent of the time) for each month indicate that under the current regime, flow is precariously low relative to the natural regime in the months July to December, and low flows are dramatically reduced from natural in the high flow season (Error! Reference source not found.).

Figure 5.10: Flow duration curve 2.5 km d/s of Samasoni Weir for modelled natural & current scenarios

Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

154. High flow indices (flow exceeded for 1% and 0.1% of the time) for each month indicate that moderate flood flows are not greatly altered under the current regime relative to the natural regime, although small flow events (freshes) have been noticeably reduced in every month. Flood frequency analysis suggests that for any recurrence interval, peak flood magnitude has only been slightly reduced under the current regime relative to the natural regime.

155. The annual time series of annual flow indicates that the total flow each year under the current regime is on average 54 percent lower than under the natural regime, with the maximum reduction in any year being 65 percent (Figure 5.11). The annual peak hourly discharge under the current regime was on average 5.2% lower relative to the natural regime, with the maximum reduction in any year being 15.7 percent.

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Figure 5.11: Low flow indices (minimum hourly discharge and flow exceeded for 95% of the time) and baseflow index (flow exceeded 50 percent of the time) for each month at 2.5 km downstream of Samasoni Weir for the modelled natural and current scenarios

Note. Calculated from 48-year long hourly modelled time series

Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

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156. The flow health indicators were calculated using default statistical parameters, with the exception that the high flow season was manually specified as extending from November to May inclusive, consistent with the definition of the wet season by Elvey and Gippel (2019). As would be expected from the results of the other statistical comparisons made above, the integrative index classified the Vaisigano River 2.5 km downstream Samasoni Weir highly modified from natural, with scores for 5 of the nine indicators persistently in the very large deviation class (0.0 – 0.2) (Figure 5.12).

157. Less impacted aspects of the flow regime were Persistently higher (an indicator of unseasonal regulated irrigation flows), Seasonality flow shift, and Persistently very low (an indicator of unnatural cease to flow). Flood Interval indicator suggested a long periodic impact covering over half of the series (Figure 5.14). The median annual flow health score over the entire modelled series was 0.29 (Figure 5.13), which is within the large deviation class.

Figure 5.12: Partial duration series flood frequency for Vaisigano River 2.5 km d/s of Samasoni Weir

Note: For the modelled natural and current scenarios, based on 4th order polynomial curves fitted to frequency data from 45 years of modelled peak daily discharge data (2013 – 2057)

Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

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Figure 5.13: Annual flow & annual peak hourly discharge - Vaisigano River 2.5 km d/s Samasoni Weir

Note: For the modelled natural and current scenarios. Calculated from 48-year long hourly modelled time series Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

Figure 5.14: Flow health individual and combined flow deviation indicator scores - Vaisigano River 2.5 km d/s of Samasoni Weir for modelled current scenario relative to the natural scenario

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158. Overall, the hydrological analysis, including application of Flow Health, suggested that the Vaisigano River at 2.5 km downstream of Samasoni Weir is highly impaired relative to natural, and the impairment is persistent from year to year. The data strongly suggest that the river would also have experienced impaired ecological health due to the existing degree of flow regulation. Some reaches of the river system would not be impacted to the same degree, but others might be impacted to a greater degree.

5.1.6 Tectonic setting / Seismology

159. The Samoa Archipelago is part of a physiographic area known as Polynesia, a triangular area bounded by the Hawaiian Islands, New Zealand, and Easter Island. Within Polynesia, many volcanic island chains intersect. The Samoan Ridge is located near the convergent margin of the Pacific plate and the Fiji Plateau, west of the Tonga Trench. The northern boundary between the Fiji Plateau and the Pacific Plate is a transverse boundary, which is being sheared in a west-to-east trend north of the Tonga trench (also called the Kermadec - Tonga trench). The Tonga Trench is a west dipping subduction zone located less than 200 km south of Samoa (Figure 5.15).

Figure 5.15: Tectonic Setting of Samoa

Source: Alaoa Dam Technical Feasibility Report (Entura 2018)

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160. The Samoan Islands were formed as a result of a crustal plate (the Pacific Plate) moving slowly over a stationary hotspot. Hotspots are localized areas where hot mantle material wells up towards the surface of the earth. Crustal regions over these hotspots may experience volcanic eruptions and geothermal activity. In the Samoa Archipelago, the Pacific Plate is moving westward across a hotspot; thus, the easternmost Samoan Islands are the youngest, least eroded islands of the chain. The entire Samoan chain stretches east to west along the crest of the Samoan Ridge for more than 485 km of high volcanic islands, atolls, seamounts, and submerged reef banks.

161. Table 5.3 provides the hazard spectra for a dam proposed for Fuluasou site produced by GNS Science in New Zealand. The foundation rock at Alaoa site is similar to the Fuluasou site and therefore the results are considered to be reasonable for this feasibility study. Figure 5.16 shows the PGA hazard curve for Fuluasou dam site prepared by GNS Science in New Zealand.

Table 5.3: Hazard spectra adopted for Alaoa Dam

Figure 5.16: PGA hazard curve adopted for Alaoa Dam (POE based on 50 years)

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162. This same PGA hazard curve will be adopted for the Alaoa multi-purpose dam project. The return period values were converted to probabilities of exceedance (POE) in 50 years using the equation:

POE = 1 – exp^ (-(50) *1/return period)

Equation 1: Return Period – from Seismic Hazard Curve

163. The dam will be designed for an annual exceedance probability (AEP) of 1 in 10,000 years earthquake, which is typical based on international standards for a High hazard dam. The values for the peak ground acceleration (PGA) that the dam and the appurtenant structures will be taken from the site- specific seismic hazard assessment report undertaken by GNS Science for the Fuluasou Dam in Samoa. The 1 in 10,000-year PGA given in this report is 0.37g.

5.1.7 Geomorphology

164. The island of Upolu, Samoa is mountainous, with an elevation range from sea level up to 1158m (Figure 5.17). The Vaisigano River headwaters are on the central ridge of the island, and the river flows northwards, approximately in the middle of the island. It is the largest river on Upolu, with a catchment area of 34.4 km2 and mainstream length of approximately 14.1 km. The lower Vaisigano River flows through central Apia and it is of key importance in providing both water supply and power generation for the urban area.

Figure 5.17: Topography of Upolu, Samoa, showing location of Vaisigano River catchment

Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

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165. The Vaisigano River catchment is roughly wedge shaped with the upper catchment approximately 7 km wide. The Mulivai and Vaivase catchments are situated to the west and east respectively. The river rises on the main divide of Upolu at 1158 m asl (metres above sea level) at Mt. Fito and comprises four main tributaries, the western, middle and middle-eastern and eastern branches which merge to a single channel at Alaoa, about 5 km above its estuary in Apia Bay. These tributary names were used in this report for convenience. Local stream names were indicated on a map in Freeman (1944). The eastern branch was known as Soaga Stream, which had upper tributaries named Maualuga Stream and Vai o Le Fe'e. Soaga Stream is also named as such on the geological map of Upolu produced by New Zealand Geological Survey (1958). The middle-eastern branch was known as Puale'ile'i River. Soaga Stream and Puale'ile'i River joined to form the Vaisigano River. The western branch was named Puao River on the map of Freeman (1944) but was named Vaisigano River on the geological map of the New Zealand Geological Survey (1958).

166. The catchment of the Vaisigano River is deeply dissected. The drainage lines emerge from amphitheatre-headed canyons, with deep poorly graded valleys (Kear and Wood, 1959). The relief of the valleys in the vicinity of the proposed Alaoa Dam in the order of 200m (Figure 5.18). The lower 0.5 km of the Vaisigano River is tidal. The natural lowland floodplain of the Vaisigano River is now mostly alienated from the river due to the urban development of Apia, with associated flood protection works.

Figure 5.18: Elevation of the area in the vicinity of the proposed Alaoa Reservoir

Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

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167. As shown on Figures 5.17 and 5.18, the Vaisigano catchment has a high proportion of very steep hillslopes, which in combination with the steep stream gradients renders it conducive to rapidly rising floods following heavy rain, as well as potentially high sedimentation loads. The upper 2.0 km portion of the Vaisigano catchment descends rapidly at a slope of about 33%, which then changes to 7% for the next 5.6 km (Entura, 2018) (Error! Reference source not found.). The valleys in which the proposed Alaoa dam reservoir would be set are very steeply sloping. The slopes are in the range that would pose a risk of slope instability.

168. Rainforest is the predominant vegetation in the upper part of the catchment. Sixty eight percent of the Vaisigano catchment is forestry. The lower flanks of the catchment are a mixture of plantations, scrub, grazing lands and settlement. The river basin is bounded to the south by the central chain of volcanic cones that form the Upolu ridge.

169. Within Apia Harbour, sediments range from fine to medium sand to silt and mud (Gauss, 1981, reported by Solomon, 1994), while sand predominates in the outer harbour (Solomon, 1994). Richmond (1992) reported the presence of a shallow sub/intertidal delta at the mouth of the Vaisigano River. The river appeared to deposit its coarse bedload (sand/gravel and cobble) within 150 m of the mouth, beyond which silt and clay was deposited. Waves generate a net longshore current which moves a mixture of carbonate and volcanic sand east to west. The source of this sand is the reef flat (Solomon, 1994).

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Figure 5.19: Slopes in the vicinity of the Vaisigano River catchment and the proposed reservoir site

Source: Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

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170. Solomon (1994) used air photo interpretation, literature review and ground survey to develop an understanding of the geomorphic processes influencing the coastal and nearshore sedimentary systems of Apia Bay. The focus of the study was the Apia Harbour area and Mulinu'u Peninsula immediately to the west. Solomon (1994) reported that small scale mining of beaches has been practised in Samoa for a considerable time. Large scale dredging adjacent to Mulinu'u Point commenced sometime after 1970. Solomon (1994) also reported that the harbour had been dredged in order to perform land reclamation and to maintain navigable depths, and sediment deposited at the mouth of the Vaisigano River had been removed regularly by heavy equipment. Major dredging and construction began in Apia Harbour in 1964 (Gauss, 1981, reported by Solomon, 1994) when the main wharf was constructed and the land area to the west of the Inner Harbour was reclaimed. Historical aerial photography indicates the extent of enclosure of the harbour (Figure 5.20). Apia Bay, although open to the sea, was partially protected by fringing reefs, but the reclamation, mostly completed by 1970, further enclosed the harbour.

Figure 5.20: Time series of selected historical aerial photographs of Apia Bay

Note the flood sediment plume in the Bay emerging from the Vaisigano River in the 2018 photograph

Source: 1954, 1970 and 1987 extracted from Solomon (1994) and rectified; 2018 is World Imagery in Volume 2 – Annex E Geomorphic Impact Assessment (Fluvial Systems 2019)

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5.1.8 River sediment charatcter, transport and deposition

171. Suspended sediment load. The existing suspended sediment load of the proposed Alaoa Dam catchment was estimated using the three different empirical relationships of Holst Rice et al. (2016), one based on suspended sediment concentration as a function of instantaneous discharge, one on event suspended sediment load as a function of event peak discharge, and the other on event suspended sediment load as a function of event total discharge.

172. The 48-year modelled hourly time series of dam inflows was converted to suspended sediment concentration using the relationship of Holst Rice et al. (2016), capping maximum suspended sediment concentration at 9,000 mg/L (required on only 10 instances over 48-years) and assigning zero concentration to discharges less than 0.1 m3/s (0.54% of the time over 48-years). The hourly sediment load was then calculated as discharge multiplied by concentration. The estimates of sediment load were then summed to annual loads for water years, with a mean value of 8,867 tonne/yr (range 1,636 – 95,120 t/yr), or a specific yield of 539 t/km2/yr.

173. The 48-year modelled hourly time series of dam inflows was analysed using spells analysis to isolate flow events with discharge exceeding 1 m3/s, and event independence defined by an interval of 7- days between peaks. This produced 271 independent events. The total discharge of each event was calculated and then converted to sediment load using the relationship of Holst Rice et al. (2016). The estimates of sediment load were then summed to annual loads for water years, with a mean value of 1,269 tonne/ yr (range 463 – 2,160 t/yr), or a specific yield of 77.2 t/km2/yr.

174. The estimate based on event peaks was made comparable with that based on total event discharge by extracting the largest 271 independent event peaks from the 48-year modelled hourly time series of dam inflows. The peak discharge of each event was then converted to event sediment load using the relationship of Holst Rice et al. (2016). The estimates of sediment load were then summed to annual loads for water years, with a mean value of 108 tonne/yr (range 3.4 – 1,863 t/yr), or a specific yield of 6.6 t/km2/yr.

175. Bed material particle size distribution. The median size of bed material found in the river system was large cobble class at the two headwater sites upstream of the proposed Alaoa Dam site, and small cobble class at the other sites. However, the range of particle size at each site was large, covering sand to boulder size classes. The poorly to moderately sorted nature of the bed material, characterized by the Folk and Ward (1957) sorting coefficient, suggests that the source of bed material was local, and the distance the material had been transported in the river system was relatively short. Exposed bedrock was prominent upstream of Samasoni Weir and upstream of the inundation zone east branch.

176. Bed material transport. The Meyer-Peter and Müller (1948) equation was applied to the 245 m reach 3.4 kilometres downstream Samasoni Weir that was surveyed and modelled using the one- dimensional HEC-RAS hydraulic model. Nine of 29 surveyed cross-sections were selected to represent the bedload transport process. The results indicated that bedload transport rate was highly variable within the reach, as dictated by the longitudinally variable hydraulic capacity of the flow. The central section of the reach had very low sediment transport capacity, while the downstream section of the reach, which had higher slope, would transport bed material at lower discharges, and would transport bed material at a higher rate.

177. The median bed material transport conditions of the modelled reach were represented by cross- section 26, at 235 m chainage. A rating curve was established for this cross-section to predict bed material transport rate as a continuous function of discharge, although transport did not commence until a flow rate of 40 m3/s was exceeded (i.e. the threshold flow to initiate sediment transport). This rating curve was applied to the 48-year hourly modelled discharge series for the node at 2.5 km downstream Samasoni Weir. The results indicated that annual bed material transport load was 4 to 5 orders of magnitude lower than the suspended sediment transport load. Also, the current rate of bed material transport was similar to that under natural conditions.

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5.2 Biological Environment

5.2.1 Overview of ecology

178. It is estimated that Samoa supports 775 native vascular plant species of which approximately 30% of the angiosperms are endemic. There are about 280 genera of native angiosperms. In addition, there are about 250 introduced plant species and 47 threatened plants. Samoa’s fauna consists of 21 butterfly species, 11 species of reptiles, 43 resident bird species eight of which are endemic, and three flying fox species (Samoa NBSAP 2001). Samoa’s unique biodiversity is a result of its geographic isolation, which has led to the evolution of unique species and communities of plants and animals, many of which are indigenous to only one island or island group within the Pacific region. These species usually have small population sizes, making them particularly vulnerable to loss from overexploitation and habitat degradation. 11 terrestrial and 65 marine species found in Samoa are listed as globally threatened on the 2009 IUCN Red List of Threatened Species. It is thought that the true number of threatened species in Samoa is significantly higher than this.

5.2.2 Overview of flora

179. About 25% of the plants found in Samoa are endemic and 32% are endemic to the Samoan archipelago. A further 500 or so species of plants have been introduced to the islands since the first Samoans brought the coconut, taro and other species for cultivation about 3,000 years ago. Currently about half the plants in Samoa are exotic. While some of these plants are beneficial for agriculture, others are considered destructive weeds. A 1992 survey classified Samoa’s vegetation into 19 plant communities within five broad categories, as described below.

180. Littoral vegetation. Four communities of vegetation situated on the seashore were recognised: herbaceous strand or beach; littoral shrub-land; Pandanus scrub; and littoral forest whereby much of these types have been lost or degraded. The best remaining examples are at Aleipata Islands, O Le Pupu-Pue National Park and sites on the South (central) coast of Savai’i.

181. Wetland vegetation. Four communities are recognised: coastal marsh; montane marsh; mangrove scrub/forest; and swamp forest. There has been a very serious loss of wetlands, particularly in the lowlands, and only a few intact areas of each type remain.

182. Rainforest. Four communities are recognised on an altitudinal gradient: coastal; lowland; montane; and cloud forest. Cloud forests are restricted to Savai’i with the summit reaching over 1800 m. The few remaining significant areas of coastal forest are at the Aleipata Islands, Apolima and possibly Tafua Crater. The montane habitat is considered to have the richest flora of any forest community in the country. On Upolu, no montane sites were found that had good forest or were recovering (from cyclone damage) and there was substantial impact from several weeds. On Savai’i, the forests are recovering faster at higher elevations where there is little human activity, whereas the process is much slower at lower areas where forest cutting has added to the problem.

183. Volcanic vegetation. Two communities--lowland volcanic scrub and upland volcanic scrub--are recognised and these occur only on recent lava flows on Savai’i.

184. Disturbed vegetation. Four communities derived from a combination of human activities and weather are recognised: managed land; secondary scrub; secondary forest; and fernlands.

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5.2.3 Overview of avifauna and fauna

185. Bird Life International records 81 bird species in Samoa. This includes 31 breeding native land birds, one possibly extinct native land bird (the Samoan Moorhen), 4 breeding introduced birds, approximately 10 breeding seabirds and 35 migrants or vagrants. Nine of the land birds are endemic to Samoa and another seven are regional endemics or near endemics.

186. Twelve species are globally considered to be Restricted Range species, but not classed as of immediate conservation risk. Six species are considered to be of national conservation concern as determined through the National Biodiversity Strategy and Action Plan.

187. Sea/shore birds. There is a gap in the knowledge of population numbers and breeding status of seabirds in Samoa making it difficult to review and update the existing list of seabird species of conservation concern. Based on the available literature, approximately 12 seabird and shorebird species that are of global or national conservation concern have been recorded in Samoa. Several seabird species of global concern are either passage migrants, visitors or status unknown in Samoa. These include the Phoenix Petrel (Pterodroma alba); Tahiti Petrel (Pseudobulweria rostrata); Collared Petrel (Pterodroma brevipes) and Polynesian Storm Petrel (Nesofregetta fuliginosa). The globally threatened Bristle-thighed Curlew (Numenius tahitiensis) is a regular northern winter migrant in small numbers.

188. Bats. There are 13 species of terrestrial mammal now present in Samoa. Of these, only three are native, two flying foxes (or fruit bats), the Samoan Flying-fox (Pteropus s. samoensis) and the Tongan or White-necked Flying-fox (P. tonganus). A small insectivorous bat, the Sheathtailed Cave Bat (Emballonura semicaudata) is now believed to be extinct in Samoa. The flying foxes are important for the long-term survival of the forests as they pollinate the flowers of many species and also disperse the seeds of the fruits that they eat throughout the forest. It has been estimated that almost one in three Samoan forest trees depend on flying foxes in some way.

5.2.4 Overview of protected areas and key biodiversity areas

189. Key biodiversity areas (KBA) support the regular occurrence of one or more globally threatened species assessed as critically endangered, endangered, or vulnerable according to the IUCN Red List. Terrestrial KBAs cover a total of 940 km2 or approximately 33% of the total land area of Samoa, including representation of 12 of the 13 native terrestrial vegetation communities in the country. The seven marine KBAs cover approximately 173 km2 or 23% of the inshore reef area of Samoa. Currently, six of the eight terrestrial KBAs and three of the seven marine KBAs have been completely or partially established as conservation areas by the Government of Samoa or by local village communities and two additional KBAs have small community-based fisheries sites within their boundaries (Figure 5.21).

190. The first National Park established in Samoa was the O Le Pupu-Pue National Park in Togitogiga, in 1978. Two new national parks have since been established, including Mauga o Salafai, the first to be located on Savai’i, and Lake Lanoto’o which is the first Ramsar Convention Wetland site in Samoa at the center of the volcanic ridge on Upolu. Protected forest area consists of existing and proposed national parks and nature reserves, community conservation areas. All forest area outside protected forest is considered production forest.

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Figure 5.21: Terrestrial key biodiversity areas and native vegetation for Upolu and Savai’i

Source: Priority Sites for Conservation in Samoa: Key Biodiversity Areas12

191. The ecosystems and habitats of the area started changing when it was originally cleared around the Alaoa area during the establishment of the water reservoir and later the hydro power plants at Alaoa and Fale o le Fee in the late 1970s. Around the same time, families from Maagiagi and Vailima started clearing some of the lands along the riverbanks for plantations. To date, several new and old plantations are still present along the riverbed and the ridges along the project influence zone.

192. Cyclone Ofa in 1990 and Cyclone Val in 1991 brought about a dramatic change in the composition of the indigenous forests as many of the trees along the riverbanks and the ridges fell and were later replaced by fast growing alien invasive species such as Albizia falcataria, and rubber trees Funtumia elastica and Castilla Elastica. The spread of the taro blight from around 1993 meant most of the areas cleared for taro plantations were left fallow and were quickly converted into secondary forests dominated by the alien invasive trees.

12 https://www.sprep.org/att/IRC/eCOPIES/Countries/Samoa/191.pdf

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193. Cyclone Evan in 2012 and Cyclone Gita in the beginning of 2018 brought about major flooding within the Vaisigano River leading to landslides along the ridges and further destruction of the secondary forest in the area to what the area is now widely open dominated by vines and shrubs and fast-growing invasive rubber trees.

194. For the Upland Forest of the Vaisigano Watershed Area, the forest damage from Cyclone Ofa and Cyclone Val in 1990 and 1991 has changed the make up to what is now predominantly covered by dense thickets of the native invasive shrub Cestrum nocturnum with some of the big forest trees interspersed along the area. Part of the top area was also replanted through a watershed regeneration program in the late 1990’s and presently mostly with native tree species.

5.2.5 Apia Catchment KBA and the project area

195. The project area is located within the wider Apia Catchment KBA and shown in Figure 5.22. The total Apia Catchment KBA area is 8,336 ha while the proposed inundated zone within the project area is slated to cover only 20ha. The Vaisigano Watershed is one of three main watersheds in what has been identified as the Apia Catchment Key Biodiversity Area in the Samoa National Biodiversity Strategy and Action Plan. The Fuluasou and Leafa watersheds lie on the west of the Cross-Island Road. Along with the main watersheds, the Apia Catchment KBA also includes the only legally protected area which is the Mt Vaea Scenic Reserve and Robert Louis Stevenson Memorial Reserve. The Mt Vaea Scenic Reserve is outside the project area of influence.

Figure 5.22: Apia Catchment Key Biodiversity Area

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196. The Apia KBA is not a legally protected area but has been identified in the National Biodiversity Strategy and Action Plan as amongst the important area for biodiversity conservation (Table 5.4). The Apia Catchment KBA especially in the higher elevation of above 600m is where most of the data presently available recognises as being an area having high biodiversity and hold important ecological services functions such as water supply for the upper-catchment where there is limited to no direct human intervention. Within this higher elevation area, most of the critically endangered flora and fauna of Samoa have been recorded over the past. These include, a good population of the critically endangered Tooth- billed pigeon (Manumea), the presence of the threatened Mao, and the Samoan Ground Dove, birds as well as some of the other near threatened bird such as the Samoa Triller, the Samoan Robin, and the Red- Headed parrotfinch. Furthermore, some recent expeditions into the top of the Apia Catchment KBA has found threatened Samoan native palm.

197. Certain areas of the KBA/IBA such as the Mt Vaea Nature Reserve, Lake Lanutoo National Park and Upper Vaisigano Watershed area have been well surveyed by different groups. From these surveys, populations ranging in the 20s to 30s of the globally threatened Tooth-billed Pigeon and Mao have been recorded. Other trigger species such as the Samoan Flycatcher, Samoan Triller., Many-coloured fruit dove and Polynesian Starling were also recorded in good densities. Population densities for the Red-headed Parrotfinch were the highest in this site during the IBA field survey (Schuster, 2010).

Table 5.4: Apia Catchment Key Biodiversity Area

Site Island Faipule Approx. Current Protection IBA Terrestrial Threats Name District area (Ha) Status (Y/ trigger species N) in site

Apia Upolu Vaimauga 8336ha Partly protected in Y Samoan Bush Invasive catchment west, Lake Lanoto’o Palm (Niu vao), species, Faleata, National Park and Mt Tooth-Billed hunting, Siumu Vaea Scenic Pigeon development Reserve. Some (Manumea), conservation effort by Ground Dove MNRE’s watershed (Tuaimeo), Mao management section (Maomao), Samoan Broadbill (Tolaifatu), Samoan Flying Fox (Pea vao), Thaumatodon hystricelloides (Sisi) Source: Conservation International (2010)

198. The project area of influence as shown in Error! Reference source not found. is located within the Vaisigano Watershed Area which is one of the three main Watershed Areas in the Apia Catchment Key Biodiversity Area (shown in Figure 5.21) which totals over 8,336ha. The Vaisigano Watershed Area extends from 220 m to over 1000 m elevation while the construction footprint will be located at the bottom end of the catchment at around 160 mASL with the upstream extending at approximately 240 mASL.

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Figure 5.23: Project area of influence

Source: Terrestrial Biodiversity and Habitat Assessment (Volume 2 – Annex B)

199. The terrestrial ecology assessment found that much has changed in the make-up of the vegetation and ecosystems in the Vaisigano Watershed as shown in the following Table 5.5 (Volume 2 – Annex B, Entura 2019).

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Table 5.5: Ecosystem types within the project area and survey sites

Location Ecosystem Types Project Non-native vegetation Influence This area has been heavily influenced by human intervention through clearing for plantations Zone leading to several patches of fallow lands along with existing plantations. Additionally, the impact of natural events such as cyclones and floods have also contributed to modify the previously lowland and ridge rainforest area to where now a few patches of forested areas are predominantly covered by invasive trees mixed with secondary forest trees and some remaining native forest trees. Maagiagi Non-native vegetation: this area is classified as settlements which includes residences, family plantations and some fallow lands. In some of the fallow lands, secondary forest is mixed with alien invasive species. Alaoa Non-native vegetation: this is highly modified as reflected by the dominance of secondary forest mixed and alien invasive species despite the appearance of a closed forested area. Plantations and fallow lands are also common along this site. Source: Terrestrial Biodiversity and Habitat Assessment (Volume 2 – Annex B)

200. The terrestrial flora surveys positively identified over 45 plant species although a few more of the undergrowth plant species could not be identified due to accessibility along the steep ridges. Of the species identified 15 were native species of trees of lowland rainforest and secondary forest ecosystems, and tree ferns common in mid altitude forests, and 5 alien invasive trees. Five varieties of food crops were identified growing in plantations and some fallow lands. The rest of the vegetation was made up shrub, weeds, vines and epiphytes.

201. Typical vegetation in the project area site and its immediate surrounding area shown in Plates 5.1- and 5.2 illustrate that the area has been modified over many years due to human clearings for plantations and from natural events such as cyclones and floods. The vegetation composition of the area is now predominantly open fallow areas which are covered by invasive vines Mikania micrantha (mile-a-minute) and Merremia peltata. In the areas where trees remain along the river edge, and the some of the ridges, they are primarily dominated by the alien invasive rubber trees Castilla elastica, Funtumia elastica and tamaligi Albizia falcataria. Native secondary native forest trees such as Hibiscus tiliaceus (fuafua), Kleinhovia hospita (fau), Cananga odorata (mosooi), Erythrina variegate gatae and Trema cannabira magele were present.

202. In open fallow lands, the vegetation is predominantly plantation crops of taro and banana with some taamua, ava, cocoa and coconut trees also present. In old plantation sites, the vegetation is covered by mile a minute and Merremia vines alongside weeds. Remnants of the original lowland and ridge rainforest species such as Pometia pinata (tava) and Dysoxylum samoensis (maota) which once dominated this forest type, are now only found scattered along the area and mostly along the ridges, due to plantation clearings, cyclones and floods.

203. West Alaoa stream: The area is predominantly open along the riverbed due to clearing for plantations and remnants of fallen trees from cyclones and floods. The vegetation is old plantation with regrowth made up of invasive pulu and tamaligi trees along with some secondary and mature forest trees.

204. Along the ridges in areas where recent landslides had occurred, these are predominantly covered by ground ferns, vines and shrubby vegetations. In areas with no signs of landslides, the vegetation is a mixture of invasive pulu trees, tamaligi trees, native mature and secondary forest trees.

205. East Alaoa stream: The riverbed area has predominantly been cleared for plantations as evident by the old banana and taro plantations in open areas. The large trees along this area the invasive pulu and tamaligi trees with few large native mature forest trees tava, mamalava, afa, and maota along with some secondary forest trees such as tavai, fuafua, mossoi. The steep ridges along this end which had not been cleared for agriculture are still dominated by native mature forest species of tava and maota.

206. Appendix 3 provides the list of plants observed within the project area.

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Plate 5.1: Fallow lands at the proposed inundated area

Plate 5.2: Fallow and plantation lands mixed with invasive tree dominated forest

5.2.6 Habitat in the project area

207. Vegetation. Approximately 24.4 ha of vegetation will be directly impacted by dam construction and operation through direct removal. This vegetation can be categorised into two broad vegetation types: secondary forest; and mixed plantation. A map of vegetation types is shown in Figure 5.24.

208. . Detailed plant lists, their importance for threatened bird species and phenological observations are shown in Table 5.6 and Table 5.7.

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Figure 5.24: Vegetation types in the project area

Source: Dr Briar Taylor-Smith and Dr Rebecca Stirnemann (October 2019)

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Table 5.6: Partial species list for mixed plantation: plantation with some large indigenous & exotics

Phenological

observations on Scientific name Common name Importance footprint Some flowering Contains Miiiiistletoe Decaisnea sp. Albizia sp. Tamaligi on site Critical food source for Mao Carica papaya Papaya Panama rubber Castilla elastica tree Cestrum nocturnum Ali'I o le po Cocos nucifera Niu Food source for Mao Decaisnea sp. Mistletoe Some Flowering (pers com Stirnemann pers obs) Food source for Manumea Dysoxylum sp. Maota (Stirnemann) Mountain ginger, Some flowering Food source for Mao Etlingera cevuga avpui vao on site (pers com Stirnemann) Food source for Mao Erythrina variegata Gatae (pers com Stirnemann) Merremia peltata Musa sp. Fa'i Homalanthus nutans Mamala Food source for Pigeons Theobroma cacao Cacao

Source: Dr Briar Taylor-Smith and Dr Rebecca Stirnemann (October 2019)

209. Approximately 6.6 ha of the project footprint comprises mixed plantation, comprising forest clearings with wild and cultivated crops such as taro, banana and cocoa. Trees include Panama rubber trees, albizia containing native mistletoe, wild bush banana, large tava and large Dysoxylum spp. Critical food-source species for mao and/or manumea observed within this vegetation type include: Mistletoe (Decaisnea sp); Dysoxylum sp.; Mountain ginger (Etlingera cevuga); Gatae (Erythrina variegata); and Maota (Dysoxylum maota).

210. Approximately 17.8 ha of the project footprint comprises secondary forest containing a mixture of indigenous and exotic vegetation. This vegetation type is located on steeper valley slopes and ridges. This vegetation is dense, has higher species diversity and contains some large native trees. A large number of invasive species are also present in this vegetation type (Table 5.7). Critical food-source species for mao and/or manumea observed within this vegetation type include those present in the plantation vegetation type but also: Tufaso (Dysoxylum samoense); Pua lulu (Fagraea berteroana); Mati (Ficus sp.); Laufao (Heliconia laufao); and Mamalava (Planchonella samoensis).

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Table 5.7: Partial species list for Secondary Forest: forest with a mixture of indigenous and exotics

Observations Scientific name Common name within Importance footprint Contains mistletoe Decaisnea sp - food Albizia sp. Tamaligi Some flowering source for Mao (Stirnemann pers obs) Amyema artensis Tapuna Angiopteris evecta Giant fern Cananga odorata Moso’oi Flowering Pigeons eat fruit (Whistler 2004) Canarium vitiense Ma’ali Castilla elastica Panama rubber tree Cinnamomum verum Tinamoni Cordyline fruticosa Ti vao Decaisnea sp. Mistletoe Some flowering Food source for Mao (Stirnemann) Fruiting Food source for Manumea Dysoxylum maota Maota nearby (Stirnemann pers obs) Food source for Manumea Dysoxylum samoense Tufaso (Stirnemann pers obs) Mountain ginger, Flowering Food source for Mao (Stirnemann Etlingera cevuga avpui vao on site pers obs) Fruiting and Fruit and flowers eaten by Mao Fagraea berteroana Pua lulu flowering (Stirnemann pers obs) Fruiting An important food source for Ficus sp. Mati nearby Manumea (Stirnemann pers obs) Flacourtia rukam Filimoto Fruits eaten by pigeons (Whistler 2004) Flueggea flexuosa Poumuli Fruits eaten by birds (Whistler 2004) Funtumia elastica African rubber tree Flowers and fruit food source for Mao Heliconia laufao Laufao (Stirnemann pers obs) Morinda citrifolia Nonu Nectar is favourite food of honeyeaters Myristica inutilis ‘Atone Fruiting Fruit eaten by pigeons (Whistler 2004) Pigeons sometimes eat the leaves Homalanthus nutans Mamala (Whistler 2004) Palaquium stehlini Gasu Fruit eaten by bats (Whistler 2004) Fruits important food source for Planchonella garberi ‘Ala’a pigeons and bats (Whistler 2004) Fruits are a major food source for Planchonella samoensis Mamalava pigeons and bats (Whistler 2004) Pometia pinnata Tava The seasonal fruits are eaten by Syzygium dealatum Asi vai pigeons and doves (Whistler 2004) Major food source for bats and Syzygium inophylla Asi toa pigeons (Whistler 2004) Syzygium Eaten by pigeons and bats (Whistler Nouveau Fruiting samarangense 2004) Flowering Fruits valuable food for pigeons Terminalia richii Malili near site entry (Whistler 2004) Trichospermum richii Makosina

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211. These vegetation types also provide foraging and roosting habitat for other bird species and bats. The two vegetation types mapped in Figure 5.24 will be directly impacted by dam construction and operation. An additional area of vegetation adjacent to the dam footprint will not be removed but is likely to be modified through edge effects.

212. Edge effects will be directly modifying the biota and are likely to result in long-term changes in their composition and structure. Unfortunately, there is virtually no data on the changing composition of forest remnants in Samoa. However, in New Zealand Microclimate effects do not extend beyond c. 20 m into the forest (Norton 2002). The microclimatic edge effect of 20 m in width was estimated for the footprint adding an additional 10 ha of impacted forest (Figure 5.24).

213. ). However, it is important to note edge effects are observed past this point and vegetation responses can be apparent up to 70 m into the forest for some variables (e.g. tree ferns and bryophytes) (Norton 2002). The responses of canopy invertebrates appear similar to those of vegetation, although the effect of edge on predator abundance appeared to extend into the forest for at least 100 m (Norton 2002). Studies, both in New Zealand and elsewhere suggest that edge effects of 50-100 m are a significant issue for small forest remnants in particular (Norton 2002).

5.2.7 Terrestrial habitat value and threat status

214. The footprint of the site was assessed for the presence of critical habitat, as defined by the SPS (ADB, 2009). The Alaoa site is modified exotic and native forest that provides habitat to three bird species of particular concern: mao, manumea or toothbilled pigeon (Didunculus strigirostris) and Samoan triller or miti tae (Lalage sharpei).

215. The Alaoa site is also habitat to the following range restricted bird species; Flat-billed Kingfisher (Todiramphus recurvirostris), Samoan Whistler (Pachycephala flavifrons), Samoan Fantail (Rhipidura nebulosa), Samoan Flycatcher (Myiagra albiventris), and Samoan Starling (Aplonis atrifusca) as well as the Red headed parrot finch (Erythrura cyaneovirens). Of these there is also some concern for the Samoan Broadbill and the Samoan red headed parrot finch. The threat status of these species is described in Table 5.8.

216. The Samoan broadbill has a very small range and a small population and is suspected to have declined owing to small-scale habitat loss for shifting agriculture (BirdLife International 2019). The Samoan populations of the newly defined red headed parrot finch E. cyaneovirens are widespread, though uncommon. Based on known records, the Samoan sub-population sizes are likely more than 1,000 mature individuals (BirdLife International 2019).

217. The flat billed king fisher has an unknown unquantified population trend. However, the population is not believed to be decreasing rapidly and it is not believed to approach the thresholds for Vulnerable. The Samoan whistler also appears to have a stable population trend though the population size has not been quantified (BirdLife International 2019).

218. The Samoan fantail and the Samoan starling both have a restricted range, however neither are believed to approach the thresholds for Vulnerable under the range size criterion and both populations appear stable (BirdLife International 2019).The two flying fox species (Table 5.8) both occurred in the footprint of the site. The Samoan flying fox is near threatened because it is range restricted and it needs special consideration, in contrast the Tongan fruit bat’s status is of less concern.

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Table 5.8: Threat classification listing for all species of concern

Group Common name Scientific name Threat classification Eco value Bird Manumea, Toothbilled Didunculus strigirostris Critically Endangered Very high pigeon Mao, Mao mao Gymnomyza samoensis Endangered Very high Near threatened (but Samoan triller, Miti tae Lalage sharpei High likely to be upgraded) Samoan broadbill/Flycat Myiagra albiventris Near threatened High cher Flat-billed Kingfisher Todiramphs recurvirostrs Least concern Low Samoan Whistler Pachycephala flavifrons Least concern Low- medium Samoan parrot finch E. c. gaughrani Near threatened Medium Samoan Fantail Rhipidura nebulosa Least concern Low Samoan Starling Aplonis atrifusca Least concern Low Bat Tongan fruit bat Pteropus tonganus Least concern Low Samoan fruit bat Pteropus samoensis Near threatened High

Source: Volume 2 – Annex J – Assessment of Ecological Effects: Birds and Bats (October 2019)

5.2.8 Avifauna – Mao

219. Site visits to the Alaoa site were undertaken by the project team between 10-21 September 2019. Members from EPC and MNRE were present during visits. Targeted surveys occurred for mao, manumea and Samoan triller. The time of year was appropriate for Mao. The timing was suboptimal for Manumea in the target catchment as none of the fruiting trees which attract them were fruiting. The survey timing was a little late for some of the other passerines which tend to breed earlier and therefore are not as responsive at this time. The timing was optimal for assessing nesting use of seabirds in the catchment. Additional birds of interest were recorded at an ad hoc basis.

220. The use of automated acoustic recording devices (ARDs) for detecting birds and other animals has increased rapidly in recent years. Advantages include the ability to estimate the number of species present at many sites simultaneously, the generation of a permanent and reviewable record over prolonged time periods, minimal disturbance to wildlife and the ability to sample the audible soundscape 24 hours per day. In total, a maximum of 80 hours of recordings can be generated for each point. Points for automatic recorders were established at random locations >200 m apart along randomly selected areas within the footprint. This distance allowed independence between the recorders. All recorders were set at high sensitivity and covered a period from in the morning from 6-10am and in the evening from 5-8pm. Recordings were analysed using ‘AvianNZ’ software to determine presence or absence per point.

221. Five acoustic sound recorders placed within the footprint all contained mao calls, the location of recording devices are shown on Figure 5.25Error! Reference source not found. and birds detected by recording devices shown on Figure 5.26. In addition, territorial pairs were found throughout the footprint of the site and the surrounding area over the survey period. One pair has the core of its territory where the dam wall would be built. Mao has extremely high territorial site fidelity and therefore it is expected this pattern to be consistent. A large number of the larger trees, invasive and native, contained mistletoe a plant which is strongly correlative with mao occurrence. No breeding behaviour was identified during the field survey; however, breeding occurs from April-Nov and only a single chick is produced in a season. Therefore, it is not unlikely breeding may already have occurred before the survey for this study was undertaken.

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Figure 5.25: Location of acoustic recording devices

Source: Volume 2 – Annex J – Assessment of Ecological Effects: Birds and Bats (October 2019)

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Figure 5.26: Location of birds detected by acoustic recording devices

Source: Volume 2 – Annex J – Assessment of Ecological Effects: Birds and Bats (October 2019)

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222. The Vaisigano catchment is one of five “first priority” sites for conservation of mao in Samoa. Only three of the five key sites have had recent mao sightings, in the Savaii uplands, at Lake Lanoto’o/Malololelei and in the Vaisigano catchment. Only lake Lanoto’o/Malololelei and the Vaisigano catchment are in Upolu. This makes these sites of particular importance for maintaining this species on Upolu.

223. Mao are known to occupy and breed within the Vaisigano catchment, and both adults and juvenile birds have been observed within or near the site at O le Fale o le Fe'e. Successful breeding is also known to occur in the eastern Vaisigano catchment where a long-term study was made of the species.

224. The Lake Lanoto’o and nearby Malololelei site has only a small area of suitable habitat for mao and can only maintain a few territories. The proposed project area is an important site where mao are potentially successfully breeding. Given the limited distribution of this species, and how few large native forest canopy trees remain on Upolu, any modification of habitat must be carefully managed to avoid adversely impacting the population.

5.2.9 Avifauna - Manumea

225. Field work conducted during as part of this survey did not detect manumea within the project site. This is a cryptic species with extremely low detectability and survey did not cover the fruiting period within the catchment. Manumea move around the landscape tracking the availability of fruit which can differ markedly in phenology across the landscape. Critical manumea habitat was identified in the Alaoa footprint with multiple large mature moata, a favoured feeding tree identified. During the survey period Aoa (Ficus prolixa), Moata (Dysoxylum moata), (Syzygium dealateum) and (Myristica inutilis) were found to be fruiting at low levels within 2 km of the footprint. However, in the Alaoa footprint no trees with ripe fruit were found during the survey. Because the trees in the footprint were not fruiting it is unlikely that manumea will be using the site for feeding during the survey period.

226. The absence of manumea sightings during the survey therefore cannot exclude the presence or absence of manumea from within the project site. Manumea have been observed outside this survey period within 1-2km of the footprint (Figure 5.27Error! Reference source not found.). It is likely that manumea would be feeding on species, such as moata, within the footprint during the fruiting season in this location.

227. Manumea have been detected within the Vaisigano catchment. Adult birds have also been observed flying in and of the Vaisigano catchment across Cross Island Road probably so they can access various mature fruits on which they rely. Manumeau have also been observed east and west of the Vaisigano catchment; at Tiapapata, Lake Lanoto’o and O le Fale o le Fe'e and by hunters directly above the proposed site.

228. The project site was found to contain mature Dysoxylum trees, an important food source of the species. Dysoxylum were locally common. It is therefore likely that the birds feed within the project footprint when these trees are fruiting.

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Figure 5.27: Recent Manumea observations around project site

Source: Volume 2 – Annex J – Assessment of Ecological Effects: Birds and Bats (October 2019)

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5.2.10 Other terrestrial species

229. Avifauna. A single Samoan triller was heard in the footprint of the dam. The habitat within the footprint is likely to be appropriate habitat for this species to breed. This endemic species occurs in forested areas, forest edges and clearings (Watling, 2004). Playback where the Samoan triller was previously found this species in only two sites (n=10). This species has become increasingly rare in Samoa and particularly in Upolu. However, it appears to respond positively to pest control (Stirnemann pers com). The Samoan broadbill was also found within the footprint and is likely to be breeding within the footprint.

230. In addition to the target birds of interest the footprint also supports breeding congregatory brown noddies (Anous stolidus) as well as white terns along the end of the eastern arm of the Vaisigano river within the footprint (Volume 2 – Annex J). A cave of breeding White-rumped Swiftlet (Aerodramus spodiopygius) is also located along this arm of the river.

231. A few Samoan broadbill were seen and heard during the survey period both inside and nearby the footprint. Calls indicated territorial pairs. The red headed parrot finch was also seen in the footprint and has been previously been observed nesting within 1km from the site. Flat billed king fisher, Samoan fantail and Samoan starlings were also seen in and around the site and footprint. No friendly ground doves were observed in the site or footprint area.

232. Bats. Both Samoan and Tongan fruit bats were observed in the footprint and surrounding area. Twelve observations of Samoan fruit bats were made in the footprint over the survey period. This is not surprising given that they are often seen breeding in the Fale o’le fe’e site less than 2km from the site. No bats were seen feeding in the footprint but given that none of the fruiting trees were ripe this was also not surprising

5.2.11 Aquatic fauna

233. The Apia KBA includes the forested headwaters of the catchments that flow through Apia which are mapped as montane rainforest while the lower slopes near the project site are mapped as disturbed forest. There are no aquatic trigger species in the Apia Catchments KBA and aquatic biodiversity is a key knowledge gap for all terrestrial KBAs in Samoa (Conservation International 2010). 13

234. Fish. Thirty-four freshwater fish species have been recorded in Samoa and the majority of these inhabit the zone between estuarine habitats and the lower course of rivers (Table 3.1). The majority of freshwater fish species in Samoa are widespread in the Pacific and Indo-Pacific area with the exception of Kuhlia salelea and Schismatobobius tuimanua14 which are endemic to Samoa and American Samoa (Keith et al. 2013; Keith et al. 2017), the latter species being recently described (Keith et al. 2017). The goby Stiphodon hydoreibatus is endemic to a limited region of the Pacific, having only been recorded in the Samoan islands and Futuna (Table 3.1). Tropical fish experts have concluded that further fish species are probably yet to be described in Samoa due to the low number of surveys that have been conducted (Jenkins et al. 2013) and the recent description of Schismatobobius tuimanua supports this (Keith et al. 2017). Kuhlia salelea (catadromous), Schismatobobius tuimanua (amphidromous), and Stiphodon hydoreibatus (amphidromous) are all migratory species which must move between freshwater and the sea to complete their life cycle.

13 This section draws extensively on the study commissioned as part of the project and reported in the document Aquatic biodiversity and habitat assessment (Feb 2019). See Volume 2 - Annex C. 14 Schismatobobius sp. was reported in the Vaisigano River by Atherton et al. 2013 but it is unclear if this is Schismatobobius tuimanua or another species were taxonomic verification is pending. Clarification has been sought from Phillippe Keith, a tropical fish taxonomic expert.

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235. Fifteen of the 34 freshwater species recorded in Samoa have obligatory migratory life histories. Most of the migratory species are amphidromous (breed in freshwater, larvae flow to the sea and juveniles return to freshwater to complete the life cycle) although four catadromous species are also present (adults live in freshwater and migrate to sea to spawn with juveniles returning to freshwater to complete the life cycle).

236. None of the fish recorded in Samoa are listed as threatened by the International Union for Conservation (IUCN) Red List, although the Mozambique Tilapia is considered near threatened within its native African range but is otherwise widespread throughout the world as an introduced species. The majority of the fish recorded in Samoa are assessed in the Least Concern category by the IUCN Red List, although several species are assessed as data deficient.

237. Samoa has a steep topography and only fish species that can climb above barriers are found upstream of the first significant waterfall (Keith et al. 2013). In Samoa, five fish species have been recorded which have the ability to climb past significant barriers and include four goby species in the sub-family Sicydiine (Sicyopterus lagocephalus, Sicyopterus pugnans and Stiphodon hydoreibatus) and two species of eel (Anguilla marmorata and Anguilla megastoma). These five climbing species are all migratory amphidromous (gobies) or catadromous (eels) species. The green riffle goby (Stiphodon elegans) is another amphidromous species which can also navigate past small to moderate obstacles.

238. Crustaceans. Nineteen freshwater crustacean species have been recorded from Samoa, all are widespread in the pacific and none are listed as threated by the IUCN Red List. Ten of the nineteen crustacean species have obligatory amphidromous migratory life histories and most of these have the ability to climb waterfalls and penetrate into the upper reaches of rivers. There are no published reports on Samoa’s non-crustacean freshwater macroinvertebrate fauna.

5.2.12 Previous aquatic surveys of the Vaisigano River

239. A previous aquatic fauna survey was conducted in the Vaisigano River catchment in 2013 as part of an initial environmental examination for small hydropower projects in Samoa (Atherton et al. 2013). The 2013 survey recorded seven fish species and one species of shrimp in the lower Vaisigano River in the vicinity of the Samasoni Power station.

240. Fish diversity was lower at the other sites which were all upstream of Samasoni Weir with only species with climbing ability recorded. No fish were recorded at the Alaoa intake on the middle branch of the river which the authors suggested was a result of flow diversion causing lengthy periods of zero flow in the channel downstream of the offtake (Atherton 2013). The endemic goby Stiphodon hydoreibatus was recorded in the Vaisigano River upstream of Samasoni Weir.

241. The diversity of crustacean species at the sites upstream of Samasoni Weir ranged from three to five species, all of which are migratory and have the ability to climb past barriers.

242. There are no other available reports on aquatic fauna from the Vaisigano River; however, an aquatic biodiversity survey conducted in 2008 included the two sites in the Vailima River which drains into Apia Bay approximately 600 metres to the west of where the Vaisigano River enters the bay (Jenkins et al. 2008). The sample sites for the 2008 survey were at approximately the same elevation as Samasoni Weir on the Vaisigano River (~110 mASL). Two eel species, Anguilla marmorata and Anguilla megastoma and the red-tailed goby Sicyopterus lagocephalus where the only fish species recorded (Jenkins et al. 2008). The survey in 2008 also recorded three prawn and three shrimp species (Jenkins et al. 2008).

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5.2.13 Ecology and status of migratory climbing species

243. Migratory species which can penetrate past waterfalls into the middle and upper catchments of rivers are the species which an instream dam are likely to negatively impact the most. As discussed above, six species of migratory fish and seven species of migratory crustaceans which can climb barriers have been recorded in the Vaisigano River (Table 5.11 and 5.12). The known distribution, habitat preferences, feeding associations and conservation statues of these migratory climbing species are summarised below.

244. Sicyopterus lagocephalus (red-tailed goby). Sicyopterus lagocephalus is the most widespread goby in the Sicydiinae sub-family being common throughout the Indo-Pacific area (Keith et al. 2015) and is assessed as a species of Least Concern by the IUCN Red List (IUCN 2012). Sicyopterus lagocephalus inhabit the lower to higher reaches of rivers where the adults generally live in areas of fast flowing water (130 to 160 cm/s) and at water depths between 20 and 40 centimetres over coarse bed materials (pebble size and greater) (Keith et al. 2015). Sicyopterus lagocephalus feeds by scraping algae from the rocky bottom and is amphidromous, reproducing in rivers with hatched larvae passively transported to the sea. To survive, the final larval stage must reach the sea in a maximum of 96 hours (Keith et al. 2015).

245. Developmental changes take place in the marine environment over approximately 130 to 240 days before freshwater flow into the coastal zones attracts post-larvae near river mouths to start migrating upstream (Keith et al. 2015). Re-entering freshwater initiates another series of morphological changes to adapt the fish to riverine habitats with the resulting juveniles adopting a benthic habit and the ability to climb over waterfalls using their adapted pelvic fins and mouth as a sucker.

246. Sicyopterus pugnans (fat-snout goby). Sicyopterus pugnans is a species of goby that occurs in Samoa, American Samoa and French Polynesia (Keith et al. 2015) and is assessed as a species of Least Concern by the IUCN Red List (IUCN 2012). Sicyopterus pugnans inhabits the lower to middle reaches of rivers and often co-occurs with S. lagocephalus (Keith et al. 2015). Sicyopterus pugnans lives in similar flow habitats to S. lagocephalus but is less rheophilic (i.e. species preferring to live in fast flow water) and more common in deeper areas over rock substrate (Keith et al. 2015). The reproductive development and migratory behaviour of amphidromous S. pugnans follows a similar pattern to S. lagocephalus.

247. Stiphodon hydoreibatus (climbing Stiphodon). Stiphodon hydoreibatus is a recently described goby (Watson 1999) that has only been found in Samoa and Futuna (Keith et al. 2015). This species has been recorded in the lower and middle course of rivers up to 200 metres in elevation, in slow flowing habitats with pebble and larger substrate where it feeds on benthic algae (Keith et al. 2015). There is no information on the population size or trends of this species as it has not been commonly found which may also indicate that it is naturally rare, and the IUCN conservation status of this species is assessed as Data Deficient (IUCN 2012). The reproductive development and migratory behaviour of amphidromous S. hydoreibatus is likely to broadly follow that described for S. lagocephalus.

248. Stiphodon elegans (green riffle goby). Stiphodon elegans is reported to occur in the lower course of rivers where it prefers coarse rocky substrates and slow to medium currents in pool habitats. It is an algal grazer with an amphidromous life history and occurs in French Polynesia, Samoa, Cook and Futuna (Keith et al. 2013).

249. Anguilla marmorata (giant mottled eel). Anguilla marmorata is catadromous eel that is common throughout the tropical and subtropical western-central Pacific and Indian Oceans and its IUCN conservation status is assessed as Least Concern (IUCN 2014). Anguilla marmorata occurs from estuaries to the higher reaches of rivers and also occurs in still waters (Keith et al. 2013). Adult A. marmorata migrate downstream to spawn in the open ocean and juveniles migrate back to the estuaries to begin their upstream migration between October and April with a peak in numbers in January and February which may coincide with the higher flows as the wet season builds (Keith et al. 2013). Prey items include fish and invertebrates, in particular crustaceans. Recent research indicates that migration up into rivers may not be an obligatory requirement for some populations of this species (Aria and Chino 2018).

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250. Anguilla megastoma (Polynesian long-finned eel). Anguilla megastoma is a catadromous eel which inhabits the higher reaches of rivers in the Pacific area, including the Solomon Islands, French Polynesia, Vanuatu, New Caledonia, Futuna, Cook, Samoa and Pitcairn (Keith et al. 2013). There is no quantitative information on its population status or distribution and little information about its ecology, and hence the IUCN conservation status of this species is assessed as Data Deficient (IUCN 2014). Adult A. megastoma migrate downstream to spawn in the open ocean and juveniles migrate back to the estuaries to begin their upstream migration between April and July (Keith et al. 2013). In rivers, A. megastoma feed on fish, crustaceans and other invertebrates (Keith et al 2013; IUCN 2014). Declines in populations of A. megastoma in French Polynesia have been attributed to water abstraction for hydropower plants and other infrastructure developments around watercourses blocking migration routes (IUCN 2014).

251. Macrobrachium aemulum (Noumea river prawn). An amphidromous prawn, occupying the lower to mid-course of rivers preferring areas of strong current (Keith et al. 2013). This species has an omnivorous feeding habit. After hatching in freshwater larval are carried by the current into the estuary or sea where development takes place before juveniles migrate back upstream. Macrobrachium aemulum is found in the Indo-Pacific region, including India, Vanuatu, New Caledonia, Futuna, Cook, Samoa and French Polynesia and its IUCN conservation status is assessed as Least Concern (IUCN 2014).

252. Macrobrachium gracilirostre (lollipop prawn). An amphidromous prawn, occupying the lower course of rivers where it is most active at night, sheltering under rocks. After hatching in freshwater larval are carried by the current into the estuary or sea where development takes place over a few weeks before juveniles migrate back upstream (Keith et al. 2013). This omnivorous prawn is found in the Pacific region including Taiwan, Philippines, New Caledonia, Futuna, Samoa and Fiji and its IUCN conservation status is assessed as Least Concern (IUCN 2014).

253. Macrobrachium latimanus (mountain river prawn). An amphidromous prawn, that reaches a maximum length of approximately 10 cm for females and 13 cm for males. Found in the medium to high reaches of rivers amongst coarse substrate in medium to strong currents and cascades (Keith et al. 2013). After hatching in freshwater larval are carried by the current to the sea where development takes place over a few weeks before juveniles migrate back upstream. This species is widespread in the Indo-Pacific region and its IUCN conservation status is assessed as Least Concern (IUCN 2014).

254. Macrobrachium lar (giant jungle prawn). An amphidromous prawn found from the lower to higher courses of rivers which can reach up to 20 cm body length. Reproduction takes place in fresh or brackish waters with larvae washed to sea before migrating back upstream as juveniles when they reach 30 to 35 mm in length. This omnivorous species is widespread in the Indo-Pacific and its IUCN conservation status is assessed as Least Concern (IUCN 2014).

255. Macrobrachium australe (koua river prawn). An amphidromous prawn, occupying the lower course of rivers and estuaries. Reproduction takes place in fresh or brackish waters and it has an omnivorous feeding habit. Macrobrachium australe is found in the Indo-Pacific region in Madagascar, Reunion Island, Indonesia, New Caledonia, Vanuatu, Futuna, Cook, Samoa and French Polynesia. This species is assessed as Least Concern by the IUCN (IUCN 2014).

256. Atyopsis spinipes (bamboo shrimp). An amphidromous shrimp, most often found in the mid to higher course of the rivers under waterfalls and small cascades (Keith et al. 2013). Post-larvae and juveniles migrate upstream and climb over waterfalls by crawling on humid substrates (Keith et al. 2013). Atyopsis spinipes has a microphage dietary pattern and it occurs in the Pacific region including Philippines, New Caledonia, Vanuatu, Fiji, Futuna and Samoa.

257. Atyoida pilipes (green lace shrimp). An amphidromous shrimp that prefers fast flowing habitat from the lower to higher courses of rivers. Atyoida pilipes is a detritivore and is found in the Pacific region including Philippines, French Polynesia, New Caledonia, Vanuatu, Futuna, Cook and Samoa (Keith et al. 2013).

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Table 5.9: Freshwater fish species recorded from Samoa Islands (Samoa and American Samoa)

Latin name English (E); IUCN status Distribution Life Habitat Samoan History name Lamnostoma Oscillated Least concern Widespread in Indo- EM polyophthalma sand-eel Pacific Estuaries

Psammogobius Sleepy goby Least concern India, Seychelles, Sri EM biocellatus (E) Lanka to Samoa, Vanuatu and New Caledonia Kraemeria samoensis Sand fish (E) Least concern French Polynesia, EM Estuary to river Tonga, Samoa and mouth Marshall Islands and the Seychelles Gambusia affinis Mosquitofish Least concern Native to USA, FS Coastal to (E) introduced throughout lower course of world rivers Ambassis miops1 Flag-tailed Least concern Widespread in Indo- EM Glassfish; Pacific Coastal, Lafa’ (S) estuaries and lower courses of rivers Moringua microchir Lesser thrush- Not assessed Widespread in Indo- EM eel; Fa’ fa’ Pacific

Microphis argulus Least concern Widespread in Indo- EM Pacific Microphis brachyurus Short tailed Least concern Widespread in Indo- EM pipefish (E); Pacific Estuaries and Tia’i pape (S) lower courses of rivers

Microphis retzii Ragged-tail Least concern Widespread in Indo- EM

pipefish (E) Pacific

Poecilia mexicana1 Shortfin molly Not assessed Intro. from Central FS

(E); Fo vai (S) America, now

widespread in

Polynesia

Kuhlia mugil Barred flagtail Least concern eastern Indian Ocean EM (E); Safole to French Polynesia (Sa) 1 Kuhlia salelea Flagtail (E) Data deficient Endemic to Samoa COB Salele (Sa) and American Samoa Butis butis Duckbill Least concern Widespread in Indo- EM sleeper Pacific Hypseleotris Rainbow prigi Data deficient Widespread in the A cyprinoides/guentheri (E); Mano’o- Pacific fovai (S)

Ophiocara Northern mud Least concern Widespread in Indo- A porocephala gudgeon (E) Pacific

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Latin name English (E); IUCN status Distribution Life Habitat Samoan History name Eleotris melanosoma1 Broadhead Least concern Widespread in Indo- A sleeper (E); Pacific Mano’o-pala Estuaries and (S) lower courses of rivers Eleotris fusca1 Broadhead Least concern Widespread in Indo- A sleeper (E); Pacific Mano’o-pala (S) Redigobius bikolanus Speckled Least concern Widespread in the EM gobie (E) Pacific Ocean

Mugilogobius none Least concern Fiji, Samoa, Tonga, FS notospilus Solomon Islands, Vanuatu, New Caledonia, New Guinea and Australia Schismatobobius none Not assessed Endemic to Samoa A Lower course tuimanua and American Samoa of coastal streams just above tidal influence Anguilla obscura Pacific short- Data deficient Widespread in Indo- C finned eel (E); Pacific Tuna (S) Lower course of rivers Poecilia reticulata Guppy (E) Not assessed Introduced throughout FR the world from America Carassius auratus Goldfish (E) Least concern Originally from China, FR Stillwater intro. throughout the habitats world Stiphodon elegans1 Mano’o-vai (S) Least concern French Polynesia, A Samoa, Cook and Futuna Lower reaches Awaous ocellaris1 Mano’o apofu Least concern Widespread in the A of rivers (Sa) Pacific

Stenogobius O’opu (Sa) Least concern French Polynesia, A genivittatus1 Samoa, Cook Islands

Limia vittata1 Cuban limia Not assessed Introduced from Cuba lower courses (E) of rivers, lagoons, lakes and swamps Oreochromis Mozambique Near Introduced from Africa, FS Estuaries to mossambicus1 Tilapia (E) threatened (in now widespread wide range of native African around the world river habitats range) Kuhlia rupestris1 Rock flagtail Least concern Widespread in Indo- A Lower and (E) Sesele Pacific middle course (Sa) of rivers Anguilla marmorata1 Giant mottled Least concern Widespread in Indo- FC Estuaries to eel (E); Tuna Pacific higher reaches (S) of rivers

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Latin name English (E); IUCN status Distribution Life Habitat Samoan History name Sicyopterus Red-tailed Least concern Widespread in Indo- A Lower to higher lagocephalus1 goby (E); Pacific reaches of Mano’o (S) rivers, prefers fast flow Sicyopterus pugnans1 Mano’o (S) Least concern Samoa and French A Lower to Polynesia medium reaches of rivers, prefers fast flow Stiphodon none Data deficient Samoa and Futuna A Lower to hydoreibatus1 medium reaches of rivers Anguilla megastoma Polynesian Data deficient Widespread in the C Higher reaches longfinned-eel; Pacific area of rivers Tuna (S)

1 Species recorded during the aquatic season surveys for this project; Species are listed in order of habitat preference, starting with estuarine and lower riverine species to species which only occur in the higher reaches. Source: EIA Volume 2 – Annex C Aquatic Biodiversity and habitat Assessment (Entura 2019)

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Table 5.10: Freshwater crustacean species, IUCN Red List status and habitat preferences

English (E); IUCN Life Latin name Samoan name Habitat/region status History (S) Not Lower course of rivers. Widely spread in Indo- Utica gracilipes None (crab) FR assessed Pacific Ptychognathus Not None (crab) FR Lower course of rivers. Found in Indo-West Pacific riedelilii assessed Estuarine/brackish waters/lower region of rivers. Caridina Least Found in Madagascar, Mascarene Islands, Samoa Ninja shrimp EM serratirostris concern Vanuatu, N. Caledonia, Futuna, and French Polynesia Not Mainly marine environments sometimes in lower Palaemon debilis Feeble prawn EM assessed course of rivers. Widespread in the Indo-Pacific. Cave species, living in brackish waters. Found in Macrobrachium Least Cave prawn EM Christmas Island, New Ireland, Vanuatu, Samoa microps concern and New Caledonia. Macrobrachium Hawaiian river Least Lower region of rivers near estuary. Widespread in EM grandimanus prawn concern the Pacific Koua river Macrobrachium Least Lower course of rivers including estuarine zone. prawn (E), A australe concern Can climb barriers. Widespread in Indo-Pacific Oura itara (S) Macrobrachium Berit river Least A Lower course of rivers. Widespread in the Pacific bariense prawn (E) concern Macrobrachium Scissor river Least A Lower course of rivers. Widespread in the Pacific latidactylus prawn (E) concern Lower course of rivers near estuary. Reported Buehler’s Least Caridina buehleri FR from Papua New Guinea, Indonesia, Vanuatu and shrimp concern Western Samoa. Lower to mid region of rivers. Found in Least Caridina typus1 Type Shrimp FR Madagascar, Japan, Vanuatu, New Caledonia, concern Fiji, Futuna and Samoa Mid to higher regions of rivers. Found in India, Least Caridina weberi1 Weber’s shrimp FR Vietnam, Philippines, Vanuatu, New Caledonia, concern Fiji, Futuna, Samoa, Cook and French Polynesia. Lower-mid region of rivers. Found in India, Macrobrachium Noumea river Least A Vanuatu, New Caledonia, Futuna, Cook, Samoa aemulum1 prawn concern and French Polynesia Reported from the lower course of rivers1. Found Macrobrachium Lolipop prawn Least A in Taiwan, Philippines, New Caledonia, Futuna, gracilirostre1 (E) concern Samoa and Fiji. Macrobrachium Peaceful prawn Least Lower and mid regions of rivers. Widespread in A placidulum (E) concern the Pacific Atyopsis Bamboo Least Mid to higher regions of rivers. Found in Samoa, A spinipes1 shrimp concern Philippines, N.Caledonia, Vanuatu, Fiji, Futuna Low-high regions of rivers. Found in Philippines, Green lace Least Atyoida pilipes1 A French Polynesia, N.Caledonia, Vanuatu, Futuna, shrimp concern Cooks and Samoa Mountain river Macrobrachium Least Medium to high regions of rivers. Widespread in shrimp (E), A latimanus1 concern Indo-Pacific Oura onana (S) Giant jungle Macrobrachium Least Lower to high regions of rivers. Widespread in the prawn (E), A lar1 concern Indo-Pacific Oura pape (S) 1 Species recorded during the dry season survey for this project Source: EIA Volume 2 – Annex C Aquatic Biodiversity and habitat Assessment (Entura 2019)

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5.2.14 Migration requirements

258. The amphidromous species present in Samoa reproduce in rivers and hatched larvae are passively transported by the river current to the sea. Amphidromous larvae consume oceanic plankton and are physiologically adapted for development in seawater, as a consequence, larval survival depends on rapid transport to the sea (within days) to begin their larval marine feeding stage (Thuesen et al. 2011; Keith et al. 2013). Thus, slower moving rivers with large lowland and estuarine components; impoundments which create slow moving environments; or riverine flow regulation can represent impassable barriers to larval migration.

259. The requirement for rapid transport to the sea is likely to explain why the peak egg development and hatching period for gobies and crustaceans is during the wet season when generally higher flows occur and transport of larvae to the sea is likely to be most rapid. For example, a study in Reunion Island on the red-tailed goby, (Sicyopterus lagocephalus), the most abundant migratory climbing fish species present in the Vaisigano River, found the peak period for reproduction and egg hatching spanned was during the wet season from February to May (Teichert et al. 2013).

260. For red-tailed gobies, studies have reported that larvae die after seven days if they have not reached the sea (Valade 2001), while another study found significant mortality occurred if the larvae have not reached the sea after four days (Ellien et al. 2014). Data on survival time is not available for the other goby species present; however, given the similarities in general physiology and life history within gobies species it reasonable to conclude that rapid larval transport to the marine phase is a common requirement to all species.

261. Reproduction in amphidromous prawns and shrimps is also known to coincide with the wet season to facilitate the rapid downstream transport of hatched larvae (Novak et al. 2015).

262. Depending on the species, a period of weeks to months of development are spent in the marine environment before migration of juvenile gobies and crustaceans occurs back into the rivers. Increasing river flows entering the estuary are thought to provide the main cue for juvenile gobies and crustaceans to begin their upstream migration (Keith et al. 2013). In general, the migration of post-larvae gobies from the river mouth is possible all year round but seems to be concentrated from December to February (Keith et al. 2013).

263. The migratory amphidromous species present do not exhibit a homing behaviour that sees adults returning to their natal streams. Rather, at the end of their marine phase post-larvae/juveniles are attracted to the nearest freshwater inflow which may be a long distance from the river they were hatched in depending on the where they have been transported to by the coastal currents.

264. Eels have a catadromous life history, migrating downstream as adults to spawn in the open ocean and juveniles migrate back to the estuaries to begin their upstream migration. Anguilla marmoratus, by far the most abundant eel species recorded in the Vaisigano River, begin their upstream migration between October and April with a peak in numbers in January and February (Keith et al. 2013). The trigger for upstream migration is not completely understood but is thought to be linked to lunar cycles.

265. Returning juveniles of amphidromous gobies and catadromous eels are able to migrate upstream past significant barriers providing there is a continual film of water running down the obstacle (Keith et al. 2015). Migratory amphidromous prawns and shrimps are also capable of climbing up or around cascades, low vertical walls and dams, as well as taller dams as long as there is an inclined surface with a suitable downstream water flow (Hayashi and Hamano, 1984; Holmquist et al., 1998; March et al., 2003).

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Table 5.11: Fish species recorded in 2013

Downstream Samasoni Samasoni Alaoa East Alaoa West Fale ole Fee power station intake Intake Intake Fish species intake (East (main (middle (middle-east (middle branch) branch, lower branch) branch) branch) river) Anguilla marmorata x x Schismatogobius sp.1 x Stiphodon hydoreibatus x x x Stiphodon elegans x Sicyopterus lagocephalus x x x x Sicyopterus pugnans x Glossogobius Celebius1 x Psammogobius biocellatus x Eleotris fusca x Kuhlia salelea x Liza vaigiensis x Total fish species 7 3 3 0 3

1 This record requires confirmation as do not match the current taxonomy guide for Samoan Fish (Keith et al. 2013) Source: ADB & Atherton et al – Initial Environmental Examination for Samoa Renewable Energy Project (2013)

Table 5.12: Crustacean species recorded in 2013

Crustacean species Downstream Samasoni Alaoa East Alaoa West Fale ole Fee Samasoni intake (middle Intake Intake (middle intake (East Power station branch) (middle-east branch) branch) (main branch, branch) lower river) Atyoida pilipes x x x Atyopsis spinipes x

Caridina serratirostris x Caridina weberi x x x x

Macrobrachium australe x

Macrobrachium gracilirostre x x

Macrobrachium grandimanus Macrobrachium lar x x x

Macrobrachium Latimanus x Total crustacean species 1 3 5 3 4

Source: ADB & Atherton et al – Initial Environmental Examination for Samoa Renewable Energy Project (2013)

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5.2.15 Priority biodiversity: natural and critical habitat

266. A natural and critical habitat assessment was carried out for the project (Volume 2 - Annex K, Appendix A) and has identified the landscape within which the Project is situated is likely to be or is actual critical habitat for: one globally critically endangered and one endangered bird; two endangered lizards; three least concern, one data deficient and one not evaluated fish species; an endangered snail; one critically endangered and one endangered palm; and one internationally-recognized area (Table 5.13). Some uncertainty remains in the conclusions of this assessment, given limited information on the fine-scale distribution of many of these species in Upolu. Nonetheless, this uncertainty will not change the overall conclusions of this assessment. Although in some cases conclusions could be refined by further studies, on a precautionary basis the features listed in Table 5.13 are all be considered priority biodiversity for the Project to avoid, mitigate and – where necessary – offset impacts upon.

267. Following Table 5.13 are a set of brief profiles for critical habitat-qualifying biodiversity, focusing on where and when each is likely to occur in the Project area. Additional details of why each feature meets critical habitat criteria are given in Volume 2 - Annex K, Appendix A.

268. The Project is situated in a mosaic of natural and modified habitat, both terrestrial and freshwater. Remaining forest may be heavily impacted in places, particularly by the spread of invasive species, but mostly retains primary ecological functions and is of value to a number of priority species. Given the prevalence of non-native tree species which are difficult to identify from remotely sensed imagery, on a precautionary basis all forest is currently considered Natural Habitat, and non-forest areas Modified Habitat (Volume 2 - Annex K, Appendix A.3). Data on many individual species’ distributions across the area are sufficiently sparse to preclude detailed mapping of Critical Habitat. On a precautionary basis, it is therefore assumed that all terrestrial Natural Habitat, and any terrestrial Modified Habitat with remaining mature trees, may also qualify as critical habitat. Figure 5.28 summarizes the location of aquatic critical, natural and modified habitat in the Vaisigano watershed, based on Entura (2019a).

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Table 5.13: Summary of critical habitat-qualifying biodiversity in the Project area

Biodiversity Biodiversity Critical Habitat Justification Present in Project type criterion qualified Project impacts? 1 2 3 4 5 6 impact area? Bird Tooth-billed Pigeon X Terrestrial Area of Assessment (AOA) supports more than 0.5% of the Likely Likely Didunculus population, and five pairs, of this globally CR bird. (seasonally) strigirostris Bird Mao Gymnomyza X Found during Project baseline surveys, including indications of breeding Yes Yes samoensis in/near the Project site. Terrestrial AOA supports more than 0.5% of the population, and five pairs, of this globally EN bird. Reptile Olive Small-scaled X On a precautionary basis, it is possible that the terrestrial AOA holds more Possibly Potentially Skink Emoia lawesi than 0.5% of the global population of this globally EN lizard. Reptile Samoa Skink X On a precautionary basis, it is possible that the terrestrial AOA holds more Possibly Potentially Emoia samoensis than 0.5% of the global population of this globally EN lizard. Fish Schismatogobius X X The aquatic AOA is likely to hold more than 1%, and possibly 10%, of this Yes Potentially tuimanua recently described restricted-range fish (not yet evaluated - IUCN Red (downstream) List). Fish Fat-snout Goby X On a precautionary basis, it is possible that the aquatic AOA holds more Yes Yes (Sicyopterus than 1% of the global population of this globally LC fish. pugnans) Fish Stenogobius X On a precautionary basis, it is possible that the aquatic AOA holds more Yes Potentially genivittatus than 1% of the global population of this globally Least Concern fish. (downstream) Fish Green Riffle Goby X On a precautionary basis, it is possible that the aquatic AOA holds more Yes Yes (Stiphodon than 1% of the global population of this globally LC fish. elegans) Fish Stiphodon X On a precautionary basis, it is possible that the aquatic AOA holds more Yes Yes hydroreibatus than 1% of the global population of this globally DD fish. Snail Thaumatodon X On a precautionary basis, it is possible that the terrestrial AOA holds more Possibly Unlikely hystricelloides than 0.5% of the global population of this globally EN snail. Plant Drymophloeus X On a precautionary basis, it is possible that the terrestrial AOA holds more Possibly Unlikely samoensis than 0.5% of the global population of this globally CR palm. Plant Clinostigma X On a precautionary basis, it is possible that the terrestrial AOA holds more Possibly Potentially samoense than 0.5% of the global population of this globally EN palm. Internationally Apia Catchments X Area of high biodiversity value, internationally recognized as an Important Overlapping Yes recognized Key Biodiversity Bird Area and Key Biodiversity Area. area Area Source: Volume 2 - Annex K Natural and Critical Habitat Assessment (2019)

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Figure 5.28: Schematic of aquatic area of analysis, showing areas of critical, natural and modified habitat, and any critical habitat-qualifying fish species present in each stretch

Source: Volume 2 - Annex K Natural and Critical Habitat Assessment (2019)

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269. Natural habitat. All Terrestrial Natural Habitat is precautionarily treated as Critical Habitat, in the absence of detailed information on the distribution of key species. As a result, impacts on terrestrial Natural Habitat are currently considered to be the same as those on Critical Habitat.

270. Critical habitat. Critical habitat is defined by ADB for purposes of informing investment decisions as a subset of both natural and modified habitat that deserves particular attention. Critical habitat includes areas with high biodiversity value, including habitat required for the survival of critically endangered or endangered species; areas having special significance for endemic or restricted-range species; sites that are critical for the survival of migratory species; areas supporting globally significant concentrations or numbers of individuals of congregatory species; areas with unique assemblages of species or that are associated with key evolutionary processes or provide key ecosystem services; and areas having biodiversity of significant social, economic, or cultural importance to local communities (ADB, 2009).

271. Critical habitats include those areas either legally protected or officially proposed for protection, such as areas that meet the criteria of the World Conservation Union classification, the Ramsar List of Wetlands of International Importance, and the United Nations Educational, Scientific, and Cultural Organization’s world natural heritage sites (ADB, 2009).

272. ADB Safeguard Policy Statement (SPS) requirements, state that project activities should not be implemented in areas of critical habitats, unless (i) there are no measurable adverse impacts on the critical habitat that could impair its ability to function, (ii) there is no reduction in the population of any recognized endangered or critically endangered species, and (iii) any lesser impacts are mitigated. If a project is located within a legally protected area, implement additional programs to promote and enhance the conservation aims of the protected area. In an area of natural habitats, there must be no significant conversion or degradation, unless (i) alternatives are not available, (ii) the overall benefits from the project substantially outweigh the environmental costs, and (iii) any conversion or degradation is appropriately mitigated. Use a precautionary approach to the use, development, and management of renewable natural resources (ADB 2009).

273. The project area is contained within the Apia Catchments KBA. A KBA is a site of critical importance for the conservation of globally important biodiversity (Conservation International et al., 2010). KBAs support the regular occurrence of one or more globally threatened species. The Apia KBA totals 8,335 hectares and includes the mid to high elevation portions of catchments that drain to Apia, including the Vaisigano River. There are eight globally or nationally threatened species found within this KBA: Samoan bush palm, manumea or toothbilled pigeon, ground dove, mao or Mao mao, Samoan broadbill (Myiagra albiventris), Samoan triller (Lalage sharpie), Samoan flying fox (Pteropus samoensis) and the land snail (Thaumatodon hystrucelloides).

274. The closest legally protected area is Mount Vaea Scenic Reserve, located on the summit of Mount Vaea approximately three kilometres to the north. This area includes the Stevenson Memorial Reserve which is the burial ground of author Robert Louis Stevenson. The O le Pupu Pue National Park is located approximately five kilometres to the south-east and is immediately adjacent to the Vaisigano catchment. The footprint is located on the edge of the Apia Catchment KBA (Birdlife 2019). However, the KBA site has no legal protection.

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5.3 Environmental Flow

5.3.1 Current hydropower development in the Vaisigano River catchment

275. Currently, there are three hydro-power schemes in the catchment which affects flow in the main branch and in three branches of the Vaisigano River (east, middle east and west) while the fourth (western branch) is largely unregulated for the majority of its course15 and enters the main stream a short distance upstream of Samasoni Weir (Figure 5.29).

276. At least six species of climbing migratory fish and seven species of migratory crustaceans inhabit the river (Entura 2019). The climbing migratory fish species are the only fish species which naturally occur upstream of the lower reaches of the river as significant waterfalls are an unpassable barrier to the non- climbing fish species which occur in the lower reaches. All of the migratory species must move between the freshwater and marine environments to complete their life cycles.

277. Water movement influenced by the three hydro schemes is described below and can be visualised in the schematic; site photos and flow duration curves (Entura 2019).

278. Fale ole Fee scheme. The Fale ole Fee Scheme takes water from the upper section of the east branch (Figure 5.29Error! Reference source not found.). No or minimal environmental flow is released below the offtake weir and thus this 5.5 km section is severely flow depleted or dry for long periods (Volume 2 - Annex D, Entura 2019). The frequent lack of flow connectivity to the lower reaches of the river and the ocean has resulted in a low abundance and diversity of fish fauna because of reduced opportunities to migrate upstream from the main branch of the river. Water from the Fale ole Fee scheme re-enters the main channel a short distance upstream from the Samasoni Weir (Figure 5.29).

279. Hydrology modelling indicates the channel below the offtake weir does not flow for approximately 40 percent of the year ((Volume 2 - Annex D, Entura 2019). Annual median flows are four times lower under the current than natural flow regime. The annual high flow regime is also substantially reduced under the current flow regime, but peak annual flows are only moderately affected as peak flows are well in excess of the capacity of the offtake (Volume 2 - Annex D, Entura 2019).

280. Seasonally, the largest impacts occur during the dry season where the offtake takes the majority of the flow such that the channel below the weir is dry for approximately 73 percent of the time in August, 90 percent of the time in September, October and November and for 60 percent of the time at the start of the wet season in December ((Volume 2 - Annex D, Entura 2019).

281. Field observations indicate that tributary pick up is limited below the Fale ole Fee offtake as no flow was observed in the east branch channel during field surveys in July and September 2018 and in April 2019 ((Volume 2 - Annex D, Entura 2019).

282. The scheme discharges water back into the main branch of the Vaisigano River downstream from the where the existing Alaoa Scheme discharges water back into the main branch and upstream from the influence of the Samasoni Scheme (Figure 5.29). The return of water from the Alaoa and Fale ole Fee schemes returns the current flow regime to that similar to natural (Annex D - Entura 2019).

15 The middle branch of the river is regulated and enters the final reach of the larger western branch, which results in lower flows in the last 300 metres of the western branch.

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Figure 5.29: Existing hydro-power infrastructure and issues in the Vaisigano River catchment

Apia Harbour Key Unregulated flow Minor flow ateration The lower reaches of the river have the Moderate to high flow alteration greatest fish diversity, but a short distance Severe flow depletion upstream Samasoni PS, falls prevent the Hydro-scheme canal/pipeline upstream movement of aqautic species Samasoni PS Hydro-scheme penstock which cannot climb Tailrace FOF Power scheme

Alaoa Power scheme Samasoni Power scheme

Habitat in 4.5 km reach significantly degraded

pipeline by absence of flow for much of the year, which

also reduces opportunities for migratory main branch main Flow direction Flow species to pass Samasoni Weir. An

Samasoni environmental flow is needed to provide permanent aquatic habitat through this reach and to improve migration past Samasoni Weir.

Samasoni headpond Samasoni Weir FOF PS Alaoa headpond middle branch weir Alaoa PS

The western branch is unregulated but would benefit through increased migragition of fish and crustaceans if an environmental flow was released over Samoasoni Weir. Migration of fish into the middle branch is currently compromised by the offtake for the Alaoa Migratory fish and crustaceans can currently Headpond, and would benefit from an migrate into the middle-east and east branches environmental flow over its offtake weir and Alaoa weir although there are limited opportunities for from an environmental flow over Samasoni migration into the east branch due to flow Weir extraction for the FOF scheme and long periods of zero flow below the FOF weir. Flow is less regulated in the middle-east branch and the diversity and abundane of migratory species is higher as a result

middle branchmiddle FOF weir western branch western

middle eastbranch middle Source: Alaoa Dam Project: aquatic ecology report and e-flow report – Entura (2019)

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283. Alaoa scheme. The Alaoa scheme takes water from the middle-east branch approximately 2.5 kilometres upstream from where the middle-east and east branches join (Figure 5.29). Flow modelling indicates that during the dryer months the canal frequently diverts all the flow with zero flow modelled for the majority of August to December (Volume 2 - Annex D, Entura 2019).

284. However, in contrast to the east branch downstream the FOF offtake (Volume 2 - Annex D, Entura 2019), there is more tributary pickup below the Alaoa offtake. For example, during the aquatic ecology survey at the height of the dry season in September 2019, the weir on the middle-east branch offtake was observed to be just spilling but inflows had returned additional flow to the channel 500 metres downstream from the offtake (Volume 2 - Annex D, Entura 2019).

285. Additionally, hydrology modelling approximately 2 kilometres downstream to where the middle-east branch enters the proposed inundation zone for the Project indicates permanent flow in all months even though the magnitude of all flow elements, other than peak flows, is reduced compared to the flow regime prior to regulation (Volume 2 - Annex D, Entura 2019).

286. Downstream of Alaoa power station tailrace. The water diverted from the Alaoa offtake flows along the Alaoa Canal to the Alaoa Headpond and then enters the penstock into the Alaoa Power Station where the tailrace discharges back into the main channel approximately 500 metres downstream from where the middle-east and east branches join (Error! Reference source not found.).

287. Flow modelling indicates that the current flow regime is similar to the natural flow regime immediately downstream where the Alaoa Power Station discharges the scheme water back into the main channel (Entura 2019). The small reduction in flow magnitude is due to the abstraction of water upstream for the FOF scheme which returns water to the main channel a short distance further downstream (Entura 2019). Site photos are provided in (Volume 2 - Annex D, Entura 2019).

288. Middle branch offtake. The Alaoa scheme also takes water from the lower course of the middle branch diverting flow via a canal into the Alaoa Headpond (Figure 5.29). Hydrology modelling indicates that the middle branch is dry below the offtake weir for the majority of the year (57 percent of the time on average), particularly from August to December when modelled spill occurs 2-18 percent of the time (Annex D, (Entura 2019). Site photos are provided in Annex D, (Entura 2019)

289. Samasoni scheme. The Samasoni Scheme is the largest of the three existing power schemes in the catchment. The Scheme diverts water from the main branch of the river (combined east, middle-east, middle and west branches) into the Samasoni Headpond (Figure 5.29). The scheme has a 2.58 m3/s capacity (meaning all flow up to 2.58 m3/s is diverted into the Samasoni pipeline) and for extended periods no flow spills back into the river over Samasoni weir resulting in a dry channel for approximately 4.2 kilometres until water from the Samasoni Scheme is discharged back into the channel from the power station tailrace. Site photos are provided in Annex D, (Entura 2019).

290. Downstream Samasoni weir to Samasoni power station. This is a 4.2km channel section. The results of hydrology modelling indicate that there is zero spill over Samasoni Weir for the majority of the time from July to January, and in most months, spill occurs for less than ten percent of the time (Volume 2 - Annex D, Entura 2019). A more permanent spill occurs from February to June, but periods of zero flow still occur, particularly in May and June where the modelling indicates zero spill for 20 and 40 percent of the time respectively (Volume 2 - Annex D, Entura 2019).

291. The catchment map and hydrological modelling indicates that there are tributary inflows in the 4.2 kilometres between Samasoni Weir and Samasoni Power Station. The hydrological model uses the known flow record from the East Alaoa gauging station to scale the inflow contribution from these tributaries. However, field observations during the dry and wet season indicate that contribution of these tributaries is exaggerated in the modelling.

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292. For example, field observations in the dry season (September 2018) recorded zero flow for the 4.2 kilometres downstream Samasoni Weir to Samasoni Power Station, observations which appears to be common for the dry season according to local anecdotal information. During the wetter months, spring inflows return a small flow to main channel approximately 3.2 kilometres downstream Samasoni Weir, but the channel upstream of this spring inflow appears to be dry for at least a portion of the year (field observations in July 2018, February 2019 and May 2019), a situation which is also common according to local information.

293. There is no data or information on the tributaries downstream Samasoni Weir which can be used to apply different rules to the hydrological modelling to more accurately model the contribution of tributaries downstream Samasoni Weir. Therefore, this assessment assumes the modelling immediately downstream Samasoni Weir reflects the flow regime in the reaches further downstream for extended periods of the year, particularly in the dry season

294. Discussion of the changes to the hydrology at this location during operation of the new scheme is provided in Section 5.1.5.

295. Downstream of Samasoni power station. Samasoni Power Station tailrace returns up to 2.58 m3/s to the river and below this point the flow regime returns close to that prior to regulation (Annex D, (Entura 2019).

5.3.2 Changes in flow with the new flood protection dam

296. The new flood protection dam will have no influence on the operation of existing Alaoa or Fale ole Fee power schemes which divert water upstream from the new dam. Therefore, flow in the east, middle- (Entura 2019) or middle branches located upstream of the proposed dam will remain as current during operation of the Project. During operation of the new scheme, there will be a large new instream dam across the river a short distance downstream from the junction of the middle-east and east branches. Water movement influenced by the new scheme is described below and can be visualised in the schematic (Error! R eference source not found.) and flow duration curves (Volume 2 - Annex D, Entura 2019).

297. The main purpose of the dam is flood protection. The dam wall is 60m-high, but the storage level will typically be approximately 26 metres below full supply level (FSL) to retain the capacity to store large inflows and prevent flooding downstream. The new power scheme is small (1 m3/s maximum discharge) but increases the financial viability of the overall scheme and boosts the renewable energy supply to Samoa which currently relies heavily on diesel electricity generation.

298. New dam and power station to existing Alaoa power station. A penstock will exit the new dam wall and supply the new power at the base of the dam wall.16 The scheme will mostly operate as a run of river up to the station limit (1 m3/s), with inflows into the storage equalling inflow to the power station. The power station will discharge water back into the main branch of the river. In addition to the power station flow, the dam has a mid-level dewatering valve with a 3 m3/s capacity and emergency dewatering valve at the base of the dam with a 50 m3/s capacity. The mid-level outlet will be used to lower the dam level more rapidly when peak inflows are occurring to reduce the chance of dam spill. The dam will only spill during events that are greater than a 1 in 150-year event. For example, the hydrological modelling record reported just three spill events in the 48 years modelled.

16 Based on recommendations of the EIA study, the location of the powerhouse has been relocated from 250m from the dam wall to the toe of the dam to ensure there is no de-watered section.

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Figure 5.30: Existing hydro-power infrastructure with proposed new dam and issues in the Vaisigano River catchment

Key Apia Harbour Unregulated flow Minor flow ateration The lower reaches of the river have the Moderate to high flow alteration greatest fish diversity, but a short Severe flow depletion Hydro-scheme canal/pipeline distance upstream Samasoni PS, falls Hydro-scheme penstock prevent the upstream movement of Tailrace aqautic species which cannot climb Samasoni PS FOF Power scheme

Alaoa Power scheme Samasoni Power scheme Proposed New Power scheme

Habitat in 4.5 km reach significantly degraded

pipeline by absence of flow for much of the year, which also reduces opportunities for migratory

species to pass Samasoni Weir. An main branch main Flow direction Flow environmental flow is needed to provide Samasoni permanent aquatic habitat through this reach and to improve migration past Samasoni Weir.

Samasoni headpond Samasoni Weir FOF PS Alaoa headpond Alaoa PS New PS

New Dam Weir

The western branch is unregulated but would benefit through increased migragition of fish and crustaceans if an environmental flow was released over Samoasoni Weir. Migration of fish into the middle branch is currently compromised by the offtake Migratory fish and crustaceans will no for the Alaoa Headpond, and would longer be able to migrate up into the benefit from an environmental flow Alaoa weir middle and east branches due to the dam over its offtake weir and from an wall barrier. Migration into the east environmental flow over Samasoni branch is already severly compromised by Weir. the absence of flow below the FOF for long periods of the year

middle branchmiddle FOF weir

western branch western middle eastbranch middle

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299. The emergency dewatering valve is not anticipated to be used during general operation but is present as part of the dam safety design. It is not recommended that the emergency dewatering valve is used to deliver higher flows for environmental water releases as this could risk release of large quantities of highly turbid water entrained from the sediments which will accumulate at the bottom of the dam (Gippel 2019).

300. The new power station will operate annually for just of 80 percent of the time, but operation varies seasonally (Volume 2 - Annex D, Entura 2019). From January to June the baseflow, median and fresh flow regime is similar to current although cease to flow events are modelled to occur for approximately eight percent of the time in January under the new scheme which are modelled to never occur under the current flow regime (Volume 2 - Annex D, Entura 2019). From July to December, operation of the new scheme elevates the flow regime for much of the time compared to current but there are also periods when the flow stops due to the power station ceasing to operate in the dry months when inflows to the reservoir are low and the storage level is low (Annex D, (Entura 2019)). Cease to flow events are most common from August to December to with zero flow occurring from approximately 30 to 50 percent of the time (Volume 2 - Annex D, Entura 2019).

301. The mid-level outlet operates most frequently from February to May, providing flow for approximately 75, 88 and 85 percent of the time in these months respectively (Entura 2019). However, from July to December, the mid-level outlet is in operation 20 percent of the time or less, particularly from August to November where it operates less than five percent of the time (Volume 2 - Annex D, Entura 2019).

302. Alaoa power station to immediately upstream Samasoni weir. This section is a 1km reach. This location describes the flow downstream the existing Alaoa Power Station until where the western branch and Fale ole Fee Scheme water have joined the main branch a short distance upstream from Samasoni Weir.

303. The tailrace of the existing Alaoa Power Station returns flow to the main channel in all months (Volume 2 - Annex D, Entura 2019). Annual peak flows are reduced due to the new dam capturing high inflows (Volume 2 - Annex D, Entura 2019). The annual high flow regime is elevated due to the combination of power station outflows (from here and the new station upstream) and mid-level outlet releases. The magnitude of annual fresh, median and elevated baseflows are similar to current.

304. Low baseflows are reduced compared to current due to regulation from the dam and operation of the new power station upstream which ceases to operate when inflows to the storage are low and coinciding with low storage levels in the dry season. During these periods, the storage level will be maintained to prioritise water availability for the water treatment plant.

305. Aside from lower peak flows the monthly flow regime during operation of the scheme is similar to current from February to June (Volume 2 - Annex D, Entura 2019). From July to January the magnitude of median and elevated baseflows are similar to current but low baseflows are lower due to a reduction or cessation of operation of the new power station for the reasons described above, particularly from August to November (Volume 2 - Annex D, Entura 2019). From August to November the influence of inflows from the new scheme upstream slightly elevates the magnitude of high and fresh flows compared to current as the power station is running at maximum in order to draw the reservoir level down to create storage capacity for the next wet season.

306. Immediately upstream of Samasoni weir. In the final reach of the river before water is diverted into the Samasoni Power Scheme, the existing Alaoa, Fale ole Fee and new power scheme have returned diverted water back to the main channel and the unregulated western branch has also entered (Figure 5.29). The effects of the new dam on the flow regime are less apparent at this location with the flow regime similar to the current and natural flow regime other than peak flows which are reduced during operation of the new scheme (Volume 2 - Annex D, Entura 2019). There is also a small elevation of high and fresh magnitude flows in most months which is caused by the operation of the new power scheme and the mid-level dam releases.

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307. Downstream of Samasoni weir to Samasoni power station. As discussed, operation of the scheme results in lower peak flows compared to current (Volume 2 - Annex D, Entura 2019). This is particularly prominent in the wet season where modelled peak monthly flows range from 84 m3/s to 1050 m3/s under the current flow regime but are a third to half lower under the scheme flow regime due to the new dam capturing flood flows (Entura 2019). Peak flows are less than 20 m3/s during the dry season and are reduced by 25 to 35 percent during the scheme compared to current (Volume 2 - Annex D, Entura 2019).

308. The remaining elements of the flow regime are similar during the scheme to the current situation. The hydrology modelling indicates that there is zero spill over Samasoni Weir for the majority of the time from July to January, and in most months spill occurs for less than ten percent of the time (Annex D, Entura 2019). A more permanent spill occurs from February to June, but periods of zero flow still occur, particularly in May and June where the modelling indicates zero spill for 20 and 40 percent of the time respectively (Volume 2 - Annex D, Entura 2019).

309. As discussed, immediately upstream of Samasoni Weir, where flow occurs perennially, operation of the new power scheme and the mid-level dam outlet results in an increase in magnitude of high and fresh flows in some months compared to current. Immediately downstream from the weir, the proposed scheme results in a small increase in the duration of spill events (Volume 2 - Annex D, Entura 2019).

310. A more detailed analysis of spill events at this location is provided in Volume 2 - Annex D, Entura 2019.

311. Downstream Samasoni power station to Apia Bay. Over this 1 km reach the project reduces peak flows in similar magnitude to that described for the river directly downstream Samasoni Weir (Volume 2 - Annex D, Entura 2019). The remaining elements of the flow regime are similar during the scheme to the current and natural scenarios (Volume 2 - Annex D, Entura 2019).

5.4 Socio-economic Environment

312. This section presents an overview of the socio-economic situation across Samoa. Detailed consideration of socio-economic and land tenure issues are developed in a stand-alone document, refer to EIA Volume 2 - Annex G Land Acquisition and Resettlement Plan.

5.4.1 Population and demography

313. Demography. Overall 92% of the population are Samoan, 7% are people with mixed European and Polynesian ancestors, about 0.4% of the population is European. Religion is strong in Samoan culture; 32% of Samoans belong to Christian Congregational Church of Samoa, 19% are Roman Catholic, 15% are Mormon, 4% are Seventh-Day Adventist, 5.5% other Christian, and 2.4% are other while less than 1% of the population state they are not religious.

314. Of the total population, 20% lives in Apia urban area, a third lives in north-west Upolu and 23% live across the rest of Upolu. The remaining 24% live on Savai’i. Figure 5.31 shows population distribution across Upolu. Five districts, including Apia urban area where the port is located, are the most populous with between 7,731 and 24,105 people.

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Figure 5.31: Population distribution on Upolu

Key to population distribution:

Source: SBS - Socio-economic Atlas (2012)

315. Across Samoa, the average population density is 69 people/km2 and average household size is 7- 8 people. Four districts, including Apia urban area, have the highest population density of 308-584 people/km2 (Figure 5.32).

Figure 5.32: Population density on Upolu

Key to population density:

Source: SBS - Socio-economic Atlas (2012)

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316. Village administration. Over 98% of the villages are traditional i.e. governed by the Fono (council of chiefs). A traditional village has a recognized traditional salutation (fa’alupega) and typically consists of a number of extended families each headed by a matai (chief), and each extended family comprises a number of households living often in a cluster of houses on extended family land.

317. About 14% of Samoan population 15 years and older have matai (chief) title from their village of residence. The island of Savai’i has the most districts with 18% or more people 15 years and older with matai title. On Upolu only one district records 18-21% of the population with matai title, eight districts record 15-17% of the population with matai title and 15 of the districts record up to 14% of the population with matai title.

318. Traditional village organization consist of three main bodies (i) the Fono comprising all matai title holders; (ii) aumaga (untitled men); and (iii) aualuma ma tamaita’i often referred to as the women’s committee. Each organization has well defined functions and responsibilities. The Fono makes bylaws and adjudicates on matters of law and order and ensures the proper allocation and use of communal resources especially village owned lands.

319. The aumaga generally serve the needs of the Fono, enforce Fono decisions and are responsible for implementing the physically demanding community activities including cultivation and fishing. The aualuma ma tamaita’i has responsibility for health and hygiene-related matters, but their more important traditional role is as weavers of highly valued fine mats (toga) that are the main currency of value for exchange at occasions including weddings, funerals and the bestowing of chiefly titles.

5.4.2 Communities in the project area

320. The proposed project is to be carried out on a large piece of undeveloped government land amounting to approximately 1,851 hectares that covers the entire middle and upper watershed of the Vaisigano River. The project site is accessible only on foot at a distance of about 1.0 km from the nearest unpaved road. No one lives in or adjacent to the project area.

321. Upper Magiagi sub-village—variously called Talaloa, Aukilani, or simply upper Magiagi sub- village—consists of about two dozen semi-rural households strung out along a public road that runs along the ridge line to the east of and high above the project site. The only ready access from upper Magiagi sub- village to the project site is either from the south walking 1,000m up the river valley from the unpaved portion of Alaoa Road or from the east walking a rough and steep trail of about 500m in length from the upper Magiagi Road. The higher reaches of the valley are too steep and remote to provide direct access to the project site or to the land above (south of) the proposed dam site.

322. Lower Magiagi sub-village—often called Ueligitone—is a somewhat larger community that lies directly on the river’s floodplain. It is semi-rural at its southern end (2.25 km north of the project site) and semi-urban at its northern end (3.7 km north of the project site). Both upper and lower Magiagi are socio- politically part of Magiagi village—the centre of which lies north northeast over 4.0 km from the dam site.

323. Alaoa is an urban residential community of about three dozen households sitting along Alaoa Road at a distance of 1.75 km to 2.0 km north northwest of the project site. Alaoa is socio-politically a sub-village of Vailima village to the south.

324. The project area is not in Magiagi or Alaoa, no land will be taken for project purposes in Magiagi or Alaoa, and no persons will be physically displaced from or relocated to Magiagi or Alaoa.

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5.4.3 Livelihoods and Employment

325. Economy. Samoa’s economy is dominated by subsistence agriculture and related activities, which support around three-quarters of the total population, including almost the entire rural population. The economy is also dominated by external aid and by remittances from Samoans residing and working abroad. The communications sector made up 4% of Samoa’s gross domestic product in 2013.

326. Labor force and unemployment. The employed population comprises people 15 years and older working as employees, employers, self-employed, street vendors and subsistence workers; it should be noted the high employment rate (94%) in Samoa is due to the large number of people in rural areas engaged in the subsistence economy. The total working age population comprises 68% who reached secondary level education, 15.2% primary and 2.8% without formal education. The unemployed population are people 15 years and older actively seeking jobs. The national unemployment rate is 5.7% (male 5.2 and female 6.8%), Apia urban area has an unemployment rate of 5.7% (male 6.3% and female 4.6%) and north-west Upolu has an unemployment rate of 6.7% (male 6.6% and female 6.9%).

327. The non-economically active population are those attending schools, performing unpaid domestic duties, and those who are not capable of working; the national rate is 59%. The labor force participation rate is the proportion of working age population (15 years and older) who are economically active in the production of goods and services. The national labor force participation rate is 41%.

5.4.4 Overview of land use and land ownership

328. Land use. The landscape on Upolu and Savai’i generally consists of a narrow coastal plain, with rocky, rugged, volcanic terrains making up the inner parts of the islands5. The vegetation in these areas is primarily composed of lowland and montane rain forests, with small areas of riverine, swamp, mangrove, and beach forest. The islands have undergone extensive deforestation, as a consequence of timber operations and clearance of land for agriculture. A large proportion of the lowland forest on Savai’i and Upolu has been cleared or highly modified, but the montane forests are less disturbed and have a rich variety of endemic flora and fauna. In the rural communities, land remains primarily under customary ownership and a large proportion of it is currently under cultivation.

329. Land use capability assessments in 1990 categorised Samoa’s land into four main classes:

1. Land with few limitations for agricultural use (39,600 ha);

2. Land with moderate limitations for agricultural use and few limitations for forestry use

3. Land with severe limitations for agricultural use and moderate to severe limitations for forestry use (59,400 ha); and

4. Land unsuitable for agricultural or forestry use (69,000 ha).

330. The predominant land use, apart from indigenous forests, is agriculture. A common land use pattern in most villages consists of a residential area with a village common ground or malae on about a kilometre- wide strip of land along the coastline. Immediately inland is a mixed cropping zone of fruit trees, bananas and coconuts, and further inland is a zone of primary food crops of taro, taamu and yams.

331. Land ownership. There are four types of land ownership in Samoa with over 80 per cent of total land under customary ownership. The rest is divided between freehold, Government, and land vested in Samoa Trust Estates Corporation (STEC) and Samoa Land Corporation (SLC). About 15% of land in Samoa is publicly owned and is generally known and recognized as Government land. Under statutory law, access to Government land is through lease or exchange of either freehold land or customary land. Freehold land takes up 4% of the total land area.

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332. Landowners independently manage their own lands which can be alienated in any manner desired by the owner, be it through sale, gifting, leasing, licensing or exchange. However, alienation to no citizens or overseas residents is prohibited under the Alienation of Freehold Land Act 1972 unless granted consent by the Head of State. Customary land vested in accordance with Samoan custom and usage, are primarily managed by the matai who is the head of an extended family.

333. As trustee for his/her family, the matai is responsible for the management and allocation of the land for various uses by family members. These lands are protected from alienation by sale by the Constitution of the Independent State of Samoa 1960, except by way of lease or license in accordance with the Alienation of Customary Land Act 1965. An emerging form of land tenure is leased land, which is land under lease arrangements between the leasor (landowner) and the leasee (applicant). All types of land, whether Government, freehold or customary, can be leased out to individuals, corporations and community or to private investors. In this regard, leasing can provide a viable option to access the land necessary for private sector growth. Ideally, leasing allows the use of land without alienating it from traditional landowners.

334. The Government closely controls the leasing of customary land. The Minister of MNRE, as the trustee of customary lands, is vested with the power to manage and administer lease arrangements between the leasor and the leasee. The Minister’s involvement in land leasing is designed to ensure that landowners are protected from entering into inappropriate land deals or making unwise decisions, and to prevent alienation of customary land or ownership from the landowner.

5.4.5 Land tenure in the project area

335. Land ownership and acquisition. No permanent land acquisition of any kind (voluntary or involuntary) is expected under the current project scope and design. All project works that fall under the scope of Entura’s feasibility study are located on government (public) land. Nearly all project works lie within a single piece of government land totalling 4,573.9 acres (1,851.0 hectares) that covers substantially all of the middle and upper Vaisigano River watershed. A small part of one access road on the west edge of the project area lies on an adjacent parcel of government land. Alaoa Road, which will serve as the access road from Cross Island Road to the construction site.

336. The New Zealand colonial Administrator of the Territory of Western Samoa acquired the Vaisigano watershed land in 1921 under Ordinance No. 18 (Land for Water Supply Purposes) with the advice and consent of the Legislative Council of the Territory. A photo of the original 1921 Ordinance map appears in Plate 5.3. The ordinance explicitly states that the land acquisition was for the purpose of protecting the watershed for use as a source of drinking water for Apia and for hydro-electric development—both of which were developed shortly thereafter.

337. EPC sought guidance from in-house counsel at the MNRE regarding the legal status of the government’s claim to the 1921 land. The resulting legal advice confirmed that there is no reason to doubt that government owns the property.17

338. Neither the New Zealand colonial government nor the modern government has forcibly excluded people of nearby villages from the acquired property. This was not initially an issue because the population of Samoa had just collapsed to its nadir in 1918 when over 20 percent of the population died in only a few weeks as a result of the Spanish influenza pandemic. Encroachment on the 1921 Ordinance land is a modest issue today, however, and presents a modest involuntary resettlement issue for the project in the form of economic displacement of 17 planters and their families (total approximately 144 adults and children). As a result, the project is determined as category B for involuntary resettlement as there is no involuntary land acquisition but there will be some involuntary economic displacement.

17 Personal communication, Fonoti Perelini, 13 September 2018

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Plate 5.3: Map showing land acquired in 1921 covering entire middle & upper Vaisigano River watershed

339. Many private residences and garden plots now encroach on the 1921 government land—notably along the southeast boundary that runs along the ridge that creates the eastern edge of the Vaisigano watershed. Residents of Magiagi village began moving into this area in 1981 following the government’s development of a road and power line for the Fale o le Fe’e head pond and penstock. The area is now an informal extension of Magiagi village. Villagers call the place Talaloa (a word that indicates a faraway place where people make their plantations) or more prosaically Aukilani (Auckland) because it sits above lower Magiagi, which is called Ueligitone (Wellington).

340. Although Talaloa is partly residential now, it was initially used by Magiagi people for plantations. The present settlement has developed in the last 20 to 30 years following EPC’s construction of the penstock road and power line. Some of the houses along the ridge at Talaloa have been occupied since at least 1982, and the heights of mature coconut trees in nearby plantations show that the adjacent land has been planted for at least 40 to 50 years.

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341. Interviews with community members before, during, and after the inventory of affected crops resulted in the census of economically displaced persons, or “Affected Persons” (APs) as set out in Volume 2 - Annex G. The census of affected persons identifies 17 households (including two female heads of household) with a total of 144 members. The census of affected persons or economically displaced persons and their respective households identified 17 households/people with assets that will be affected by the Project. The census includes 16 people whose standing crops were inventoried in February 2019, but not yet compensated, plus one person who has already been compensated for crops damaged during development of a temporary access road for the geotechnical drilling equipment

5.4.6 Economy and economic infrastructure

342. Economy. Samoa’s economy is dominated by subsistence agriculture and related activities, which support around 75 per cent of the total population, including almost the entire rural population. The economy is also dominated by external aid and by remittances from Samoans residing and working abroad.

343. Samoa’s economy has suffered from tropical cyclones. The destruction of tree crops, forests and infrastructure by cyclones has affected economic performance, especially primary production, and these impacts on the environment and the people could be felt for over three years after each cyclone. More recently, Cyclone Evan struck in December 2012. Its economic impact is still unknown but could be as significant as that which resulted from the 2009 Tsunami.

344. Transport. The two main islands are well served by coastal ring roads and Upolu has three cross- island roads.

345. The completion of the current road improvement program should see all the main roads upgraded and tar-sealed. The main international port is Apia, with an inter-island ferry service operating between Mulifanua at northwest Upolu and Salelologa at southeast Savai’i. The islands were once linked by air service between Faleolo near Mulifanua on Upolu and Maota near Salelologa on Savai’i, but this air service was discontinued in 2006. Another airport is located in North-West Savai’i at Asau. The main international airport is Faleolo Airport in northwest Upolu.

346. Water supply. Historically, community water supplies from groundwater have been derived from coastal springs commonly found around the coastal villages. Groundwater is most readily available from freshwater lenses, but aquifer yields are constrained by the risk of inducing saline intrusion. With the high rainfall and virtually no drought period, the flows of such springs are sustained throughout the year. There are minor perched aquifers, held up by less permeable strata, which may be of local significance for inland springs. Despite high rainfall occurring between October and March, many parts of Samoa are devoid of perennial streams and rivers due to the high permeability of the underlying volcanics. The driest areas are found in northwest Upolu and northwest Savai’i. Rainwater is harvested and widely practiced in dryer areas of the country such as in western Savai’i. Surface water is abstracted from catchment areas of the central highlands of Upolu and south-east of Savai’i. There are 28 surface water intakes on Upolu producing an average of 42.5 million m3 of water per year and two on Savai’i (Patamea and Sili).

347. Energy. The EPC operates 22kV transmission networks on Upolu and Savai’i and is in the process of completing staged upgrades to transmission and generation infrastructure through the ADB’s Power Sector Expansion Project. While the bulk of Samoa’s existing transmission network is via overhead cable, newer sections of the network include underground cabling. Upolu currently has a combination of hydrogeneration and diesel generation as the primary source of electricity (Table 5.14).

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Table 5.14: Electricity Production by Island and source 2017-2018

Island Source kWh % Diesel 74,936,848 48.82

Hydro 42,814,365 27.89

u Solar (EPC) 2,972,343 1.94

Upol Solar (IPP) 17,818,143 11.61 Wind 134,122 0.09 Subtotal 138,675,821 90.34 Apolima Solar 9,896 0.01

Diesel 15,526,320 9.46

Solar (EPC) 291,855 0.19

Savali Solar (IPP) 4,001 0 Subtotal 14,822,176 9.66 Total 153,507,893 100

Source: EPC 36th Annual Report 2017-2018

348. The main Upolu power station, located at Tanugamanono, has been in operation since the mid- 1970s. EPC operates four run-of-river and one dam-based hydroelectric power stations with a total capacity of around 12MW. Hydro generators on Upolu generated a total of 35.248 GWh in 2010/11, representing 36% of Samoa’s total electricity. This was slightly less than typical due to the prevailing drought conditions at the time (Table 5.15).

Table 5.15: Existing hydropower capacity in Upolu

De-rated Year Station Type Number Capacity (kW) capacity Commissioned

1 2,000 2,000 Taelefaga Dam Reservoir 1992 2 2,000 2,000 1 1,850 1,700 Lalomauga Run of River 1984 2 1,850 1,600 1 950 640 Samasoni Run of River 1981 2 950 720 Fale-ole Fee Run of River 1985 1 1,600 1,400 Alaoa Run of River 1959 1 1,000 1,000 Total 12,200 11,060

Source: EPC 36th Annual Report 2017-2018

349. Under the EPC Expansion Plan, a new diesel power station has been constructed at Fiaga, in the area of Aleisa, and replace the existing Tanugamanono power station in the EPC expansion plan. The Fiaga power station consists of four new diesel engines (5.78MW each) all-generating at 11kV. Also, three existing diesel units will be relocated from Tanugamanono to Fiaga generating at 6.6kV. New transmission lines of 33kV connect Fiaga Power Station to the new Fuluasou Substation, which supplies 22kV feeders. Tanugamanono will continue to operate as a substation serving distribution feeders and terminating transmission line from five existing hydro projects. A new underground transmission cable will connect Fuluasou to Tanugamanono. There will be a total of 10 feeders fed from three major substations supplying on Upolu.

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350. The overwhelming majority of Upolu’s load is located in the Apia area, with the remainder spread out around the coastal ring and the cross-island road. Some sections of the network experience poor power quality. Savai’i’s loads are somewhat higher in the Salelologa area but are generally distributed around the island along the coastal road. Power quality problems are common at the northern end of the island near Asau, due to the distance from the power station. Savai’i load profiles are predominantly residential, with a steady daytime load of 800kW – 1MW and an evening peak of up to 3MW. All electric generation on Savai’i is currently diesel generation located at the Salelologa Power Station, which has six diesel engines, all generating at 400/415 volts. Two 22kV feeders transits and distribute electricity out to the consumers namely the Puapua Feeder that goes along the north coast and the Asau Feeder on the south coast. The peak load in Savai’i is about 2.8MW.

351. In its 2018 Annual Report (#36) the EPC states that it remains committed to increasing the diversity of its renewable energy generation sources, particularly where this will lower the costs of electricity for the people of Samoa. The focus on hydrogeneration signified by the commissioning of the refurbished Fale ole Fee and Lotosamasoni hydropower schemes in 2017 saw a marked increase in hydrogeneration as a proportion of total generation grow by 11% year during 2018 year and now represents 28% of total EPC generation, other remarkable improvement saw hydro-production increase 62% or 16.4 million kW-h year on year. The major benefit of the significant increase in renewable generation has meant that the contribution of diesel to the generation mix has reduced from 70% (2017) to 58% in 2018; representing an annual reduction in fuel costs of $4.2 million tala, reduction of 4.5 million litres of fuel and the important 18 reduction of 12,000 tonnes of CO2 gas emissions.

5.4.7 Cultural heritage and resources

352. Cultural heritage law. Currently MNRE has mandate for the implementation of the Cultural Heritage law. This law has not been revised as the Samoan Law Reform proposed to create a separate body, the Samoan Heritage Authority. Some sites show evidence of very early of human presence. For construction of the Fale ole Fee hydropower project, archaeological remains had to be removed and transplanted away from HPP site.

353. The Samoan Code of Environmental Practices (2006) requires that should any archaeological sites be discovered during any stage of gravel extraction works such work shall cease immediately and MNRE notified forthwith. On no account shall extraction work continue until authorised by MNRE. The MNRE shall arrange an evaluation of the site in association with archaeologists before making any decision as to whether or not extraction works may proceed.

354. Cultural resources survey and assessment. The Center for Samoan Studies, National University of Samoa undertook an archaeological survey of the site. (EIA Volume 2 – Annex F Archaeological Survey Report). The survey was undertaken in four stages:

• A preliminary review which included a literature search to identify any existing archaeological research in the project area, reference to Samoa’s cultural heritage policy and legislation and analysis of aerial photographs and LiDAR images to identify any possible heritage sites (such as remains of old settlements, monuments and walls).

• A field survey (18 March - 5 April 2019) of the proposed Alaoa Dam area guided by the LiDAR images, conducted with a total of 1600 person-hours. The survey methods are described in EIA Volume 2 – Annex F, Appendix 1.

18 https://www.epc.ws/images/Publications/EPC%20Annual%20Report%202017-2018_final.pdf Pg4

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• Consultation on interests expressed by one faction of the Malietoa clan in areas adjacent to the project areas are addressed in EIA Volume 2 – Annex F, Appendix 4

• Final report preparation was undertaken in consultation with the Samoa Electric Power Corporation and Entura.

355. All of the possible features identified on the LiDAR were visited and turned out to be large “tree falls” and apparent natural terracing without evidence of human modification. As much as possible, all accessible portions of the river valleys and surrounding slopes and were surveyed on foot for evidence of human modification and use (EIA Volume 2 – Annex F, Appendix 1). Numerous natural outcroppings were encountered within the river basin, but no evidence of human modification or use was found within the river basin, flood plain or proposed flooded area.

356. No archaeological features were encountered within the proposed project area and stream basins. Although some questionable examples of possible single small grinding stone were found along the river course, it is most probable that these are the result of the action of natural water caused by the associated streams rather than human-made artefacts.

357. Outside the project area, on the central ridge just to the south of the convergence of the two branches of the Eastern Vaisigano River a partial rock outline of a standard sized fale (building/house) was observed. Stones were located, placed in a way suggesting that mark graves were located in this area; indicating small graves to the northeast; one of these is larger and comprises raised stones while the other two are smaller marked with stone rings.

358. In summary, the findings of the survey are:

• There is no evidence of heritage sites in the Project area. A complete ground survey of the Project area found no evidence of heritage sites likely to be affected by the construction of the Alaoa dam. It is possible, although very unlikely, that earthworks for the construction of the dam may reveal buried heritage remains. A chance finds protocol will be included in the environmental management plan to cover this eventuality (also see item 3). • Heritage sites of minor significance were found in areas adjacent to the Project area. The adjacent areas are unlikely to be disturbed by the Project. These include portions of old small stone house platforms, stone markers possibly indicating very old grave sites, modern era (20th century) refuse (bottles, broken household implements), and a modern era stone-marked grave (tia) which may be about 50 years old. • Incidental finds or changes to Project plan. If earthworks uncover incidental finds, or if the proposed access road is substantially widened, or if other areas are modified for associated infrastructure, the Center for Samoan Studies, National University of Samoa should be requested to send a qualified archaeologist to investigate. The investigation would determine whether further excavation should be carried out to record features of potential significance to Samoa’s cultural heritage. The recommendations on the procedures to be taken in the event of incidental finds included in the report have been integrated into the EMP.

5.4.8 Ambient noise

359. A dedicated characterisation of the acoustic environment was carried out in October 2018 at the impoundment site (where the dam will be constructed) and on approach roads that may be used by construction vehicles accessing the site. The site report is presented in Volume 2 - Annex A and summarised in this subsection.

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360. The noise monitoring supports the environmental impact assessment. It identifies the current sound environment. There are two distinct elements to the monitoring:

• Monitoring at the dam site and within the impoundment – existing conditions are river and forest, with the noise environment dominated by river noise of water flowing over riffles and occasional birdsong and insect noise. This information will be used to determine the difference in ambient noise during construction and operation and the current conditions; and • Monitoring on the access roads to the site – between the site and the Port. This information will be used to determine the difference in traffic noise impact between the current conditions and during construction.

361. Dam site. Four monitoring points were identified to characterize the noise environment at the dam site and the impoundment behind where construction activities will be concentrated. The current sound environment is a forested river valley with no permanent human habitation. Historically there has been agricultural cultivation on the flood plain of the river. The current environment is dominated by noise of the river flowing over rocks and over natural weirs plus insect noise and occasional birdcalls.

Plate 5.4: Noise monitoring at the dam site Oct 2018

362. Access roads. It is assumed that material required for the construction of the dam (rock and earth) can be obtained from within the impounded are behind the dam. Therefore, external quarry sites and processing areas will not be required, so there is unlikely to be any haulage of quarry material on public roads. However, construction will require movement of plant, machinery and supplies into the camp from the Port. Therefore, the noise monitoring exercise has been extended to identify current levels of traffic noise impact to allow determination of the impact of construction traffic on the local environment. A number of monitoring points were identified along the most likely access road on the Construction site to the Port, with particular focus on sections passing schools and colleges.

363. Figure 5.33 shows the location of the sites/points selected for noise measurement.

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Figure 5.33: Location of noise monitoring sites

Source: EIA Volume 2 – Annex A – Noise Monitoring Report

364. The noise monitoring exercises suggest that ambient noise levels at the dam site are between 53.6dB(A) for the section at the dam and influenced by the river, 68.4 db(A) directly influenced by the river and 36.2db(A) for sites not influenced by the river.

365. On the access roads from Cross Island Road to the site the existing noise environment is 47.3 dB(A) at sites with low traffic use and between 57.4 dB(A) and 61.5 dB(A) on the Cross-Island Road between the site access and Port. Refer to Table 5.16.

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Table 5.16: Summary of ambient noise levels recorded on site in October 2018

Site measurement 1 Processed data 2 and 3 (over 15 minutes) Location Influencers Date Time Duration LAmax LAeq LAmin LAmax LA10 LAeq LA90 LAmin Dominated by flowing

At Dam site 23 Oct 18 15:42 18 min 58.1 54.2 53.6 56.1 54.5 54.2 54 53.6

water ite s Dominated by flowing 100m u/s 23 Oct 18 16:11 18 Min 69.4 68.4 67.7 69.4 68.7 68.4 68.1 67.7

water am am

d 20m from river 23 Oct 18 16:37 16 min 51.0 40.9 39.9 48.8 41.3 40.8 40.1 39.9 Less river influence At At West abutment 24 Oct 18 14:59 19 min 61.0 32.9 32.9 61.0 38.4 36.2 34.1 32.9 No river influence Water Treatment Grass cutting, 24 Oct 18 15.41 15 min 67.1 47.5 45.2 62.2 48.7 47.3 46.0 45.2 Plant vehicles, voices

Vailima School 24 Oct 18 16:09 15 min 81.2 53.6 38.2 81.2 65.7 53.2 43.3 38.2 Road traffic (pm) oad r Opp. Ministry of Rooster crowing in 25 Oct 18 05:59 19 min 79.4 49.3 46.8 79.4 51.5 49.3 47.2 46.8 Education suburban area Vailima School 25 Oct 18 08:40 16 min 83.5 58.6 40.1 83.5 66.7 58.6 50.5 40.1 Road traffic (am) Access Mallifou College 25 Oct 18 09:09 15 min 84.7 61.3 47.2 84.7 68.2 61.5 53.8 47.2 Road traffic (am) Port Rd 25 Oct 18 09:52 16 min 81.9 57.4 46.6 81.9 66.7 57.4 50.6 46.6 Road traffic (am)

Source: EIA Volume 2 – Annex A – Noise Monitoring Report

Notes:

1 - Site measurement summaries are generated from software provided with Sound Level Meter (SLM).

2 - Data was also post processed using excel software. The data was collected over approximately 18minute period then post-processed over a common 15- minute period.

3 - The first and last 30 seconds of data were removed from the processed data to remove any influence from operators as they moved to and from the monitor point.

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5.4.9 Traffic movements

366. To assist in the assessment process site-focused traffic counts were carried out during the sound monitoring exercises in October 2018. The objective was to determine (i) the split between into and out of town traffic movements; (ii) morning and evening split of traffic movements; and (iii) a breakdown of the types of vehicles.

367. DISCLAIMER. The traffic counts are for indicative purposes only. They were carried out at specific sites at specific times by an individual observer not as a comprehensive analysis of traffic movements in Apia. However, it is considered that for the purposes of this environmental impact assessment they offer a useful and sufficiently detailed analysis of traffic movements.

368. The traffic counts used a project specific data sheet to record: (i) direction of flow (into or out of town); and (ii) type of vehicle (broadly private or commercial). Based on the observations future surveys based on this data collection sheet would subdivide commercial and private SUVs (Hi Lux type and SUV / RUV 4wd) in this survey they were recorded as private/ car.

369. During the morning and afternoon peak, the traffic counts suggest a 65/ 35 split. In the morning 65% into Apia and in the evening 65% from Apia (Table 5.17).

370. The fleet breakdown suggests a dominance of private cars (68%). Of particular interest to this assessment are the low numbers of Heavy Good Vehicles (Less than 2% overall). Figure 5.34 presents the Apia fleet breakdown showing the dominance of cars. It is noted that this figure may be subject to modification if the car category separated commercial SUVs (i.e. 4WD Hi-lux and SUV / RUV with commercial logos) and private owned “cars”.

Figure 5.34: Breakdown of traffic types on Cross Island Road - October 2018

Traffic Breakdown from October 2018 survey Other, 4 Taxi, 48 HGV, 4 LGV, 9 Bus >30, 11 Light bus, 24

Car, 217

HGV LGV Other Bus >30 Light bus Car Taxi

Source: EIA Volume 2 – Annex A – Noise Monitoring Report

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Table 5.17: Summary of Traffic Counts on access roads in October 2018

Traffic count details Commercial Busses Private Direction Direction Duration Bus Light Location Date Start of flow HGV LGV Other Car Taxi Count % (minute) >30 bus

Vailima Primary Up 0 1 0 1 5 30 1 38 65.6 25 Oct 18 16:11 10 School Down 1 1 1 1 2 13 1 20 34.4 Vailima Primary Up 0 0 0 1 4 28 5 38 34.5 26 Oct 18 08:40 10 School Down 0 1 0 2 4 50 15 72 65.5 Malliafou Up 0 2 0 3 3 22 9 39 39.4

CrossRd Island 26 Oct 18 09:09 10 College Down 0 3 0 3 1 44 9 60 60.6

Yacht Club / Up/out 1 0 2 0 1 11 1 17 45.9 26 Oct 18 09:53 10 Port Port Down/in 2 1 1 0 1 15 1 20 54.1

East 0 0 0 0 1 1 2 4 30.8

ht Vailima Road 27 Oct 18 04:30 15 Nig West 0 0 0 0 2 3 4 9 69.2 Total Number 4 9 4 11 24 217 48 317 As % 1.3 2.8 1.3 3.5 7.6 68.4 15.1 100

Note 1 Direction of Flow. Up means away from Downtown Apia towards South side of Island. Down means towards the downtown / port.

DISCLAIMER: The traffic counts are for indicative purposes only. They were carried out at specific sites at specific times by an individual observer not as a comprehensive analysis of traffic movements in Apia.

Source: EIA Volume 2 – Annex A – Noise Monitoring Report

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6 Consultation and Information Disclosure

6.1 Overview

371. Stakeholder consultations are intended to serve six purposes:

• Information gathering and consultation for coordination and cooperation with other government agencies and other donors. • Information gathering and consultation for assessment and mitigation of environmental impacts. • Information gathering and consultation for assessment of social impacts and mitigation measures for preparation of the EIA. • Information gathering and consultation for assessment of land acquisition and resettlement impacts and associated mitigation measures. • Information gathering and consultation for assessment and mitigation of social, gender, and poverty impacts for preparation of a summary poverty reduction and social strategy and a gender action plan. • Public awareness of the project.

372. To date the consultations have focused on stakeholders and their interests relating to item to potential project-related land acquisition and resettlement impacts and associated mitigation measures, and with information disclosure, consultation, and participation processes relating to those matters. In addition, there has been a wider programme of public awareness consultations through 2018 and 2019.

373. EIA Volume 2 - Annex H Stakeholder Consultation and Participation Report presents details of the consultations held including minutes of meetings and attendance records.

6.2 Stakeholder Identification and Engagement

374. There are three broad categories of project stakeholders: government, non-government, and donor. Government stakeholders with an interest in potential project-related land acquisition and resettlement include: (i) MOF as the executing agency, (ii) three IAs (MNRE, SWA, and EPC), (iii) Land & Titles Court (LTC), (iv) Ministry of Women, Community and Social Development (MWCSD), and (v) Land Transport Authority (LTA). Development partner stakeholders include ADB and other international donors, if any. All but LTA have been consulted directly.

375. The LTC handles claims to customary land and chiefly titles. MNRE Division of Lands is responsible for managing public lands. MNRE Division of Lands and Survey is responsible for mapping and surveying public lands. EPC Office of Corporate Governance develops and manages grievance redress mechanisms. MWCSD Division of Governance is responsible for facilitating contacts, meetings, and coordination between Samoan villages and the various national and external projects and processes that are implemented in Samoan villages. LTA is responsible for public roads.

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376. Non-government stakeholders with an interest in potential project-related land acquisition and resettlement include: (i) affected people and other people who may claim rights over project- related land or non-land assets, (ii) family matai (chiefs) who may represent affected people and other claimants, and (iii) respective village councils of chiefs (fono a matai) that govern village affairs and generally represent village interests in dealing with outsiders. Individuals, their family matai, and their village councils speak for themselves in matters relating to land acquisition and resettlement. Third-party non-government organisations (NGO) do not represent or speak for villagers in such matters. For the purposes of project-related land acquisition and resettlement, non-government stakeholders are located in the village of Magiagi, the sub-village of Alaoa and (in the case of one party with an ancestral connection to the project area) in Moata’a and other urban villages

6.3 Consultations Undertaken

377. EPC, with assistance from the feasibility study team, prepared a Communication and Participation Plan for the project in July of 2018. In January 2019 ADB recruited a national Stakeholder and Community Consultation Specialist to further develop and then facilitate implementation of that plan. By that time, EPC had already carried out several consultations and site visits with a wide range of stakeholders. Documentation of those early meetings was generally good—including photos, identification of participants and/or signed attendance lists, and minutes. The Entura Team Leader attended one meeting at EPC with members of Magiagi village during the project inception mission.

378. EPC held three group consultations during July 2018. The feasibility study team and PMU counterparts first met with representatives of the relevant divisions of MNRE (24 July 2018) to coordinate project activities. The team then met with the CEO of O le Si’osi’omaga Society (a local environmental NGO) on 26 July. Other NGOs were invited but did not attend the meeting. The meeting is relevant here because the CEO of the local NGO questioned whether land in the project area was customary land.

Plate 6.1: Project consultation meeting with MNRE division officers – 24-Jul-18

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379. The feasibility study team and PMU counterparts also met with representatives of Magiagi, Alaoa, and other villages adjacent to and downstream of the project area on 26 July. The ADB Pacific Department social and environment safeguard specialists also attended this meeting.

Plate 6.2: Meeting with representatives of Magiagi, Alaoa, and other villages – 26-Jul-18

380. The 26 July 2018 meeting elicited general support for the project from most who spoke but also concern about dust, noise, and risk from increased traffic on Alaoa Road. One speaker strongly opposed the project over concern the dam might collapse, and a few other speakers mentioned the same concern. Two people from Magiagi and one from Alaoa repeated previous claims that they own lands in the project area as customary land. Each of those claimants said, however, that they would not do anything to disrupt the project.

381. In September and October 2018, one stakeholder, Papalii Malietau Malietoa, made several claims regarding family ownership of and traditional rights in project land as well as claims that the project risked damaging an historic village site called ‘Alaoa’, a prehistoric ‘star mound’, and ancestral family graves. complete report on project stakeholder consultations to date can be found in Volume 2 - Annex H.

382. Due diligence review indicates that: (a) Papalii’s claim to current family ownership of or other rights in the 1921 Ordinance land is not supported by evidence, (b) the ancestral village site of Alaoa lies east of the Vaisigano watershed and thus well outside the current project area, (c) the only known prehistoric star mound lies far outside the project area, (d) and the ancestral family graves also lie well outside the project area. None appear to be at risk from project activities. In short, none of the claims are supported by available evidence. Thus, Papalii is not listed here as an AP. His more general concerns about risks to what ADB calls “physical cultural resources” led, however, to ADB’s decision to fund a LiDAR-assisted surface survey of archaeological features within and adjacent to the footprint of proposed project works. His complaints about the consultation process are dealt with in the Volume 2 – Annex H.

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383. EPC held a public consultation meeting at the Millennia Hotel Fale in Apia (Oct 2018). The minutes include a summary of comments by Papalii Malietau Malietoa. Other stakeholder comments were similar to those received earlier and included several claims for compensation. Substantive claims were investigated in detail during the crop inventory.

Plate 6.3: Public Meeting at Milenia Hotel – 23-Oct-18

384. Public stakeholder comments relevant to this RP include those of a Magiagi man who claimed that his family has cultivated 200 acres at the proposed dam site for several generations and that, as far he is concerned, the land belongs to his family. EPC responded that while the family may have worked the land, the government has owned the land since 1921, but that under ADB guidelines, affected people are entitled to compensation for non-land assets.

385. Another Magiagi stakeholder asked where they would go to plant crops if the land they are using now is flooded by the project. EPC responded that the dam would not affect plantation lands in the upland areas of Magiagi past Fale ole Fee.

386. A third stakeholder from Moata’a/Magiagi claimed that the land belongs to Vaimauga district and that the government had taken the land involuntarily. He requested compensation in the form of other land as exchange. He also requested that Government lease the 1921 Ordinance land from Vaimauga district. EPC did not respond to this claim.

387. A fourth Magiagi/Alaoa stakeholder argued that his family had been cultivating the land for more than 50 years and that the land is the source of their daily living. A fifth Magiagi stakeholder claimed that part of the project land belongs to his family because His Highness Malietoa Tanumafili II gave it to them as a gift. The stakeholder said that his own family had cleared the land and developed an access road (i.e., footpath) to their plantations. He said he does not support the project and threatened to go to battle with government employees if the project continues. EPC did not respond directly to this claim.

388. A subsequent round of five public information and consultation meetings was held in February 2019. One evening meeting was held at a church hall in each of the villages of Magiagi, Vailima/Alaoa, Tanugamanono, Moata’a, and Vaiala. The latter three meetings were for all of communities further downstream of the proposed dam.

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Plate 6.4: EPC project consultation meeting in the village of Magiagi – Feb-19

389. Comments at the five meetings were similar to comments received previously and included both general support for the project and concern that the dam might break. The Magiagi meeting was the only meeting that raised claims for compensation of land or non-land assets (crops only). Substantive claims were investigated in detail during the crop inventory and have been dealt with individually in this RP.

390. At the Vailima/Alaoa consultation meeting, EPC did not make direct reference to potential redevelopment of the Alaoa Road because relevant facts are not yet known. One or more follow- up consultation meeting will be held with Alaoa on that topic once details are known. An inventory of non-land assets will be carried out once plans for Alaoa Road are known in detail.

391. EPC hosted one additional consultation on 10 June 2019 in the large conference hall of the Tanoa Hotel in downtown Apia. No member of the public attended the meeting

6.4 Information disclosure

392. Meetings held to date are presented in the Table 6.1

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Table 6.1: Project consultations and meetings held during EIA due diligence 2018-2019

Source: EIA Volume 2 – Annex H

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6.5 Process for Consultation During Implementation

393. Consultation and information disclosure will continue during subsequent project stages as per the Communication and Participation Plan—that is, during detailed design, again immediately before the start of the civil works, and then during construction. The most significant activities are listed in Table 6.2 in their expected order of occurrence.

Table 6.2: Consultation and information disclosure during implementation

Activity Responsible Parties Participants Notice of intent to resurvey Alaoa Road easement MNRE, LTA, PMU Alaoa/Vailima and explanation of why the easement will be resurveyed. This notice can be made by flyers distributed to relevant households, by public radio, via pulenu’u and local means to logo i le nu’u, and/or by village meeting. Public awareness and consultation meeting(s) to contractor, MNRE, Alaoa/Vailima and lower present and receive comments on draft plans for LTA, PMU Magiagi (Ueligitone) upgrading Alaoa Road and for mitigating noise, dust, traffic congestion, and pedestrian safety risks along Alaoa Road during reconstruction of the road itself and subsequently during construction at the project site. Public awareness and consultation with landowners PMU Landowners and and residents along Alaoa Road whose non-land residents along Alaoa assets may be affected by work to upgrade the road. Road Negotiate arrangements for moving, replacing, or PMU, LTA APs along Alaoa Road compensating for any encroaching non-land assets (fences, hedges, and trees) found to be inside the Alaoa Road easement or otherwise at risk. Disclose RP and Grievance Redress Mechanism PMU APs, Magiagi, (GRM) to and consult with local stakeholders. Alaoa/Vailima The RP will also be posted on the ADB website and distributed to community pulenu’u and sui o le malo (government/community liaison officers). Record and resolve issues raised by APs and other PMU APs, Magiagi, stakeholders and revise RP as necessary. Alaoa/Vailima Pay compensation, if any, for non-land assets to be LTA Relevant APs along affected by construction along Alaoa Road. Payment Alaoa Road must be made before works begin. Pay compensation for non-land assets (crops) in the PMU APs who have claims project area. Payments should be made at a group resulting from project meeting of APs in order to insure transparency. works and from loss of Payment must be made before works begin. land access Public notice to quit project area. Notice by public PMU, contractor General public, Magiagi, radio, print, television, and signs placed at entrance Alaoa/Vailima to Alaoa Road and on Alaoa Road adjacent to water treatment plant. Particular notice to Magiagi and Alaoa/Vailima via pulenu’u.

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6.6 Grievance redress mechanism

6.6.1 Overview

394. Every project should, and is required by the SPS and good practice, to implement, as early as possible, a project-specific grievance redress mechanism (GRM) to receive and facilitate resolution of any concerns or grievances that arise during the course from project initiation through implementation and operation. A single project GRM is used for both social and environmental grievances. Since all the proposed project works would be carried out by or under the guidance and authority of EPC and its PMU, and since project communities and their respective landowners, households, and businesses deal directly with EPC on a regular basis and with the PMU itself on project-related matters, this project will use standard EPC and PMU channels for receiving and dealing with any project-related grievances

395. The scope of the GRM is to address issues related to involuntary resettlement, social and environmental performance, and information disclosure. Under ADB policy any affected person or complainant has the right to file complaints and/or queries on any aspect of the Project, including land acquisition and resettlement, and appeal any decision, practice or activity related to the Project. The PMU are charged with ensuring that grievances and complaints about any aspect of the project are acknowledged and addressed in a timely and effective manner

396. When and where the need arises, this mechanism will be used for addressing any complaints that may arise during the implementation of project. The GRM is scaled to the risks and adverse impacts of the project. It addresses affected people's concerns and complaints promptly, using an understandable and transparent process that is gender responsive, culturally appropriate, and readily accessible to all segments of the affected people at no cost and without retribution. The mechanism does not impede access to the Samoa judicial or administrative remedies. The PMU of EPC will appropriately inform stakeholders about the mechanism before start of commencement of any civil works. The project specific GRM is illustrated as a flow chart in Figure 6.1.

Figure 6.1: Simplified flow chart of the grievance redress mechanism

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397. A process diagram for the GRM is shown in Figure 6.2.

6.6.2 GRM during construction phase

398. During the construction phase affected persons or complainant may have site specific concerns about the construction activities (e.g. levels of construction noise, elevated dust levels, water pollution, speed of construction vehicles on public roads, road safety concerns, etc.) The contractor will be required to set up a site specific GRM so that members of the public have a clear and direct ability to comment on the way the project is impacting upon them.

399. Through the consultation process the contractor will advise members of the community of the GRM process. In addition, the site access and at any point determined by the PMU of EPC, signs will be erected identifying the GRM process is in place for the project and the contact information: physical address, phone contact; and internet access if available.

400. At site level the contractor will identify a community liaison officer (CLO)19 as the formal point of contact. The CLO will be responsible for recording the complaint, assessing the validity of the complaint and identifying actions to address the compliant. This may require escalation of the complaint to more senior members of the contractor organisation (e.g. site project manager20) and, must be formally advised to the construction supervision consultant supporting the PMU.

401. Experience suggests that many issues identified by affected person/complainant can be swiftly and effectively addressed at site level by the CLO, but that the CLO must be clear on the registration of a complaint and how information on that complaint needs to enter the site management procedure. The CLO does not, normally, have delegated powers and therefor any complaint must be immediately referred to the contractor project manager on site in order to determine how the complaint can be addressed. Some cases may be too complex for addressing at site level (e.g. sexual harassment; on and offsite violence, etc.) This may require senior contractor management intervention and the site process is illustrated in the Figure 6.3.

19 An alternative term may be used but shall be identified in the contractor’s CEMP. 20 It is acknowledged and noted that the CLO may not have delegated powers to instruct site staff to initiate actions and therefore the issue will need to be elevated to higher levels in the management chain.

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Figure 6.2: Grievance redress mechanism process

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Figure 6.3: Contractor - construction phase GRM at site level

Construction site incident occurs

Client issues AP lodges Client processing instructions grievance with CONTRACTOR CLO

Contractor CLO Contractor CLO informs senior immediately records Supervision CSC processing CSC informs site complaint (date Consultant (CSC) Client representative name, nature of complaint)

Complaint Initiation: Site refered to rep determines if Conractor complaint can be No Country adressed at site representative level for instruction

Yes Legal / Contractual Instruct CLO. CLO implications gathers supporting information from AP

CLO identifes resolution Approach to plan resolution identified

Contractor CLO informs senior site representative of Resolution Plan

Site Rep agrees No approach with CSC

Yes End Contractor CLO informs AP

AP satisfied No with resolution

Yes

Inititiate Resolution process

AP satisfied No with resolution

Yes

End

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6.7 Outcomes and Conclusions of the Consultations

6.7.1 Benefits

402. During the consultation process the following project benefits were identified:

• Reduce or eliminate flooding of Vaisigano River. • Enhance SWA supply of piped water during dry periods. • Lower turbidity of SWA raw water. • Enhance SWA treatment of piped water during high-rainfall events. • Increase share of renewable energy generation. • Restore Vaisigano minimum “environmental flow” below the Samasoni weir to benefit of bathing, swimming, laundry, and fishing in the river below the Samasoni weir. • Temporary local job opportunities during project construction. • Long-term local job opportunities in project operations after construction. • Local subcontracting opportunities for supply of concrete, equipment, road building, and construction work. • Local small-business opportunities such as catering, cleaning, security work during construction, and use of wood cleared from impoundment area for local building, handicrafts, and firewood. • Gender Action Plan initiatives enhance opportunities for women. • Biomass removal from dam impoundment area may provide a supply of some firewood for local residents subject to EPC contractor plans, costs, and identification of a suitable storage area outside the project site. • Benefits to local residents from upgrade of Alaoa Road and adjacent areas of Cross Island Road.

6.7.2 Costs/adverse impacts

403. The following potential costs/adverse impacts were identified during the consultation process. Note that all identified adverse impacts are to be mitigated by the contractor’s environmental and social management plan and/or by the project’s resettlement plan.

• Short-term increase in traffic noise and dust along Alaoa Road during project works. • Short-term increase in traffic congestion along Alaoa Road and Cross Island Road during project works. • Short-term increase in safety risk for Alaoa residents and school children from increased truck and other vehicle traffic along Alaoa Road during construction. • Short-term increase in risk of social and health problems from any worker camp. • Long-term involuntary restrictions on land use and land access will affect livelihood of several people currently farming illegally on government land in the project area and south of the proposed impoundment area.

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7 Assessment of Impacts

7.1 Overview of Assessment

404. This chapter of the EIA sets out approach to impact assessment and mitigation that can be easily understood by design engineers, construction contractors and implementing agencies. The EIA document is designed to serve the objectives of several stakeholders, including:

• The public – including directly or indirectly affected individuals, individuals and groups with interests for the population and environment (government agencies and NGO); • The authorities in Samoa – to ensure that the project can be designed, constructed and operated to meet all environmental legislation applicable to Samoa; • International financial institutions – in this case the ADB who needs to be assured that the project will be designed, constructed and operated in compliance with the policy requirements in order that funds can be released for the project. • Contractor(s) – a contractor will be engaged through a tendering process by the EPC to construct the project. The EIA document will be used by the contractor to confirm the environmental, social, health and safety factors that they must be incorporated into their working processes. As part of this EIA, an EMP has been prepared and this will be developed further by the contractor, reflecting their approach to the works and timing of activities as identified in their construction program, and incorporated into their own construction EMP (CEMP). The contractor’s CEMP will include all the sub-plans identified in this section of the EIA and site-specific plans as required for specific activities or components of the works. The CEMP will be updated during the construction phase as further details of specific construction techniques become available.

405. The contractor’s CEMP will detail how the contractor will carry out the works in accordance with the EMP. This contractor generated document will be reviewed by EPC, PUMA and ADB, and advice provided to the PMU and the Engineer that it can be approved by the client. The CEMP will become part of the construction contract and environmental performance will be audited against this document.

406. In terms of the assessment the public, government authorities and ADB look to confirm that environmental “aspects” are being addressed i.e. noise and air quality impacts, water quality impacts, ecological and social impacts, etc. Therefore, this impact section of the EIA assesses the project under these topics. The contractor looks at the project in terms of processes i.e. undertaking surveys and investigations, clearing the site, setting up and operating a construction camp, setting up and operating processing facilities (quarries for material, crushing and grading facilities and concrete manufacturing). Therefore, the impact assessment also reports under these process headings which are taken forward into the EMP.

407. The phases of the assessment process are:

• Baseline data collection – site visits, document review, preparation of a rapid environmental assessment, scoping to identify key environmental, social and safety issues and subsequent detailed surveys and studies of key aspects (completed and presented in this EIA);

• Design phase mitigation – environmental, social and safety elements that the designer needs to incorporate into the design. This is either a consultant, or as in this case, a design-build contractor;

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• Construction phase impacts and effects – identification of the environmental, social and safety impacts and effects during the construction phase and the mitigation measures that need to be undertaken by the contractor during the construction phase;

• Operation phase impacts and effects– identification of the environmental, social and safety impacts and effects during the operation of the Alaoa Multi-purpose Dam project operation phase. Including the mitigation needed during the operational phase of the Dam, generally to be actioned by the implementing agency or other government agencies.

7.1.1 A structured approach to critical habitat impact assessment

408. The SPS requires more stringent criteria to be met in order for a project to proceed within an area of critical habitat. In the absence of effective mitigation and management, the clearance of vegetation and loss of habitat will have both direct and indirect effects on the values of the project area which are identified as criteria for critical habitat, and this includes endangered aquatic fauna and avifauna and the wider Apia Catchments KBA. The natural and critical habitat assessment (Volume 2 – Annex K) is based on the guidelines for assessment set out by IFC in Performance Standard 6.

409. To assist in the assessment and integration of the findings of the assessment into the EIA, the Ecological Impact Assessment Guidelines (EIAG)21 of the EIANZ guidelines of the Environment Institute of Australia and New Zealand (EIANZ) have been accessed. The EIAG provides guidance as to the level of adverse effect on target species as a consequence of development. The EIAG has been used to ascertain the following:

• The level of ecological value of the affected ecological values; • The magnitude of ecological effect from the proposed development on the key fauna species and their habitats; • The importance of the ecological effect; and • The overall level of effect to quantify the extent of mitigation and biodiversity offsetting or compensation required.

410. When mitigation is applied, based on the EIANZ guidelines, the overall level of effects of the project on mao and manumea is likely to be ‘Very High’ (‘Very High’ ecological value x ‘High’ magnitude of effects).‘Very high’ represent a high level of effect on ecological or conservation values and warrant avoidance and/or extremely high intensity mitigation and biodiversity offset or compensation remediation actions.

411. In addition, mitigation measures should be designed to achieve at least no net loss of biodiversity. It is recommended that the ‘residual effects’ associated with the loss of habitat for key avifauna and bat species associated with the construction and operation of the dam are addressed using the 10 biodiversity offset principles outlined by the Business and Biodiversity Programme Offsets Programme 2009 (BBOP) as a core objective. Under the principles of the BBOP programme, mitigation for the indigenous vegetation and fauna habitat loss should result in a minimum standard of no net loss of ecological value. Further, any mitigation should preferably result in a net gain for all biodiversity components affected by the Project in terms of potential and actual adverse effects on habitats and threatened species. Accordingly, a comprehensive mitigation and offsetting/compensation package will be needed to compensate for the unavoidable loss of habitat associated with the Dam’s construction and operation.

21https://www.eianz.org/resources/publications/2018---ecological-impact-assessment-guidelines-for-new-zealand- 2nd-edition

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7.1.2 Risk matrix approach for impact assessment

412. The assessment of impact will follow a risk matrix approach where the likelihood of an environmental, safety or social impact occurring is matched with the consequence (severity) of the impact occurring. The matrix ranks potential risks as low, medium, high or extreme, identifying the need for mitigation, and incorporation into the EMP. The assessment of potential severity of the impacts takes into consideration the presence and vulnerability of sensitive receptors and adopts a precautionary approach.

413. All risks classified as medium or higher are considered significant and require detailed assessment (including quantification where appropriate) and mitigation to be identified to reduce impact to an acceptable level. Figure 7.1 sets out the risk matrix derived for this project. This matrix approach can be adopted by the contractor when they are developing their own CEMP.

Figure 7.1: Risk matrix - likelihood and consequence - used for impact assessment

Source: derived for the project

414. The potential adverse environmental and social impacts for each of the pre-construction, construction and operational phase impact areas are described in the following sections.

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7.2 Pre-construction impacts

415. This section assesses impacts and identifies impacts and mitigation that will need to be addressed in the detailed design phase and pre-construction phase of the project.

416. Note that when discussing ecological impacts the majority of information on impact and mitigation is presented in the pre-construction section as the impact and its mitigation must be: (i) included in the contract documents that will be prepared for the project; and/ or (ii) in plans that need to be initiated and implemented separately from the construction contract i.e. outside of contractor control e.g. management functions for EPC, issues relating to ecological restoration and offsets, terrestrial habitat enhancement, education programmes to be implemented by specialists supporting EPC and MNRE. Two plans— biodiversity management and monitoring plan (BMMP) and biodiversity offsetting plan (BOP)—are currently under preparation to ensure the mitigation and offsetting measures required are developed and designed properly, costed, and implementation and monitoring arrangements are identified and agreed with the government. The BMMP and BOP will need to be implemented prior to contract award as some measures will take 3-5 years to function as envisaged in the plans.

7.2.1 Potential impacts on terrestrial critical habitat

417. The Project’s terrestrial AOA represents likely or actual critical habitat for two birds; two lizards; a snail; two palms; and one internationally-recognized area (identified previously in Table 5.13). The magnitude of risks to this Critical Habitat-qualifying biodiversity ranges from Minor-Major, given their rarity, threatened status, conservation importance, and level of public concern about these species and sites (Table 7.1).

418. The overall significance of potential impacts on critical habitat is assessed as low-high (Table 7.1). Approximately 24.4 ha of vegetation clearance will be necessary for dam construction, plus additional clearance for roads and other infrastructure (Stirnemann & Taylor-Smith 2019). Vegetation clearance is considered a major significance impact for all terrestrial priority biodiversity and is certain in terms of likelihood. Vegetation clearance will also result in a level of forest fragmentation and edge effects, which disturb neighbouring habitats through changes in wind, sunlight, temperature and dust (Stirnemann & Taylor-Smith 2019; Wildland 2019). These are significant but relatively small scale and likely to develop in the medium term, so are assessed to be low significance impact. Construction activities may result in (temporary) disturbance (Stirnemann & Taylor-Smith 2019), for example to breeding birds. Impacts of displacement of species owing to this disturbance are therefore assessed to be of low significance.

419. The potential for indirect impacts is also of concern. Without mitigation, there is a risk of hunting of wildlife by construction workers and project roads or vegetation clearance may facilitate increased human access, leading to induced rises in hunting, logging, and forest clearance (Stirnemann & Taylor-Smith 2019). Such impacts can be severe, though will be limited in extent for this Project owing to the limited length of new roads planned. These impacts are considered Low for most biodiversity, but – owing to their greater sensitivity – the potential impact of increased longer-term hunting and forest clearance/degradation owing to induced access, is considered of medium significance for Tooth- billed Pigeon and Mao.

420. Project infrastructure will displace existing agriculture, e.g. in areas mapped as “plantation” by Stirnemann & Taylor-Smith (2019), resulting in another indirect impact. This agriculture is mainly for subsistence, so is likely to move elsewhere, likely nearby – and thus result in more clearance of forest in the Vaisigano catchment. This was quantified by Stirnemann & Taylor-Smith (2019) as 6.6 ha, plus unquantified additional clearance for roads and other infrastructure. These are long-term impacts, so displacement of agriculture is assessed to be a medium significance impact for all terrestrial priority biodiversity.

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421. A potential indirect project impact on critical habitat is the introduction of invasive alien species (IAS). The Global Invasive Species Database (http://www.iucngisd.org/gisd) has records for 78 terrestrial or freshwater IAS in Samoa, of which 46 are plants. IAS can spread rapidly once introduced, significantly modifying habitat for forest-dependent species, and present a very high risk to biodiversity globally. Roads, vegetation clearance, soil disturbance and establishment of non-natural habitats are also likely to encourage invasive alien species to the Project area (Entura 2019a; Stirnemann & Taylor-Smith 2019; Wildland 2019). There is potential for construction machinery, equipment or materials to introduce IAS to forested areas within the Project site, particularly plants – e.g., as seeds within soil on machinery. Invasive alien plants degrade native forest, reducing habitat quality for most native plant and animal species. Invasive alien species can also directly kill native species – e.g., rat and cat predation is a significant threat to both priority bird species identified in the Project area, and species of climbing vine such as fue lautetele (Merremia species) and fue saina (Mikania micrantha) can smother native vegetation (Wildland 2019). On a precautionary basis, the potential impact on terrestrial critical habitat of introduction/spread of invasive alien species is considered of high significance.

7.2.2 Potential impacts on aquatic critical habitat

The Project’s aquatic AOA represents likely or actual critical habitat for four fishes (

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422. Table 5. and Figure 5.28). The magnitude of risks to this critical habitat-qualifying biodiversity ranges from minor-moderate, given their rarity, threatened status, conservation importance, and level of public concern about these species and sites (Table 7.1).

423. Some direct habitat loss will occur, as a result of flooding by the reservoir of c.1.3 km of the middle- east branch of the Vaisigano River (an additional 1 km of the east branch will be flooded but is already Modified Habitat). Direct loss of river habitats is considered a Medium significance impact to Fat- snout Goby, Green Riffle Goby, and Stiphodon hydroreibatus.

424. The dam design will prevent migration of fish and crustaceans, resulting in the loss of these species in the east and middle-east branches of the Vaisigano River (Entura 2019a). These species are a significant component of these river stretches, and their loss would effectively degrade the quality of the remaining aquatic habitat. This impact will affect the unflooded 12.7 km of the east branch and 11.4 km of the middle- east branch, though only 8.2 km of the east branch might currently be considered natural habitat owing to existing offtake for the Fale ole Fee scheme (Entura 2019a). This impact will also necessarily affect a 1.2 km stretch of river directly downstream from the new dam, since migration into this stretch will be discouraged by an in-river structure in order to avoid an ecological sink (Entura 2019 a,b; J. Williams in litt. 2019). Given climbing abilities of the migratory fish in this river, this structure may take the form of a high velocity chute (e.g., Hoover et al. 2003). Prevention of species’ migration upstream of the western branch confluence is considered a high significance impact for Fat-snout Goby, Green Riffle Goby and Stiphodon hydroreibatus, the critical habitat-qualifying species found this far upstream. Although this is a significant impact, it is considered substantially lower than the potential impact of these species migrating upriver of the western branch confluence into an ecological trap at the base of the Project dam.

425. The operation of the dam’s reservoir will regulate flows and may lower water quality downstream, both of which may degrade aquatic environments to a limited degree (Entura 2019a). Given the limited likely degradation from this Project, and existing cumulative downstream impacts, degradation in downstream river habitat quality through flow regulation and reduced water quality is assessed to be of Low significance.

426. As for terrestrial habitats, a potential indirect project impact on aquatic Natural Habitat is the introduction of invasive alien species (IAS). Establishment of non-natural habitats (such as the reservoir) are likely to encourage invasive alien aquatic species to the Project area (Entura 2019a). Of particular concern are Water Hyacinth (Eichhornia crassipes), tilapia (Oreochromis mossambicus) and mosquito fish (Gambusia affinis) (Entura 2019a).

427. There is potential for construction machinery, equipment or materials to introduce Water Hyacinth, and all three species are frequently deliberately introduced by local people. Establishment of Water Hyacinth in a reservoir can degrade downstream rivers, while both tilapia and mosquito fish can outcompete native species and degrade native ecosystems. Considering existing degradation of aquatic habitats, the potential impact of introduction/spread of invasive alien species is considered of medium significance.

7.2.3 Potential impacts on natural habitat

428. All terrestrial Natural Habitat is precautionarily treated as critical habitat, in the absence of detailed information on the distribution of key species. As a result, impacts on terrestrial natural habitat are currently considered to be the same as those on critical habitat.

429. Two areas of non-critical aquatic natural habitat exist in the Vaisigano watershed: the stretch upstream from the middle branch weir, and the east branch stretch upstream of the Fale ole Fee weir. These stretches of river may experience Medium significance impacts from the Project, owing to prevention of aquatic species’ migration upstream and introduction/spread of invasive alien species.

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430. Mitigation and management measures. Table 7.1 summarizes specific mitigation measures relevant to potential Project impacts on critical habitat-qualifying biodiversity. Together, all mitigation measures will be included in the BMMP developed for groups of biodiversity (e.g., terrestrial, aquatic species, birds and bats, etc.).

The specific mitigation measures identified in Table 7.2 are explained in

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Table 7.3, and, on a preliminary basis, are anticipated to result in limited additional financial costs (c. US$10,000 of capital costs,

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431. Table 7.3 will require specialist external support to: (i) implement some of the measures (such as forest restoration), and (ii) provide capacity-building and advisory support to the Project developer and design/construction contractors. Development of the BMMP, currently under preparation, will provide more accuracy for mitigation and monitoring costs and will included a fully-costed time-bound action plan.

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Table 7.1: Impact assessment for critical habitat-qualifying biodiversity in the project area 1

ublic ublic

Environmental Project p Spatial Aspect Impact Magnitude Timeframe Probability

Component Phase scale

oncern

eceptors

receptor

Significance

Sensitivity of of Sensitivity

Consequence

Level of of Level

of change to the to the of change Severity or degree degree or Severity P, C Vegetation clearance. H M M MAJ LT SMALL H DEFINITE H Edge effects and habitat P, C fragmentation resulting from L M L MIN LT SMALL M DEFINITE vegetation clearance. M Apia Catchments Displacement of agriculture, Vegetation Key Biodiversity P, C resulting in vegetation clearance L M L MIN LT SMALL M POSS cover M Area elsewhere. Forest clearance/degradation, O owing to induced access for L M L MIN MT SMALL L POSS people via project roads. L Introduction/spread of invasive P, C L M M MOD LT INTER H POSS alien species. H P, C Vegetation clearance. H H L MOD LT SMALL M DEFINITE M Edge effects and habitat P, C fragmentation resulting from L M L MIN LT SMALL M DEFINITE vegetation clearance. M Displacement of agriculture, Habitat P, C resulting in vegetation clearance L M L MIN LT SMALL M POSS elsewhere. M Forest clearance/degradation, Tooth-billed Pigeon O owing to induced access for L M M MOD LT SMALL M POSSIBLE (Didunculus people via project roads. M strigirostris) and Introduction/spread of invasive Mao (Gymnomyza P, C H H M MAJ LT INTER H POSSIBLE alien species. samoensis) H Displacement of species due to noise, presence of machinery Distribution P, C L M L MIN ST SMALL L POSSIBLE and equipment and presence of L staff. Introduction/spread of invasive P, C, O alien species (causing H H H MAJ LT INTER H POSSIBLE H Mortality predation/smothering). Hunting by construction C H H L MOD ST SMALL L POSSIBLE workers. L

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ublic ublic

Environmental Project p Spatial Aspect Impact Magnitude Timeframe Probability

Component Phase scale

oncern

eceptors

receptor

Significance

Sensitivity of of Sensitivity

Consequence

Level of of Level

of change to the to the of change Severity or degree degree or Severity Induced access for hunters via O H M L MOD MT SMALL M POSSIBLE project roads. M P, C Vegetation clearance. H L L MIN LT SMALL M DEFINITE M Edge effects and habitat Olive Small-scaled P, C fragmentation resulting from L M L MIN LT SMALL M DEFINITE Skink (Emoia vegetation clearance. M lawesi), Samoa Displacement of agriculture, Skink (Emoia Habitat P, C resulting in vegetation clearance L M L MIN LT SMALL M POSS samoensis), elsewhere. M Thaumatodon Forest clearance/degradation, hystricelloides, O owing to induced access for M L L MIN MT SMALL L POSSIBLE Drymophloeus people via project roads. L samoensis and Introduction/spread of invasive Clinostigma P, C H L M MOD LT INTER H POSSIBLE samoense alien species. H Introduction/spread of invasive Mortality P, C, O alien species (causing H L H MOD LT INTER H POSSIBLE predation/smothering). H C, O Loss of habitat in the reservoir. H L L MOD LT SMALL M DEFINITE M Prevention of species' migration Fat-snout Goby upstream of the western branch C, O H L M MOD LT INTER H DEFINITE (Sicyopterus confluence up to dam (site of H pugnans) and Habitat hydropower plant) (habitat loss). Stiphodon Degradation by flow regulation hydroreibatus C, O and reduced downstream water L L L MIN MT SMALL L POSSIBLE quality. L Introduction/spread of invasive P, C M L L MIN LT INTER M POSSIBLE alien species. M Prevention of species' migration C, O upstream of the western branch H L M MOD LT INTER H DEFINITE confluence (habitat loss). H Green Riffle Goby Degradation by flow regulation Habitat (Stiphodon elegans) C, O and reduced downstream water L L L MIN MT SMALL L POSSIBLE quality. L Introduction/spread of invasive P, C M L L MIN LT INTER M POSSIBLE alien species. M

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ublic ublic

Environmental Project p Spatial Aspect Impact Magnitude Timeframe Probability

Component Phase scale

oncern

eceptors

receptor

Significance

Sensitivity of of Sensitivity

Consequence

Level of of Level

of change to the to the of change Severity or degree degree or Severity Degradation by flow regulation Schismatogobius C, O and reduced downstream water L L L MIN MT INTER L POSSIBLE tuimanua and L Habitat quality. Stenogobius Introduction/spread of invasive genivittatus P, C M L L MIN LT INTER M POSSIBLE alien species. M Prevention of species' migration C, O upstream of the western branch L M L MIN LT SMALL M DEFINITE Aquatic Natural M Habitat confluence. Habitat Introduction/spread of invasive P, C L L M MIN LT SMALL M POSSIBLE alien species. M

Note 1: refer to MRDI 2019 for Impact Significance Rating Methodology

Note 2: Project Phase = P-Preparation, C-Construction, WC-Worksheet Closure, O-Operation; Magnitude = MAJ-Major, MOD-Moderate, MIN-Minor; Timeframe = LT-Long-term, MT-Medium-term, ST-Short-term; Spatial Scale = INTER-Intermediate, SMALL-Small; Probability = DEF-Definite, POSS-Possible, UNLIKE-Unlikely

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Table 7.2: Mitigation and management measures for critical habitat-qualifying biodiversity and natural habitat

Responsibility Environmental Project Aspect Impact Mitigation action Development/ Component phase Control implementation CEMP to align with requirements of BMMP and BOP; Contractor to prepare and implement Forest Clearance Plan (FCP) as part of CEMP; PMU, CSC, DB contractor Prior to finalization of project designs and any clearance, SE, ADB identify, clearly mark and map all mature native trees, to facilitate avoidance and minimisation. As FCP minimize clearance of native vegetation at the Project site and around associated roads and other infrastructure; P, C Vegetation clearance. Use already cleared or modified areas for construction PMU, CSC, wherever possible. DB contractor SE, ADB Prioritize avoidance of Ficus and Dysoxylum trees (which may provide seasonal food sources for Tooth-billed Pigeon) and attempt to relocate any of these which cannot be avoided (as per the BMMP).

Replant native vegetation (including Dysoxylum species) in DB contractor, PMU, CSC, Apia Catchments Key Vegetation any temporarily disturbed areas as per the BMMP. MNRE MNRE Biodiversity Area cover Minimize clearance of native vegetation at the Project site Edge effects and habitat and around associated roads and other infrastructure; using PMU, CSC, P, C fragmentation resulting from DB contractor already cleared or modified areas for construction wherever MNRE vegetation clearance. possible. Engage and educate the local community, including Displacement of agriculture, DB contractor, providing incentives to conserve priority biodiversity - such PMU, CSC, P, C resulting in vegetation MNRE, as employment in restoration, invasive species control and MNRE clearance elsewhere. community monitoring - prioritising Project-affected people. Install staffed access control on new roads, allowing access DB contractor, PMU, CSC, to no-one except operational staff, or government officials, MNRE MNRE Forest loss/degradation, and inspecting departing vehicles for poached wildlife. O owing to induced access for Engage and educate the local community, including DB contractor, people via project roads. providing incentives to conserve priority biodiversity - such PMU, CSC, MNRE, as employment in restoration, invasive species control and MNRE community monitoring - prioritising Project-affected people.

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Responsibility Environmental Project Aspect Impact Mitigation action Development/ Component phase Control implementation Develop and implement BMMP and BOP; Take care to avoid introduction of new invasive species to, Recruited and spread of existing invasive species within, the Project specialists, Introduction/spread of area through: PMU, CSC, P, C EPC, MNRE invasive alien species. - washing of vehicles, equipment/materials before entry to MNRE

Project area; DB contractor - monitoring for invasive species; and - control/eradication of invasive species where found. CEMP to align with requirements of BMMP and BOP; Contractor to prepare and implement FCP as part of CEMP; PMU, CSC, Prior to finalization of project designs and any clearance, DB contractor SE, ADB identify, clearly mark and map all mature native trees, to facilitate avoidance and minimisation. Minimize clearance of native vegetation at the Project site and around associated roads and other infrastructure; using already cleared or modified areas for construction wherever PMU, CSC, possible. Prioritize avoidance of Ficus and Dysoxylum trees DB contractor SE, MNRE, P, C Vegetation clearance. (which may provide seasonal food sources for Tooth-billed ADB Pigeon) and attempt to relocate any of these which cannot be avoided. Undertake pre-clearance survey to identify any Mao Avifauna nest/breeding sites (avifauna specialist recruited by CSC); PMU, CSC, specialist, Avoid any vegetation clearance within 150 meters of an SE, ADB DB contractor Tooth-billed Pigeon occupied Tooth-billed Pigeon or Mao nest. Replant native vegetation (including Dysoxylum species) in PMU, CSC, (Didunculus DB contractor strigirostris) and Mao Habitat any temporarily disturbed areas. SE, MNRE (Gymnomyza Minimize clearance of native vegetation at the Project site Edge effects and habitat samoensis) and around associated roads and other infrastructure; using PMU, CSC, P, C fragmentation resulting from DB contractor already cleared or modified areas for construction wherever MNRE vegetation clearance. possible. Engage and educate the local community, including Displacement of agriculture, DB contractor, providing incentives to conserve priority biodiversity - such PMU, CSC, P, C resulting in vegetation MNRE, as employment in restoration, invasive species control and MNRE clearance elsewhere. community monitoring - prioritising Project-affected people. Install staffed access control on new roads, allowing access DB contractor, PMU, CSC, to no-one except operational staff, or government officials, MNRE MNRE and inspecting departing vehicles for poached wildlife. Forest loss/degradation, O owing to induced access for Engage and educate the local community, including DB contractor, people via project roads. providing incentives to conserve priority biodiversity - such PMU, CSC, MNRE, as employment in restoration, invasive species control and MNRE community monitoring - prioritising Project-affected people.

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Responsibility Environmental Project Aspect Impact Mitigation action Development/ Component phase Control implementation Take care to avoid introduction of new invasive species to, and spread of existing invasive species within, the Project Recruited area through: specialists, Introduction/spread of PMU, CSC, P, C - washing of vehicles, equipment and supplies before entry EPC, MNRE invasive alien species. MNRE to the Project area; - monitoring for invasive species; and DB contractor - control/eradication of invasive species where found. CEMP to align with requirements of BMMP and BOP; Regularly maintain and inspect/certificate all vehicles, PMU, CSC, Distribution DB contractor equipment and machinery to ensure that noise levels SE, ADB conform to national standards. Displacement of species Undertake pre-clearance survey to identify any Mao Avifauna due to noise, presence of nest/breeding sites (avifauna specialist recruited by CSC); PMU, CSC, P, C specialist, machinery and equipment Avoid any construction activity during the most sensitive SE, ADB DB contractor and presence of staff. Mao breeding period (June-August inclusive). Undertake pre-clearance survey to identify any Mao Avifauna nest/breeding sites (avifauna specialist recruited by CSC); PMU, CSC, specialist, Avoid any construction activity within 150 meters of an SE, ADB DB contractor occupied Tooth-billed Pigeon or Mao nest. Take care to avoid introduction of new invasive species to, Tooth-billed Pigeon and spread of existing invasive species within, the Project Recruited Introduction/spread of (Didunculus area through: specialists, invasive alien species PMU, CSC, strigirostris) and Mao P, C, O - washing of vehicles, equipment and supplies before entry EPC, MNRE (causing MNRE (Gymnomyza to the Project area; predation/smothering). samoensis) - monitoring for invasive species; and DB contractor - control/eradication of invasive species where found. Implement a strict code of conduct forbidding Mortality of individuals, from PMU, CSC, hunting/trapping, and purchase of wildlife, with heavy C poaching by construction DB contractor SE, MNRE, Mortality penalties. Train all personnel on this code of conduct, and workers. community its justification. Install staffed access control on new roads, allowing access DB contractor, PMU, CSC, to no-one except operational staff, or government officials, MNRE, MNRE Mortality of individuals, and inspecting departing vehicles for poached wildlife. community O owing to induced access for Engage and educate the local community, including DB contractor, hunters via project roads. providing incentives to conserve priority biodiversity - such PMU, CSC, MNRE, as employment in restoration, invasive species control and MNRE community monitoring - prioritising Project-affected people. Olive Small-scaled CEMP to align with requirements of BMMP and BOP; Skink (Emoia lawesi), Contractor to prepare and implement FCP as part of CEMP; PMU, CSC, Samoa Skink (Emoia Habitat P, C Vegetation clearance. Prior to finalization of project designs and any clearance, DB contractor, MNRE, ADB samoensis), identify, clearly mark and map all mature native trees, to Thaumatodon facilitate avoidance and minimisation.

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Responsibility Environmental Project Aspect Impact Mitigation action Development/ Component phase Control implementation hystricelloides, Minimize clearance of native vegetation at the Project site Drymophloeus and around associated roads and other infrastructure; using DB contractor, PMU, CSC, samoensis and already cleared or modified areas for construction wherever MNRE MNRE Clinostigma possible. samoense Replant native vegetation (including Dysoxylum species) in any temporarily disturbed areas. Minimize clearance of native vegetation at the Project site DB contractor, PMU, CSC, and around associated roads and other infrastructure; using MNRE MNRE already cleared or modified areas for construction wherever possible Engage and educate the local community, including Edge effects and habitat DB contractor, providing incentives to conserve priority biodiversity - such PMU, CSC, P, C fragmentation resulting from MNRE, as employment in restoration, invasive species control and MNRE vegetation clearance. community monitoring - prioritising Project-affected people. Displacement of agriculture, Install staffed access control on new roads, allowing access DB contractor, PMU, CSC, P, C resulting in vegetation to no-one except operational staff, or government officials. MNRE MNRE clearance elsewhere. Engage and educate the local community, including Olive Small-scaled DB contractor, providing incentives to conserve priority biodiversity - such PMU, CSC, Skink (Emoia lawesi), Habitat MNRE, as employment in restoration, invasive species control and MNRE Samoa Skink (Emoia community monitoring - prioritising Project-affected people. samoensis), Forest loss/degradation, Take care to avoid introduction of new invasive species to, Thaumatodon O owing to induced access for and spread of existing invasive species within, the Project hystricelloides, people via project roads. area through: Drymophloeus DB contractor, PMU, CSC, - washing of vehicles, equipment and supplies before entry samoensis and MNRE MNRE to the Project area; Clinostigma - monitoring for invasive species; and samoense - control/eradication of invasive species where found. Take care to avoid introduction of new invasive species to, and spread of existing invasive species within, the Project Introduction/spread of area through: invasive alien species DB contractor, PMU, CSC, Mortality P, C, O - washing of vehicles, equipment and supplies before entry (causing MNRE MNRE to the Project area; predation/smothering). - monitoring for invasive species; and - control/eradication of invasive species where found. Recruited Loss of habitat in the None feasible; specialists, PMU, CSC, C, O Fat-snout Goby reservoir. Preparation and implementation of BOP EPC, MNRE MNRE, ADB (Sicyopterus pugnans) Habitat and Stiphodon Prevention of species' BMMP, BOP Structure installed upstream of Samasoni weir and hydroreibatus migration upstream of the specialists and EPC, MNRE, C, O downstream of the confluence of the western branch, to western branch confluence incorporated into contractor encourage fishes up the western (and to be restored branch (habitat loss). detailed design

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Responsibility Environmental Project Aspect Impact Mitigation action Development/ Component phase Control implementation – which will be better quality habitat and the fish can go farther upstream) rather than up the middle branch

C, O Degradation by flow None feasible; Recruited regulation and reduced Preparation and implementation of BOP specialists, PMU, CSC, downstream water quality. EPC, MNRE MNRE, ADB

Issue to be addressed and managed through BMMP and BOP; Take care to avoid introduction of new invasive species to, BMMP, BOP Introduction/spread of and spread of existing invasive species within, the Project specialists PMU, CSC, P, C invasive alien species and area through: MNRE, ADB pests. - washing of vehicles, equipment and supplies before entry DB contractor to the Project area; - monitoring for invasive species; and - control/eradication of invasive species where found. Prevention of species' None feasible; Recruited migration upstream of the Preparation and implementation of BOP specialists, PMU, CSC, C, O western branch confluence EPC, MNRE MNRE, ADB (habitat loss). C, O Degradation by flow Implementation of environmental flows as per EIA and regulation and reduced Volume 2 – Annex D Environmental Flow Assessment; EPC, recruited downstream water quality Preparation and implementation of BOP specialists, PMU, CSC, MNRE MNRE, ADB

Green Riffle Goby Habitat (Stiphodon elegans) Issue to be addressed and managed through BMMP and BOP; CEMP aligned with BMMP and BOP as required; Take care to avoid introduction of new invasive species to, BMMP, BOP Introduction/spread of and spread of existing invasive species within, the Project specialists PMU, CSC, P, C invasive alien species. area through: MNRE, ADB - washing of vehicles, equipment and supplies before entry DB contractor to the Project area; - monitoring for invasive species; and - control/eradication of invasive species where found. C, O Degradation by flow Implementation of environmental flows as per EIA and EPC, recruited Schismatogobius regulation and reduced Volume 2 – Annex D Environmental Flow Assessment; PMU, CSC, Habitat specialists, tuimanua and downstream water quality. Preparation and implementation of BOP MNRE, ADB MNRE

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Responsibility Environmental Project Aspect Impact Mitigation action Development/ Component phase Control implementation Stenogobius Issue to be addressed and managed through BMMP and genivittatus BOP; CEMP aligned with BMMP and BOP as required; Take care to avoid introduction of new invasive species to, BMMP, BOP Introduction/spread of and spread of existing invasive species within, the Project specialists PMU, CSC, P, C invasive alien species. area through: MNRE, ADB - washing of vehicles, equipment and supplies before entry DB contractor to the Project area; - monitoring for invasive species; and - control/eradication of invasive species where found. Design of fish ladder and structure upstream of the Prevention of species' Samasoni weir and downstream of the confluence of the PMU, CSC, C, O migration upstream of the DB contractor western branch, to encourage fishes up the western (and to MNRE, ADB western branch confluence. be restored branch) rather than up the middle branch Take care to avoid introduction of new invasive species to, and spread of existing invasive species within, the Project BMMP, BOP Aquatic Natural area through: Habitat specialists PMU, CSC, Habitat - washing of vehicles, equipment and supplies before entry MNRE, ADB Introduction/spread of to the Project area; P, C DB contractor invasive alien species. - monitoring for invasive species; and - control/eradication of invasive species where found. DB contractor, Educate local people on the dangers of deliberate PMU, CSC, MNRE, introductions of invasive species. MNRE community

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Table 7.3: Summary of specific measures to protect critical habitat (with preliminary costs)

Short Form Long Form Rationale Process and Outcome Cost and Responsibility 1 No hunting Implement a strict code Project construction and operation staff and contractors The Project will thus develop a strict No significant cost to of conduct forbidding are a potential risk to priority fauna, particularly birds. code of conduct forbidding any hunting, project hunting/trapping, and Tooth-billed Pigeon has traditionally been a target for trapping, purchase or possession of [Construction] and purchase of wildlife, with hunters (Stirnemann & Taylor-Smith 2019), and any wildlife, enforced with heavy penalties [Operation] heavy penalties. Train all mortality of this species would have severe impacts given for individuals and any companies that personnel on this code its much depleted populations. Other species are also, employ them, and supported by a of conduct, and its however, potentially susceptible to harvest in future (e.g., training program that explains these justification for the reptile trade; Auliya et al. 2016). rules and their justification. This mitigation measure has no significant financial or time cost to operating a good-practice Project. 2 Limit Access Install staffed access The Project will establish almost 3 km of new access Enforcement will consist of physical, small capital costs control on new roads, roads. Without any restrictions, these are likely to staffed barriers to access on any new for establishment of allowing access to no- stimulate increased access by local people, which may Project roads, allowing access to no- barriers and staff hut one except operational lead to increased levels of forest loss, degradation and one except Project staff, contractors, or (

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Short Form Long Form Rationale Process and Outcome Cost and Responsibility lost land. Without such commitment, the Project will be inducing displacement of agriculture, and incur the need for more costly compensation for impacts. 4 Introducing Take care to avoid Invasive species are one of the most significant global In order to manage the risk of Costs of a wash new invasive introduction of new threats to biodiversity, and their management is thus a key introducing or spreading invasive station unlikely to species invasive species to, and consideration for Projects under ADB safeguards (ADB species into the forested area within exceed US$5,000. spread of existing 2009). Invasive species may be spread in many ways, in which this Project is proposed, an Staffing costs can be invasive species within, particular through transport into a project area of materials Invasive Species Management Plan will cost-effectively the Project area or equipment from outside that area be developed. This will include at combined with those minimum: pressure washing of for Project area vehicles, equipment and supplies access barriers before entry to Project roads (ideally at [Construction] one access point before the Project); monitoring for invasive species across the Project area; and control/eradication of invasive species where found in the Project area. Washing need not use substantial amounts of water, and can be replaced by brushing during any periods of low water supply. Such preventative measures are generally considerably less costly than measures to control or eradicate invasive species 5 Map all Prior to finalization of Understanding of the distribution of native vegetation in It is important for a botanist to conduct Costs of such mature trees project designs and any the Project area is currently limited. Further, native trees detailed ground surveys prior to botanical surveys are before work clearance, identify, (particularly fruiting trees such as Ficus and Dysoxylum finalization of Project designs in order likely to be limited commences clearly mark and map all species) in otherwise cleared “plantation” areas are of to map native vegetation – particularly (

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Short Form Long Form Rationale Process and Outcome Cost and Responsibility avoidance of Ficus and Project roads after construction has finished. Minimization Dysoxylum trees (which of forest clearance is not anticipated to cause any may provide seasonal significant time delay for the Project and will actually save food sources for Tooth- the Project money as it will reduce the cost of billed Pigeon), and compensation required for impacts on forest. attempt to relocate any of these which cannot be avoided 7 Replanting of Replant native Some vegetation clearance may be necessary for Project Restoration of native species will Bonin (2008) native vegetation (including construction, notably an aggregate crushing plant, particularly focus on those of value to estimated restoration vegetation Dysoxylum species) in batching plant, site office, and stock-piles (including for priority biodiversity, such as Dysoxylum and invasive plant any temporarily aggregate and steel pipe). Where possible, these will be species that provide fruit for Tooth- control cost at site in disturbed areas established in existing open, modified areas (Stirnemann billed Pigeon. Stirnemann & Taylor- the Vaisigano & Taylor-Smith 2019). Where such avoidance is not Smith (2019) provide detailed watershed to be possible, these areas will be restored to native vegetation recommendations (in Annex J - Section c.US$700 / year. as soon as they are no longer needed. It is estimated that 6.2) for replanting, which will be With economies of there may be a total of 1.06 ha of such temporary incorporated into a Project Restoration scale, cost of disturbance and restoration. Where it is not possible to Plan. restoring 1.06 ha avoid native trees, the Project will determine whether over 30 years these can be replanted in temporarily disturbed areas or Development and implementation of estimated at areas near the Project BMMP and BOP ~US$30,000

BMMP/BOP sperate financing [Design] & [Operation] 8 Maintain Regularly maintain and Apart from hunting and vegetation clearance, native fauna To minimize such disturbance, the No significant cost to vehicles inspect/certify all most likely to be disturbed by Project noise. Project will adopt an international project accessing the vehicles, equipment and standard to follow (such as IFC 2007), [Construction] site machinery to ensure and regularly inspect and approve all noise levels conform to vehicles, equipment and machinery to international standards ensure conformance with this standard. 9 Avoid Avoid any construction Of the priority species, disturbance is likely to have the Construction activity, including No direct financial construction activity during the most most severe impacts on birds, given their ability to move vegetation clearance, will thus be cost but potential in Mao sensitive Mao breeding away from disturbance. This may not be a major impact at conducted outside of the most sensitive costs due to delays breeding period (June-August some times of the year, but can be significant during the nesting period for Mao, i.e. June to [Construction] season inclusive) breeding season as it can cause birds to abandon nests August (R. Stirnemann in litt. 2019) – and produce no young that year. This is of most ideally avoiding construction activity significance for Mao, which are known to breed in the throughout the breeding season (June Project area (Stirnemann & Taylor-Smith 2019). to October) where possible (Stirnemann & Taylor-Smith 2019).

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Short Form Long Form Rationale Process and Outcome Cost and Responsibility 10 Avoid work Avoid any construction The most sensitive areas for disturbance of birds during This mitigation measure has limited limited financial costs close to Mao activity within 150 the breeding season (Section 5.1.9) are active nests. financial cost, but other financial or time for surveys nests meters of an occupied Immediately prior to any vegetation clearance, an costs may be incurred if priority (

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Following the impact assessment methodology used in MRDI (2019), residual impacts for Critical Habitat-qualifying (“priority”) biodiversity and Natural Habitat (Table 5.13), after the application of Project mitigation are assessed in

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432. Table 7.3 and Table 7.4. The ADB SPS requires equivalence in biodiversity compensation. Among other things, this means that the combination of area and quality (“extent × condition”) of each habitat delivered by compensation is equivalent to the combined area and quality of the impacted habitat. The implications of this are explored below for Critical Habitat and Natural Habitat impacts.

7.2.4 Residual impacts on terrestrial critical habitat

433. Stirnemann & Taylor-Smith (2019) estimated a residual loss of 24.4 ha of terrestrial Critical Habitat, under the footprint of the Project’s dam wall and reservoir. Additional long-term residual losses are predicted from vegetation clearance for the penstock pipe, small power station and associated roads, plus edge effects related to Project infrastructure. Temporary residual losses are predicted from quarries, an aggregate crushing plant, a batching plant, project site office and stockpiles. The residual impacts of loss of terrestrial vegetation are assessed to be of Medium significance. There is also anticipated to be a Low significance residual fragmentation impact for terrestrial species, owing to the Project reservoir and roads.

434. It is challenging to assess habitat quality for Tooth-billed Pigeon (R. Stirnemann pers. comm. 2019) given extremely limited information about its ecology (and thus, for example, what habitat factors determine breeding success), its movements in relation to varying seasonal fruiting of patches of trees of the same species (thus, for example, patches of trees that fruit in June may be of no value if fruit availability in January is limiting), and the varying resilience of different areas to cyclone damage (valleys being much more important refugia in such circumstances). The species appears more tied to fruit availability than overall forest quality; readily visiting isolated fruit trees in otherwise cleared areas.

435. It is likely that invasive alien animals (notably rats and cats) currently play the largest role in limiting populations of Mao, and possibly also Tooth-billed Pigeon, and their density is thus the largest current determinant of habitat quality (R. Stirnemann pers. comm. 2019).

436. Project cleared vegetation for the Project dam and reservoir is estimated to comprise 17.8 ha of secondary forest and 6.6 ha of mixed “plantation” (subsistence home garden) (Stirnemann & Taylor-Smith 2019). The secondary forest is of variable quality, with a mix of native and non-native plant species. Given available data and recognizing the challenges explained above, for the purposes of this assessment secondary forest in the Project vicinity is considered overall approximately 75% of natural quality and “plantation” 60% of natural quality. These quality estimates are preliminary and need further consideration and refinement. These impacts from the Project footprint can thus be considered as (17.8 × 0.75) + (6.6×0.6) = 17.31 Quality Hectares of forest.

437. Based on current Project designs, similar quantitative estimates can be made for all Project infrastructure (Table 7.4). Most estimates are less precise than those for the Project dam and reservoir, and do not benefit from forest cover maps. At present, other infrastructure is thus precautionarily considered to fall on secondary forest (75% quality) rather than plantation. Several other assumptions are made: (i) access roads will total 2.96 km (including 990 m of temporary roads for construction, which will be inundated by the reservoir) and involve clearance of a c.10 m-wide corridor (Andrew Taylor in litt. 2019); (ii) the penstock pipeline will be c.400 m long (Richard Herweynen in litt. 2019) and involve clearance of a c.5 m- wide corridor; (iii) agriculture in other areas occurs at similar density to that within the dam and reservoir (c.30% of land cover); (iv) edge effects will equate to 50% loss of current forest quality within 10 m of all infrastructure (a precautionary simplification of real effects; Stirnemann & Taylor-Smith 2019); (v) quarry sites and construction access roads fall entirely within the reservoir footprint; (vi) mitigation can largely/entirely remove the risk of agriculture being displaced to new locations, with resulting forest clearance impacts; and (vii) restoration will proceed sufficiently fast that edge effects from temporary construction infrastructure will be negligible.

Table 7.4: Quantification of Project impacts on terrestrial vegetation

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Estimated Estimated area Estimated Impact Impact (Quality Duration (hectares) forest quality Hectares) Dam and reservoir 17.8 75% 13.35 Long-term 6.6 60% 3.96 Long-term Penstock pipe 0.2 75% 0.15 Long-term Power station 0.04 75% 0.03 Long-term Access roads 1.97 75% 1.4775 Long-term Edge effects 107.2 75% 40.2 Long-term Construction access roads 0.99 75% 0 Short-term Quarries 0 75% 0 Short-term Aggregate crushing plant 0.2 75% 0.15 Short-term Batching plant 0.06 75% 0.045 Short-term Project site office 0.1 75% 0.075 Short-term Stockpiles (aggregate & steel pipe) 0.7 75% 0.525 Short-term Totals 134.8 59.91 Long-term 1.06 0.795 Short-term

Source: Volume 2 – Annex K Natural and Critical Habitat Assessment (2019)

438. The assessment also assumes that all temporary/short-term impacts will be restored and can reach 25% quality in a reasonable offset timeframe (20-30 years). On the basis of these assumptions, and the figures in Table 7.4, the Project can be considered to have long-term terrestrial residual impacts of 59.1675 + (0.795 - (1.06*0.25)) = c.59.7 Quality Hectares. Further elaboration of the Project design, refinement of assumptions, and/or habitat mapping across the Project area will be used to refine this preliminary estimate.

439. Residual impacts on terrestrial natural habitat are currently considered to be the same as for critical habitat, since the information does not currently exist to distinguish these habitat classes on land.

7.2.5 Residual impacts on aquatic critical habitat

440. For aquatic critical habitat, there are predicted to be three low-high significance residual impacts. Habitat quality impacts have been quantified, in consultation with the feasibility study’s aquatic ecologist William Elvey (in litt. 2019). Although habitat quality impacts are based on expert opinion at present, they provide a useful basis for comparison with potential gains.

441. A high significance residual impact is the indirect loss of c.11.4km of aquatic critical habitat in the middle-east branch upstream of the Project reservoir, and c.1.2 km immediately downstream of the Project dam, through prevention/discouragement of fish migration upstream of the western branch confluence. The species that qualify these stretches of river as critical habitat require migratory connectivity, and so will be eliminated by the Project. In the middle-east branch, c.9.7km is in a natural condition (perhaps 75% quality for the purposes of this assessment). Another 3 km is degraded by abstraction for the existing Alaoa headpond and other downstream flow regulation (so might be considered c.60% quality), of which 1.3 km will be wholly flooded (as discussed above).

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442. The 1.2km immediately downstream of the Project dam is currently c.65% quality at present. Overall, this impact can thus be considered as (9.7 × 0.75) + ((3-1.3) × 0.6) + (1.2×0.65) = 9.075 Quality Kilometres of river critical habitat.

443. Another medium significance residual impact is the direct loss of c.1.3km of river habitat owing to flooding under the Project reservoir. This is considered broadly natural condition, but impacted by downstream flow regulation (so, for the purposes of this assessment, perhaps 65% quality), and so these impacts can be considered as 1.3×0.65 = 0.845 Quality Kilometres of river critical habitat.

444. There is also predicted to be a Low significance residual impact to aquatic critical habitat through modification of flows, and potentially reduced water quality, downstream of the Project dam. This impact will affect c.1km of broadly natural habitat (~65% quality) from the Project power station to the Samasoni weir, c.4.2 km of heavily Modified Habitat (considered only 10% quality for the purposes of this assessment) from Samasoni weir to Samasoni power station, and c.1km of modified habitat (~50% quality) from the power station to Apia Bay. Further modification of already highly altered flows is not likely to substantially increase cumulative impacts; speculatively by 10%. This degradation impact may thus be considered to be: (1×0.1) + (4.2×0.1) + (1×0.1) = 0.62 Quality Kilometres of river critical habitat.

445. Considering all three impacts discussed above, total Project residual impacts on aquatic critical habitat can be considered to be 10.54 Quality Kilometres of river critical habitat.

446. Residual impacts on aquatic natural habitat. Two areas of non-Critical aquatic Natural Habitat exist in the Vaisigano watershed: the stretch upstream from the middle branch weir, and the east branch stretch upstream of the Fale ole Fee weir (Figure 5.29Error! Reference source not found.). The latter is expected to experience residual Project impacts through elimination of migratory species upstream of the dam barrier. This will degrade c.8.2km of natural habitat in the east branch. This is currently in a degraded condition (~50% quality) and – for the purposes of this assessment – could be considered to be degraded to c.40% quality modified habitat. Overall, this degradation impact may be considered to be: (8.2 × (0.5- 0.4)) = 0.82 Quality Kilometres of river natural habitat. While this estimate is imprecise and subjective, it would be challenging to improve it significantly without objective monitoring of quality metrics across the Vaisigano watershed.

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Table 7.5: Residual impacts after mitigation for critical habitat-qualifying biodiversity Residual impact after implementation of Significance mitigation measures Environmental Project of impact Preparation, Aspect Impact Operation Phase Key residual impacts component phase without construction, mitigation and worksite Day 1 Year 10 closure phases Long-term loss of c.27 ha of vegetation; P, C Vegetation clearance. M Medium Medium Medium fragmentation by roads and reservoir. Long-term loss of c. Edge effects and habitat fragmentation 107 ha of vegetation; P, C M Medium Medium Medium resulting from vegetation clearance. fragmentation by Apia Catchments Key Vegetation roads and reservoir. Biodiversity Area cover Displacement of agriculture, resulting in P, C L Negligible Negligible Negligible n/a vegetation clearance elsewhere. Forest loss/degradation, owing to O induced access for people via project L Negligible Negligible Negligible n/a roads. Introduction/spread of invasive alien P, C H Negligible Negligible Negligible n/a species. Long-term loss of c.27 P, C Vegetation clearance. M Medium Medium Medium ha of vegetation. Long-term loss of c. Edge effects and habitat fragmentation 107 ha of vegetation; P, C M Medium Medium Medium resulting from vegetation clearance. fragmentation by roads and reservoir. Habitat Displacement of agriculture, resulting in P, C L Negligible Negligible Negligible n/a vegetation clearance elsewhere. Forest loss/degradation, owing to Tooth-billed Pigeon O induced access for people via project M Negligible Negligible Negligible n/a (Didunculus strigirostris) roads. Introduction/spread of invasive alien and Mao (Gymnomyza P, C H Negligible Negligible Negligible n/a samoensis) species. Displacement of species due to noise, Distribution P, C presence of machinery and equipment L Low Negligible Negligible n/a and presence of staff. Introduction/spread of invasive alien P, C, O H Negligible Negligible Negligible n/a species (causing predation/smothering). Mortality of individuals, from poaching by Mortality C L Negligible Negligible Negligible n/a construction workers. Mortality of individuals, owing to induced O M Negligible Negligible Negligible n/a access for hunters via project roads.

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Residual impact after implementation of Significance mitigation measures Environmental Project of impact Preparation, Aspect Impact Operation Phase Key residual impacts component phase without construction, mitigation and worksite Day 1 Year 10 closure phases Long-term loss of c.27 P, C Vegetation clearance. H Medium Medium Medium ha of vegetation; fragmentation Long-term loss of c. Olive Small-scaled Skink Edge effects and habitat fragmentation 107 ha of vegetation; P, C M Medium Medium Medium (Emoia lawesi), Samoa resulting from vegetation clearance. fragmentation by Skink (Emoia roads and reservoir. Habitat samoensis), Displacement of agriculture, resulting in P, C L Negligible Negligible Negligible n/a Thaumatodon vegetation clearance elsewhere. hystricelloides, Forest loss/degradation, owing to Drymophloeus O induced access for people via project L Negligible Negligible Negligible n/a samoensis and roads. Clinostigma samoense Introduction/spread of invasive alien P, C H Negligible Negligible Negligible n/a species. Introduction/spread of invasive alien Mortality P, C, O H Negligible Negligible Negligible n/a species (causing predation/smothering). Long-term loss of c.1.3 C, O Loss of habitat in the reservoir. M Medium Medium Medium km of aquatic habitat. Prevention of species' migration Long-term loss of C, O upstream of the western branch H High High High c.12.6 km of habitat Fat-snout Goby confluence (habitat loss). upstream. (Sicyopterus pugnans) Degradation of c.6.5 Habitat and Stiphodon km of habitat Degradation by flow regulation and downstream by hydroreibatus C, O L L L L reduced downstream water quality. modified flows, and potentially reduced water quality. Introduction/spread of invasive alien P, C M Negligible Negligible Negligible n/a species. Prevention of species' migration Long-term loss of c.1.2 C, O upstream of the western branch H High High High km of aquatic habitat. confluence (habitat loss). Degradation of c.6.5 km of habitat Green Riffle Goby Habitat Degradation by flow regulation and downstream by (Stiphodon elegans) C, O L L L L reduced downstream water quality. modified flows, and potentially reduced water quality. Introduction/spread of invasive alien P, C M Negligible Negligible Negligible n/a species.

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Table 7.6: Summary of approach to residual impacts (including costs)

Habitat Type Features Description Quantification Equivalent loss residual loss of 24.4 ha of secondary forest in the Project vicinity is terrestrial Critical Habitat, comprise 17.8 ha of considered overall approximately 75% of natural 17.31 Quality Hectares of Terrestrial critical habitat under the footprint of the secondary forest and 6.6 quality and “plantation” 60% of natural quality. forest Project’s dam wall and ha of mixed “plantation” (17.8×0.75) + (6.6×0.6) = 17.31 Quality Hectares

reservoir of forest Long term project infrastructure: 2.96Km access roads 41.88 Quality Hectares of See Table 7.4 (1.97Ha); Power stn footprint (0.04Ha); 400m penstock 1.4775+0.03+0.15+40.2 forest pipeline (0.2Ha); edge effects (107.2Ha) Short term impacts will be restored and can reach Forest Habitat Forest Short term project infrastructure: crushing plant and 0.53Quality Hectares of See Table 7.4 25% quality in 20/30 years. batching plant site office stock-piles 1.06Ha forest 0.795 - (1.06 x 0.25) 59.72 Quality Hectares of TOTAL forest 11.4Km of middle east 9.7Km in natural condition Aquatic Critical (high branch (75% quality) and 3Km 9.075 Quality Km of river (9.7×0.75) + ((3-1.3) × 0.6) + (1.2×0.65) significance) 1.2km immediately d/s of degraded by abstraction Critical Habitat

dam 60% quality

Direct loss of 1.3Km of impacted by downstream Aquatic Critical (medium 0.845 quality Km of river river habitat due to flow regulation (65% 1.3 x 0.65 significance) Critical habitat inundation by dam quality) 1Km natural habitat (65% quality) power st’n to

Samasoni weir. Aquatic Habitat Aquatic Aquatic Critical (low 4.2Km heavily modified habitat (10% quality) Samasoni 0.62 quality Km of river (1×0.1) + (4.2×0.1) + (1×0.1) = significance) Weir to Samasoni power st’n. Critical habitat 1Km Modified habitat (50% quality) Samasoni power st’n to Apia bay 10.54 quality Km of river TOTAL Critical habitat 8.2Km Natural habitat in Aquatic Natural (non- East Branch (50% quality), 0.82 quality Km of river 8.2 X (0.5-0.4) critical) 40% quality modified Critical habitat habitat.

Source: Volume 2 – Annex K Natural and Critical Habitat Assessment (2019)

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7.2.6 No net loss/net gain approach

447. The SPS requires ‘measures to avoid, minimize, or mitigate potentially adverse impacts and risks’. Nonetheless, some residual impacts cannot be fully mitigated, and–on a preliminary basis–it is recognized that this Project is likely to have significant, though small, residual impacts of forest loss and fragmentation. In such cases, the SPS requires ‘compensatory measures, such as biodiversity offsets, to achieve no net loss or a net gain of the affected biodiversity’. These compensatory measures should ensure that, overall, the high biodiversity value of the areas of natural and critical habitat is maintained, along with populations of endangered and critically endangered species.

448. Drawing on international good practice, the choice of an appropriate compensation measure to reach no net loss or net gain should – in particular – be comparable, additional and lasting (e.g., Gardner et al. 2013). “Comparable” means that the compensation measure should produce similar biodiversity gains to residual impacts (in scale, type of biodiversity, etc.), equating – for this Project – to gains in habitat for six terrestrial and five fish species, ideally in or near the Apia Catchments Key Biodiversity Area. “Additional” means that gains produced by the compensation measure would not have happened anyway, in the absence of the Project. “Lasting” means that gains should last as long as residual impacts, in the case of this Project into the long-term. The compensation measure should ideally also be practical, i.e. cost- effective and relatively easy to implement – such as through a contract to one entity, rather than through complex multi-institutional partnerships.

449. This Project’s predicted residual impacts are: direct loss, and fragmentation, of terrestrial critical habitat; direct and indirect loss and degradation of aquatic critical habitat; and degradation of aquatic Natural Habitat. The SPS requires compensation/offset measures to address these residual impacts. Such offsetting and/or compensation for ADB-financed projects is required to focus on similar biodiversity. As such, this Project will need to improve the status of the impacted forest type and the priority species it holds and improve the status of similar river habitats in the catchment. Approaches will be detailed further in the BOP (covering terrestrial, aquatic, policy and institutional support).

450. The total cost of the approaches is initially estimated at US$155,000-320,000/year for forest restoration and invasive species control, plus US$250,000 for translocation of Mao, pending more detailed planning and budgeting. Abundant experience elsewhere demonstrates that is not appropriate to budget for such costs on an annual basis (e.g., from annual Project revenues). As such, the optimal approach is an up-front trust fund-type mechanism, which can generate annual requirements. On a preliminary basis, this endowment would need to be c.US$4.2-8.3 million. The costs will be further developed to be more accurate in the design and development of the BOP.

451. Overall, the Project can demonstrate that it can meet SPS requirements for projects in areas of natural and critical habitat provided that the detailed BMMP and BOP are fully designed and implemented, in addition to the standard approach to construction mitigation requirements through development, implementation and monitoring of the contractor’s CEMP. There will be residual impacts that can only be addressed through offsetting, and development and implementation of the BOP will be required to address these impacts and to ensure no net loss of biodiversity. In the longer-term, including mitigation and offsetting the Project can meet the biodiversity requirements of the SPS because, after mitigation and offsetting, (i) there are no measurable adverse impacts, or likelihood of such, on the critical habitat which could impair its high biodiversity value or the ability to function, and (ii) the Project is not anticipated to lead to a reduction in the population of any recognized endangered or critically endangered species or a loss in area of the habitat concerned such that the persistence of a viable and representative host ecosystem be compromised.

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452. Approach to residual impacts on forested critical habitat. The Project is estimated to have residual impacts of 59.7 quality hectares on forested critical habitat. These are best compensated by restoration of forest in other areas of the Vaisigano River watershed, with the expectation that a similar suite of species will be conserved through such restoration (restoration should not, therefore, be carried out at considerably higher altitudes).

453. This restoration will also have the side benefit of supporting the flood control efforts of the Project. This may involve reforestation of cleared areas, or enrichment planting, and will also need to include invasive species control. If restoration efforts proceed without invasive species control, it is believed that priority species (at least of the birds, which are better-known than most others) will continue to decline (Rebecca Stirnemann pers. comm. 2019). Conversely, if invasive species control proceeds without restoration, there will be a limited amount of habitat into which successfully breeding species can expand. Priorities for such restoration will be decided after a survey and mapping exercise that identifies restoration areas that would most benefit priority biodiversity, based on criteria such as establishing corridors between forest fragments or enhancing areas currently known to be of value.

454. Priorities for invasive species control are rats and cats (which directly predate priority species), Yellow Crazy Ants (which appear to eradicate Samoa Skink), key invasive plants such as rubber trees (which crowd out native vegetation), and pigs (which otherwise hamper restoration efforts by destroying new plantings). Overall, restoration and invasive species control efforts would be best undertaken in two or three areas – rather than one – to best hedge against failure of any one site, and to offer more potential benefits from varying seasonality of fruit trees at multiple sites.

455. The area of forest requiring restoration will depend on the quality of priority areas chosen for restoration and the appropriate approach (reforestation, enrichment planting, and/or invasive species control) within them. For example, if the approach chosen is to focus on restoration and invasive species control in highly degraded secondary forest (currently c.25% quality), in order to bring it up to the quality of less degraded secondary forest (c.75% quality) there would be a need for this offset to cover c.120 ha (=59.7/(0.75-0.25)). At the other end of the spectrum, an approach focusing on enrichment planting and invasive species control might possibly improve the quality of less degraded secondary forest (c.75% quality) to near natural quality for priority species (~100% quality), and such an offset would thus need to cover c.240 ha (=59.7/(100-0.75)).

456. An important consideration is that, to ensure these actions represent a valid “lasting” offset, their gains must endure for as long as Project impacts (i.e., until any such time as Project dam and reservoir are decommissioned and their footprint restored to at least pre-Project quality). The Project will thus plan and budget for these actions to effectively be carried out in perpetuity. Otherwise, biodiversity gains from – for example – only 20 years of restoration and invasive species control would likely all be lost 10 years later.

457. Costs of forest restoration and invasive species control are very context specific. Fortunately, a relevant publicly available estimate of such costs is available in Bonin (2008). This includes a proposed budget for restoration of native plants and control of invasive plants across c.78 ha at Mount Vaea, on the outskirts of Apia in the lower reaches of the Vaisigano watershed. A five-year program of research, field trials and implementation are estimated to cost at least US$270,000. Considering two restoration offsets for this Project totalling 120-240 ha, restoration of native plants and control of invasive plants might thus cost in the region of US$80,000-170,000/year, although it is anticipated that such costs would reduce over time.

458. Few nationally relevant costs have been published for control of invasive species other than plants. Tye & Butler (2013) state a total cost of c.US$400,000 in an attempt to control of rats across Nu’utele and Nu’ula (totalling 133 ha) in 2009. That project aimed to eradicate rats on islands (with increased logistical costs), needed to capture non-target species at risk of eating rat baits, and included a number of additional biodiversity monitoring programs, so is likely to be considerably more expensive than control of invasive fauna in a similar area of the Vaisigano watershed.

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459. The majority of published costs elsewhere relate to invasive species eradication on islands, rather than control in mainland areas. For mainland control of invasive fauna, costs depend on methods. Trapping is likely to be the most effective method for most invasive fauna in areas >50 ha (Norbury et al. 2014), costing around US$75/ha/year (converted from NZ$) for areas of around 100 ha. Nonetheless, other options will be explored during detailed planning – e.g., mainland control of invasive predators using aerially distributed toxins can cost

460. Control of Yellow Crazy Ants is at an earlier stage of development, but example costs are c.US$890,000/year for control using aerial baits over c.800-2,500 ha of Christmas Island (converted from AU$: PIAT 2019), equating to c.US$540/ha/year. Considering two restoration offsets for this Project totalling 120-240 ha, control of invasive fauna might thus cost c.US$75,000-150,000/year.

461. Species-specific action. The highest priority species for which residual Project impacts are certain is Mao, which has territories overlapped by the Project footprint (Stirnemann & Taylor-Smith 2019). Therefore, in addition to general forest compensation measures, species-specific measures should be considered for this bird. Translocation of some individuals to American Samoa is an approach that offers potentially huge benefits (MNRE 2006; Stirnemann & Taylor-Smith 2019). The species formerly existed on American Samoa but is no longer present. Future survival prospects for the species would be substantially enhanced if it had breeding colonies in two countries, including one (American Samoa) with already well- established methods and resources for invasive species control (R. Stirnemann pers. comm. 2019). The political viability of such a reintroduction could be enhanced by a return reintroduction of the Samoan Swallowtail Butterfly (Papilio godeffroyi) from American Samoa to Samoa, as recommended by Wildland (2019). While acknowledging translocation of Mao would not offer benefits to other biodiversity priorities in the Vaisigano catchment, the Project will budget for – and evaluate the viability of – this action in its No Net Loss/Net Gain strategy. If judged viable, the translocation will at minimum follow guidelines from IUCN/SSC (2013).

462. The cost of such a translocation will be very context- and species specific but can be estimated from experience elsewhere. Acknowledging the context in American Samoa, it is assumed that costs of habitat management, invasive species management and ongoing monitoring would be available from the recipient country. Costs of a translocation program for three bird of prey species to three sites in Ireland were stated to be €1.5 million (Lucey 2014), i.e. US$650,000/species (converted from 2014 Euros), though costs of translocating large, publicly-controversial species in a European country are likely to significantly exceed those of translocating Mao in the Pacific. Costs of reintroduction of a bird of prey to southern England were estimated to be very similar: cUS$700,000 (converted from 2016 GBP: DEFRA 2016). A more relevant example is the cost of translocation of a flycatcher species across islands in the Seychelles – covering site identification, community engagement, personnel costs and physical translocation. This was estimated to be c.US$195,000 (converted from 2013 Euros: Bristol et al. 2014). As such, translocation of Mao is currently estimated at US$250,000, pending more detailed planning and feasibility studies to be undertaken in the development of the BMMP and BOP.

463. Approach to residual impacts on river critical habitat. Project residual impacts on aquatic critical habitat are estimated to be 10.54 Quality Kilometres of river (Section 5.2.2). Offsets for such impacts will need to address the same critical habitat-qualifying species, ideally within the same watershed. Given existing cumulative impacts on aquatic habitats in the watershed, Entura (2019b) proposed an innovative system for restoration of ecological flows from existing infrastructure, which could function as an offset for this Project. A proportion of these ecological flows should already be released under national guidelines (MWH 2009), so only part of the Entura (2019b) proposals are sufficiently additional to qualify as an offset (see below). Here, river stretch lengths have been refined from Entura (2019b) and habitat quality gains have also been quantified, through consultation with William Elvey (in litt. 2019). Entura (2019b) estimated that restoration of ecological flows from Samasoni weir would restore permanent aquatic habitat to the main branch from the Samasoni weir to the Samasoni power station. This 4.2 km stretch is currently highly Modified Habitat (for the purposes of this assessment, perhaps 10% of natural quality), but could be substantially improved by reinstatement of year-round flows (perhaps to 80% of natural quality).

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464. As such, this restoration can be considered to contribute (4.2 × (0.8-0.1)) = 2.94 Quality Kilometres of river critical habitat.

465. Entura (2019b) estimated that restoration of ecological flows from the middle branch weir would not only contribute to improvement of the final 1.5 km of the middle branch (from perhaps 10 to 75% quality), but would also improve the quality of up to 7.9 km of the middle branch upstream of this weir (from perhaps 50 to 90% quality) by allowing access to most migratory species. This can be considered re-establishment of good quality critical habitat, and thus would contribute (1.5 × (0.75-0.1)) + (7.9 × (0.9-0.5)) = 11.41 Quality Kilometres of river critical habitat. Restoration of ecological flows downstream will improve the accessibility of the western branch to migratory species (Entura 2019b), thus improving its overall quality to near natural condition. Considering this 12.3 km stretch at present to be broadly Natural but slightly modified (for the purposes of this assessment, perhaps 75% of natural quality), this improvement can be considered to contribute 12.3 × (0.95-0.75) = 2.46 Quality Kilometres of river critical habitat.

466. Considering all three environmental flow offset benefits discussed above, total benefits to aquatic critical habitat can thus be considered to be 16.81 Quality Kilometres of river critical habitat, far in excess of the predicted 9.9225 Quality Kilometres of residual Project impacts.

467. All of these quality gains cannot, however, be considered “additional” as original project approvals called for minimum flows to be released from historic projects, including the current middle branch weir and Samasoni weir, following MWH (2009). The current requirement following MWH (2009) is 0.2 m3/s from the Samasoni weir and 0.07 m3/s from the middle branch weir. Proposals by Entura (2019b) increase flows from the Samasoni weir (to 0.3 m3/s) and are similar from the middle branch weir (0.06 m3/s; updated per William Elvey in litt. 2019), but also add in requirements for pulse events of higher flows which are critical to maintaining geomorphic processes and simulating natural cues in the ecology of aquatic species (e.g., migration, breeding). It is thus challenging to assess what proportion of the proposals by Entura (2019a) are truly additional. If just 60% additionality is assumed, the 16.81 Quality Kilometres of offset gains is sufficient to compensate for the 10.54 Quality Kilometres of residual Project impacts. Further, the Project aims to also provide indirect compensation benefits for aquatic natural and critical habitat by providing policy and institutional support.

468. There is no direct cost of increasing flows from the Samasoni weir from the current requirement to 0.3 m3/s, but there a cost as a fish ladder (Plate 7.1) and syphon-like structure to encourage fishes to the western branch will be needed to sustain fish passage. Provisional cost of US$50,000.

Plate 7.1: Fish Ladder style that could be adopted at Samasoni weir

Source photo: Lopwell Dam, Portsmouth, Devon, United Kingdom

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469. Approach to residual impacts on river natural habitat. Residual impacts on non-critical aquatic natural habitat are estimated to be 0.82 Quality Kilometres of river. It is anticipated that the middle branch (currently non-critical natural habitat) can be restored to critical habitat through restoration of ecological flows. Apart from this, there is no realistic prospect for improvements to river Natural Habitat in the Vaisigano watershed, since the remaining non-critical natural habitat stretch is the east branch stretch isolated above the Fale ole Fee weir. The residual impact on natural habitat is small, and the Project aims to compensate indirectly for these impacts by providing policy and institutional support.

7.2.7 Updating the EIA, development consent application and bid & contract documentation

470. Finalizing the EIA and development consent. Any issues arising during updating and finalization of the EIA may largely be mitigated and/or managed by: (i) ensuring that good practice is observed in terms of detailed design incorporating recommendations on environmental matters made in the CEAR; (ii) the CEAR being further updated, as required, based on the detailed design and the EMP reflects the updates and changes made during detailed design; (iii) all permits and consents under CSS are applied for and obtained; and (iv) the requirements (conditions) of development consent and any permits and consents and the updated EMP are incorporated into the bid and contract documents. The finalization of the EIA will need to address any comments or concerns raised during the public disclosure period and update the ecological assessment and mitigation sections based on the detailed work form the BMMP and BOP, this will include updating the preliminary cost estimates.

471. The construction supervision consultant (CSC) will support EPC to prepare the development consent application for the Project and this EIA will be reformatted as required as a CEAR and will be submitted in support of that application.

472. Bid and contract documentation requirements. The PMU will ensure that the finalized EIA and its EMP, updated, as required, based on detailed design and incorporated, along with any conditions of project development consent, into the bid and contract documents. The bid and contract documents will also clearly identify the need for the contractor to manage the risks around sourcing and supply of construction materials. This will include undertaking of environmental assessment and applying for development consent and other permits for currently unlicensed sources the contractor chooses to use for the project.

473. As this is a design-build contract, the bid documents will also specify other environmental management requirements such as: (i) all mitigation and management measures identified in the EIA be incorporated into the detailed design; (ii) contractor to engage a suitable qualified environmental specialist to prepare the CEMP and sub-plans; (iii) requirements to comply with applicable standards and the COEP; (iv) the contractor designating a full-time environmental management officer (EMO) and health and safety officer (HSO) and deputy EMO and HSO and recruiting a community liaison officer (CLO) from the local community and the reporting/communication lines and channels; (v) the monitoring and reporting requirements; and (vi) delivery of induction, training and awareness sessions for workers and the community.

474. Prior to any works commencing, including any clearance for surveys and investigations, associated laydown or materials stockpile areas or quarries, the contractor will prepare and submit the CEMP to the PMU, the CEMP will be based on the project EMP and detail the construction methodology and program to be undertaken, identify the risks associated with that construction methodology and detail mitigation measures to avoid or reduce the risks. The CEMP will include site-specific plans, construction methodology for breakwater removal, breakwater reconstruction and all other key elements of the project, sub-plans and the like, prior to any construction activities commencing. The contractor will prepare and submit the CEMP for review and approval. The PMU, CSC and ADB will review and clear the CEMP and advise the supervising engineer that the CEMP may be approved and no objection to commencement of works given.

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475. Once works commence, the EMO and HSO will conduct monitoring of compliance of activities with the approved CEMP and the PMU and CSC will undertake inspections and audits of the effectiveness of the contractor’s implementation of the approved CEMP. The PMU and CSC will devise the checklist to be used for the inspections and audits and will consolidate the inspection/audit findings along with summaries of the contractor’s monthly reporting. ADB will undertake review missions which will report on, inter alia, overall implementation of environmental safeguard requirements.

476. As early as practicable after commencement, the Project will establish the GRM to address concerns and resolve complaints and issues raised on any aspect of project implementation (refer also Section 6). Safeguards concerns will be addressed through the GRM. The CEMP will outline how the contractor will implement the relevant elements of the GRM and how and when they will provide information about construction activities and timing to the community. The contractor will be expected to provide information about the works, impacts and mitigation/control measures to the community in a timely and effective manner. The contractor’s liaison and communication with the community, managed by the CLO, will be guided by the Project’s communications and consultation plan (CCP). Workers and sub-contractors will be inducted to the site and this will include awareness and training on the provisions and requirements of the CEMP and how it is to be implemented.

477. Procurement of consultants and equipment and plant for the project will comply with the prohibited investment activities list in the SPS. The COEP will apply during detailed design, construction and operation and have been referenced as mitigation measures where applicable and tracked through to the EMP.

7.2.8 Identifying suitable material sources

478. Part V of the Planning and Urban Management Act 2004 stipulates that quarry development or operations is required to apply and obtain a development consent from PUMA. Further, COEP 8 contains guidelines specific to quarrying, requiring the contractor to subject the site identification to a public consultation. If required, land acquisition should also comply with the land acquisition and compensation procedure as set out in COEP 4. A quarry management plan (QMP) for each site/source to be used for the project will be prepared and approved, along with obtaining the necessary development consent and permits under the CSS. The QMP will need to be linked with the traffic management plan in terms of haulage routes and controls. The QMP should include:

• A site development and extraction plan that shows the mining area, extent of overburden removal, and location of stockpile areas; • Environmental management facilities such as cut-off drains, and siltation ponds, among other requirements and controls;22 • Mitigation of visual impacts of quarrying, among others; • Health and safety measures, equipment including emergency facilities/equipment; • Protocols and arrangements for blasting (if required); • Designation of a quarry manager; • Guidelines for vegetation removal, including a prior vegetation survey and plan indicating vegetation and trees to be removed, agreed and approved by the PMU; • Overburden stripping and dust suppression; and • Rehabilitation plan.

22 It should be noted that the lack of environmental management was noted during the quarry assessment done by Tonkin and Taylor (2013), particularly the lack of surface water control. As a minimum measure, Tonkin and Taylor recommended the regrading of quarries to develop a suitable fall and a series of surface cut off drains to convey run-off into an excavated sump or sediment control pond where water can percolate through the natural rock fractures.

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479. Mitigation. The measures to mitigate and manage impacts from sourcing of materials include:

• Sources of material (material for the breakwater, gravel, aggregate etc.) and quarry sites for the project will be approved by the PMU and CSC prior to commencement of activities; • Prioritize existing quarry operations and facilitate necessary development consent and permit applications for unlicensed operations; • Prioritize licenced approved quarries with highest ratio between extractive capacity (both in terms of quality) and loss of natural state. Procure materials only from quarries/sites approved by PMU and CSC and with a development consent issued by PUMA; • For each site/operation to be used for the project, the bid and contract documents will specifically require the contractor to develop a QMP as part of the CEMP which addresses the matters identified above; • Select haul routes and times to minimise road congestion and disruption to local communities and do not haul materials during peak traffic periods; • Vehicles transporting materials from an extraction area to the project site, will be covered and secured with tarpaulin to prevent dust or spillage; • Prioritize approved quarries with development consent either closest to the port or to minimise impacts of haulage on communities (i.e. transportation by barge); • For all locally sourced materials (including sand or aggregate), in addition to obtaining development consent and permits, the contractor must obtain an agreement from, including payment of royalties to, the land/resource owner; • Any materials required for the project will only be extracted in accordance with the approved plan (reviewed and cleared by the PMU and CSC in addition to PUMA approvals); and • Reinstate damaged access roads, agricultural land and other properties upon completion of construction works at each section, if damaged due to transport of quarry/borrow materials, other construction materials or any other project related activities.

7.2.9 Biosecurity and introduction of invasive and/or alien species

480. The BMMP and BOP will detail measures required to eliminate existing threats and prevent spread of invasive species within the project site and the areas selected for restoration. In addition, to prevent or reduce other risk of introduction and/or spread of invasive or alien species (flora and fauna), any equipment/plant, vehicles and construction materials (or even food and alcohol brought in for foreign workers) imported to Samoa for the project and the vessels that import them will be subject to clearance procedures under the Quarantine (Biosecurity) Act and may require issue of phytosanitary certificates from Samoa Quarantine Services.

7.2.10 Worker code of conduct

481. The CEMP will detail the protocols to govern workers’ behaviour. The worker code of conduct (WCC) will be discussed and agreed with village leaders and the PMU. The WCC will be adhered to by both expatriate and local workers staff on acceptance / understanding of national cultural differences and governing behaviour relative to: fraternization; conduct in villages; behaviour around women and children; penalties/sanctions on worker use of alcohol and/or drugs; and prevention and reporting of sexual harassment and bullying.

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7.3 Construction Impacts on Physical Environment

7.3.1 Degradation of landscapes and soil erosion

482. Impacts. Observations on site suggest that the impact of invasive species, specifically shallow rooting tree species creates conditions where there are regular landslips. In addition, some areas will be sensitive to soil erosion prior to inundation when surface vegetation is removed, and when this is combined with rain events. Large expanses of open ground (cuttings and embankments) are not visually attractive and can lead to high volumes of silt laden run-off impacting on the existing streams and the aquatic ecology and communities downstream. When undertaking earth works and levelling areas anti-erosive measures should be implemented, and speedy re-cultivation should be followed to stabilise the soil.

483. Mitigation. Borrow pits will be located within the inundation zone, so there will be no visual impact on project implementation.

• The road width and the temporary construction working areas adjacent to the dam site, will require clearing to construct the access roads and working areas, will be clearly demarcated on the ground, using marker posts at regular intervals. The contractor will take measures to ensure the construction works are restricted to the demarcated construction working areas.

• During land clearing operations, topsoil will be collected, preserved, stored using good practice measures, and reused as a base for turfing of embankment slopes or development of barren areas.

• After completion of construction of the dam the landscape shall be restored to a standard that is of equal quality to its original condition. Plant species that are native to the project area shall be used.

• The need for on-site environmental action to preserve landscapes and minimise soil erosion are identified in the EMP section of this EIA. The precise mechanisms will be identified in the CEMP, but contractors will be required to develop and implement the following management plans, which will be approved and monitored during construction by the PMU of EPC and Supervising Engineer: (i) Landscape and Visual Management Plan; (ii) Soil, Erosion and Topsoil Management Plan; and (iii) Waste and Materials Management Plan (particularly with regards to borrow pits).

• Location-specific mitigation measures will be covered by the required plans for these operations, including: (i) Camp Management Plan; (ii) Concrete and Asphalt Production Management Plans; (iii) Construction Plans and Method Statements; and (iv) Method Statements for Temporary Activities.

484. With mitigation in place the post mitigation risk is assessed as low, and in effect is not considered significant.

RISK RISK RISK POST SIGNIFICANT? SEVERITY LIKELIHOOD MITIGATION RISK LEVEL Degradation of landscapes and soil MINOR IMPROBABLE LOW NO erosion

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7.3.2 Soils, geology and hydrogeology

485. Impacts. Soil and water contamination can occur as a result of accidental spillages, such as oil leakage from machinery and stock-piled construction materials and asphalt, oil products and chemicals, penetrating into the soil and/or surface or ground water.

486. The construction process can result in adverse impacts downstream from the dam site, through migration of spilled liquids, silty run-off and oil leakage from poorly maintained mechanical plant or during refuelling. This run-off can enter soils and potentially migrate to groundwater or, via underground flow, to surface water bodies, and adversely affect downstream communities and aquatic ecology.

487. Mitigation. Mitigation is generally in the form of good site practices implemented by the contractor and checked during periodic audit by the supervising engineer. Mitigation measures include using bunds to guide unpolluted water generated upstream from the dam construction works areas, to the downstream unpolluted, silt traps and bunds on the downstream side of the site, together with sumps for settlement before discharge, drip traps and good maintenance of equipment.

488. This will require management by the contractor in the relevant management plans in their CEMP. It has been incorporated into EMP for contractor implementation, which should be secure via their contract. With these mitigation measures adopted by the contractor in the CEMP, impacts can be reduced to an acceptable level. The precise mechanisms will be identified in the CEMP, but contractors will be required to develop and implement the following management plans, which will be approved and monitored during construction by the PMU of EPC (supported by the CSC) and Supervising Engineer:

• Water Resources Management Plan, including: o Ground Water Management o Wastewater Management • Emergency Response Plan, including: o Spill Management Plan • Waste and Materials Management Plan (WMMP), including: o Spoil Disposal Plan o Asbestos Management Plan • Soil, Erosion and Topsoil Management Plan

489. Additionally, location specific mitigation measures will be covered by the required plans for these operations, including: (i) Camp Management Plan; (ii) Concrete and Asphalt Production Management Plans; (iii) Construction plans and Method Statements; and (iv) Method Statements for Temporary Activities.

490. Landslide and erosion impacts are covered in natural hazards.

491. With mitigation in place the post mitigation risk matrix is assessed as “low”, and the effect is not considered significant.

RISK RISK RISK POST SIGNIFICANT? SEVERITY LIKELIHOOD MITIGATION RISK LEVEL Pollution of soils, geology and MINOR POSSIBLE LOW NO hydrogeology by construction runoff and accidental spills

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7.3.3 Climate change – reservoir GHG emissions

492. Introduction. The draft procedure proposed by the Climate Bonds Initiative for the assessment of mitigation components for hydropower assets for certification (Climate Bonds Initiative 201923) was followed in this assessment of reservoir greenhouse gas emissions. This procedure is similar to the International Hydropower Association’s Hydropower Sustainability Assessment Protocol (IHA 2019) for the assessment of the climate mitigation of hydropower projects.

493. The Climate Bonds Initiative procedure flow chart (Figure 7.2) shows the steps taken to satisfy the mitigation test for greenhouse gas emissions. Reference in the flow-chart to the next step [the A&R (Adaptation and Resilience) test] refers to the more detailed assessment to assess climate adaptation and resilience is not assessed here.

Figure 7.2: Decision tree if a facility passes or fails mitigation component of Climate Bonds Initiative

Source: Climate Bonds Initiative 2019

494. The first step in the mitigation test is a greenhouse gas (GHG) predictive screen. This estimates the power density of a hydropower project (i.e. the energy production per unit area inundated – W/m2). A power density measurement greater than 5 W/m2 requires no further assessment, however if it is lower, a reservoir GHG Assessment using an accepted method should be undertaken.

495. If the subsequent reservoir GHG Assessment estimates a reservoir emissions intensity less than 100 gCO2e/kWh, this is considered acceptable to have passed the mitigation test. However, a reservoir emissions intensity greater than 100 gCO2e/kWh may require further on-site assessment.

23 Climate Bonds Initiative (2019). Hydropower Criteria: The Hydropower Criteria for the Climate Bonds Standard and Certification Scheme. Draft for Public Discussion.

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496. Power density. The power density of the scheme is determined as being 1.8 W/ m2 and is below the predictive screen level of 5 W/m2 (Table 7.7). Therefore, it is necessary to undertake the GHG emissions assessment for this project.

Table 7.7: Power density calculation for Alaoa Multi-purpose Dam

Power density calculation Total Installed Capacity (MW) 0.4 Inundated Area at FSL (ha) 22 Power Density (W/m2) 1.8

497. Greenhouse gas emissions assessment. As the power density of the hydropower system is low, a greenhouse gas emissions assessment was undertaken. A Tier 1 quantitative estimate of net reservoir GHG emissions was undertaken using the World Bank method (Liden 2013). All data and assumptions utilised in this assessment are provided in Appendix 4. There is a degree of uncertainty due to the assumptions involved, however the outcome is well below the 100 gCO2e/kWh screen, and is therefore considered acceptable i.e. to have passed the mitigation test.

498. This method estimates carbon stocks in the 22ha inundation area, utilising published carbon estimates (IPCC 2006, 2019) and knowledge of the area to apply the most applicable carbon estimates for the location. Further steps and assumptions in the estimate included:

• Assumption that 50% of estimated carbon is available for decomposition (and hence emission)

• Estimate that 7% of carbon will be emitted as methane (CH4) and the remainder as carbon dioxide (CO2)

• Application of empirical factors to determine C emitted by both CO2 or CH4 • Application of a conversion factor of 25 to convert CH4 to CO2 equivalents • Establishing annual average emissions from the reservoir based on a 100-year reservoir life.

499. In addition to the estimate of gross emissions from the new reservoir, current annual CO2 sinks (i.e. vegetation growth) and emissions (i.e. from current river/s) were estimated and accounted to provide a net GHG emissions estimate of 64.4 tonnes CO2 equiv/y.

500. The reservoir emissions intensity estimate for the Alaoa reservoir (based on the emissions estimate and annual generation of 2.12 GWh) is 30.35 gCO2e/kWh. Overall reservoir emissions of the project appear to be low and the emissions intensity assessment for hydropower assessment estimate is substantially below 100 gCO2e/kWh. This would indicate that based on this Tier 1 GHG reservoir Assessment, the Alaoa reservoir fulfils the Climate Bonds Initiative (2019) Low GHG Compatibility Test for hydropower.24

24 A further emissions estimate using a different method (e.g. GRes tool) may be undertaken if required to obtain another estimate of emissions. Use of the GRes tool requires assessment by an IHA certified assessor and external verification by an expert panel to confirm the correct application of the tool.

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7.3.4 Climate change – adaptation and resilience of the Project

501. ADB (2013) identifies building new storage reservoirs and installing new turbines as engineering adaptation options for climate proofing the energy sector. Building new water storage reservoirs is also a climate change adaptation option for the water sector (ADB, 2013), and building flood mitigation dams is an adaptation option for increases in flooding due to climate change. Alaoa multipurpose dam has the potential to provide climate change adaptation for the energy and water sectors, and for flooding in Apia. The ability of the dam to mitigate climate change impacts on water supply and flooding is explored in the following sections.

502. Water supply. The impact of climate change on water supply security was investigated by running the catchment model with no dam in place. The mitigation provided by the dam was then explored by running the model with the dam in place. Results are shown in Table 16.7 for the historic climate and the median climate change cases.

503. The model results show that the projected median change in river flows due to climate change will decrease water supply security without the dam in place, from 3.2% to 6.4% of days where the water supply requirement is unable to be met. With the dam in place, the climate change impact is mitigated, with 0.8% of days where water supply requirement is unable to be met. This shows that the dam provides climate change adaptation for water supply.

Table 7.8: Water supply reliability over 50-year model run

Scenario Percent days with no supply Days no supply No dam Historic 3.2 592 Median future climate 6.3 1174 With dam Historic 0.3 51 Median future climate 0.8 141

504. The model was also run to investigate the increase in storage required to give 100% water supply reliability under median future climate conditions. This showed that the NMOL would need to be raised by 14.7m to 167.0m to provide 100% water supply security. To provide the same water supply security with the dam under historic climate (0.3% failure rate) would require the NMOL to be raised to 157.8m, an increase of 5.5m.

505. Flood mitigation. To investigate the ability of Alaoa dam to mitigate climate change impacts on floods, the flood model was run with and without the dam in place, for historic and future climates. The flood mitigation provided by the dam for Samasoni and Lower Vaisigano was investigated. Table 7.9 shows the results of the model runs as peak flow for a given annual exceedance probability (AEP) of the inflow flood to the dam. The results show that the peak flows at Samasoni and Lower Vaisigano are increased under modelled climate change scenario without the dam in place. The dam mitigates the impact of climate change by reducing peak flows downstream over the range of AEPs modelled.

Table 7.9: Peak flows, in m3/s, at Samasoni and Vaisigano under dam and no dam conditions for historic and future climate

No Dam With Dam Inflow Historic Future climate Historic Future climate AEP Lower Lower Lower Lower (1 in X) Samasoni Vaisigano Samasoni Vaisigano Samasoni Vaisigano Samasoni Vaisigano 10 237 298 269 338 145 210 163 235

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20 367 459 415 520 218 315 244 354 50 614 772 692 870 356 522 396 582 100 876 1100 989 1235 545 730 686 811 150 1017 1269 1146 1421 701 833 858 985 200 1132 1405 1272 1572 835 945 1010 1179 500 1470 1820 1634 2024 1301 1576 1502 1863

506. The shifts in AEP for flood peaks at Lower Vaisigano are shown in Table 16.9 for no dam and dam cases, and historic and climate change scenarios. This shows that the 1 in 20 AEP-flood under current conditions would become a 1 in 17 AEP flood under projected future climate, reducing the effectiveness of the flood protection walls at Apia. With the dam in place, the level of flood protection is improved when compared with the historic climate case, and the flood protection walls at Apia would provide protection up to a 1 in 26 AEP-flood.

507. The flood mitigation provided by the dam under future climate conditions is evidenced by the reduction in frequency (increased AEP) of flood events modelled. For example, the current 1 in 100 AEP flood-event would become a 1 in 78 AEP-event under the projected future climate conditions with no dam. With the dam in place, this becomes a 1 in 134 AEP -event under future climate.

Table 7.10: AEP (1 in X) of flood peak at Lower Vaisigano under dam and no dam conditions for historic and projected future climate

Historic climate no dam Future climate no dam Historic climate with dam Future climate with dam 10 8 18 12 20 17 43 26 50 39 122 70 100 78 245 134 150 110 326 197 200 144 398 282

508. Damage mitigation. The flood mitigation provided by the dam under climate change conditions was assessed in terms of reduction in annual damages at Apia, using the method described earlier. This was investigated using the shift in AEP of flood events at Vaisigano. For the purposes of the damages assessment, this was taken as the equivalent AEP of the flood peak under current conditions, for the given event and scenario. For example, from Table 16.8, a flood peak of 315 results from a 1:20 AEP inflow flood, with dam under historic climate. This is equivalent to a 1 in 11 AEP-flood under current conditions (historic climate, no dam). The equivalent AEPs at Lower Vaisigano are shown in Table 7.11.

Table 7.11 Equivalent AEP (1 in X) of flood peak at Lower Vaisigano under current conditions

Historic climate No dam Future climate No dam Historic climate with dam Future climate with dam (current conditions) 1.01 1.1 0.6 0.8 2 2.3 1.2 1.7 5 6 2.9 4 10 12 6 6

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20 25 11 14 50 61 25 30 100 139 46 53 150 209 58 79 200 291 72 122

509. Using the method outlined earlier, this gives the damage estimates shown in Table 7.11. Without the dam in place, the increased annual damage at Apia due to the impact of climate change on flooding would be US$ 1,453,734 in 2010. Two adjustments were made to this figure, one for population growth in the Apia region (0.755% increase per annum) and one for property value increase based on the overall economic growth rate (2% per annum since 2016). This gives an annual increase in damages of US$1,724,716 in 2018 due to increase in flooding as a result of climate change.

510. With the dam, the impacts of future climate are mitigated, resulting in a reduction in annual damages of approximately US$2,760,576 in 2010, compared to future climate with no dam. This gives an annual expected benefit to Apia of the multi-purpose dam due to the flood retention function, under a future climate scenario, of US$3,275,158 in 2018. This demonstrates that the dam will in fact create even more value due to flood protection of Apia for a future climate change scenario (i.e. US$3.275m with climate change compared to US$2.873m without climate change in 2018 dollars).

Table 7.12: Damages at Apia due to flooding (USD)

Reduction in AEP Historic climate Future climate no Historic climate Future climate damages due to (current no dam dam with dam with dam dam, future conditions) climate. 1.01 $8,895,420 $8,956,140 $8,463,003 $8,771,295 $184,845 2 $9,199,118 $9,376,866 $8,981,212 $9,153,687 $223,179 5 $10,110,212 $11,259,716 $9,664,213 $9,900,523 $1,359,192 10 $13,536,403 $15,820,531 $10,924,857 $12,813,522 $3,007,009 20 $20,388,786 $28,515,799 $14,782,291 $17,093,636 $11,422,163 50 $45,259,918 $59,976,874 $28,679,163 $33,942,023 $26,034,852 100 $86,711,805 $98,256,255 $43,818,113 $49,784,928 $48,471,327 150 $100,529,101 $108,339,151 $56,694,921 $75,795,914 $32,543,237 200 $107,437,749 $113,904,479 $68,088,493 $94,278,722 $19,625,757

511. Other adaptation measures. Climate change adaptation measures associated with the dam arrangement and operation can also be considered in the project implementation. These include:

• Improved hydrological forecasting techniques and adaptive management operating rules. It is recommended that river and rainfall monitoring stations are installed within the dam catchment and the reservoir, and that these are telemetered to allow operators access to real-time data. Ideally, a catchment model coupled with a storage model would be used to forecast inflows to the storage and the resulting lake levels. This can be used to optimise operation in the event of large inflow events to maximise water storage and minimise downstream spill as far as possible. Optimised reservoir management can improve energy output and water supply security by adapting to changes in rainfall or river flow patterns. The hydrologic data can also inform emergency response in the event of a flood.

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• Development of basin-wide management strategies that take into account the full range of environmental and human water uses. This includes restoring and improving management of upstream land including afforestation to reduce floods, erosion, silting, and mudslides. This is being investigated as part of the environmental and social studies for the dam.

512. Increased sedimentation due to increased frequency of large rainfall events has been allowed for in the project design by inclusion of the low-level outlet to enable sluicing of the sediment from the dam storage. The frequency of operation of this outlet should be investigated as part of the operating rules and procedures.

7.3.5 Natural hazards

513. Seismic conditions - impacts. The dam is located in region that is seismically active the dam and structures in this area have the potential to be vulnerable to these natural hazards.

514. The dam will be designed for an AEP of 1 in 10,000-year earthquake, which is typical based on international standards for a High hazard dam. The values for the PGA that the dam and the appurtenant structures will be taken from the site-specific seismic hazard assessment report undertaken by GNS Science for the Fuluasou Dam in Samoa. The 1 in 10,000-year PGA given in this report is 0.37g.

515. Mitigation. To mitigate this potential vulnerability, the dam and associated structures have been designed Seismic loading with PGA for MDE (maximum design earthquake) has been adopted, which is equivalent to 1:10,000 AEP earthquake event (Entura Technical Report - Chapter 9 Seismic hazard and loading), to ensure the dam and associated structures are able to withstand seismic activity of this scale.

516. Specific design features have been incorporated into the design to mitigate seismic hazards.

RISK RISK RISK LIKELIHOOD POST MITIGATION SIGNIFICANT? SEVERITY RISK LEVEL Natural Hazards – MAJOR IMPROBABLE MEDIUM NO Seismic Hazards

517. Landslides, mudslides and floods - impacts. As bedrock is exposed in the riverbed and also in the abutments and no long persistence joints have been noticed hence small wedge failure may occur around the rim. While it is expected that during impounding of the reservoir initial sloughing of the superficial overburden material will take place no major landslide are expected (Final Technical Feasibility Report – Section 8.3.2 Entura 2019).

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7.3.6 Air quality – dust and other emissions

518. Impacts. Adverse air quality impacts can occur due to: emission of inorganic dust from digging / loading works; emission of harmful substances; dust from combustion of diesel used by transportation vehicles and manufacturing machinery (crushers / concrete batching plants). Welding works cause welding aerosol and manganese monoxide emissions.

519. The dam will follow a RCC technique requiring cement and could potentially result in cement dust emissions. Dust arising from construction works has potential to have negative impact on the ambient air quality, and it is necessary to take effective protective measures to minimize the negative impact, especially near settlements

520. During construction, air pollution in the form of dust from earthworks and vehicle emissions will increase. Deterioration of air quality during pre-construction and construction works can be due to the following: (i) dust emissions during earthwork and from stockpiles; (ii) dust from loading, transportation and unloading of soil and other friable materials; (iii) emissions from operation of construction machinery, crushing plant, concrete batching plant, etc.; and (iv) dust and emissions from onsite and offsite traffic, vehicles moving across unpaved or dusty surfaces.

521. Dust is a problem for a variety of reasons, including:

• Inconvenience to local people, including re-wash of laundry put outdoors to dry, re-wash of windows, curtains and vehicles. Dust can contaminate food left in the open air in homes and shops and be ingested during meals. • Health and safety. Dust may affect health by irritating eyes and worsening the health of people with bronchial conditions (e.g. asthma). Dust can reduce visibility for drivers on roads, creating a road safety issue. • Crop damage. Even low concentrations of dust can affect plant and fruit growth. Plant growth is particularly susceptible to dusts that are highly alkaline, for example limestone and cement dust. Dust deposited during light rainfall can cause the soil surface to form a crust increasing run-off. • Impact on ecology. Dust blowing onto watercourses may damage ecology by increasing sedimentation, reducing sunlight and suffocating marine fauna. It may also affect plant growth and change the species of plants growing in an area. • Impacts to businesses. Bee keeping and selling local produce are noted as an economic activity within the Project area. • Damage to plant and equipment. Within the construction site, dust can cause mechanical or electrical problems in sensitive equipment, such as computers. It can also increase abrasion of moving parts in equipment and clogging of air filters.

522. The amounts of vehicle-emitted pollutants will depend on the technical condition of the contractor’s vehicles, fuel quality and travel speed. Older vehicles usually have lower fuel consumption efficiency and cause higher emissions of combustion by-products. Increasing speed of the vehicle demands higher fuel supply and therefore results in larger amounts of emitted pollutants. The contractor should pay attention to the age and status of technical maintenance of vehicles/machinery used during construction.

523. There are no industrial sources of air pollution in the area and there is very little vehicular traffic in the area.

524. The scale of dust and exhaust emissions related impacts will depend on the prevailing wind direction in the Project area, traffic speed and the status of technical maintenance of the vehicles/machinery and organization of works.

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525. The location of the construction camp and laydown sites (including topsoil, spoil disposal areas) is not confirmed though a location within the inundation zone, behind the dam is preferred and will be remote from any residential uses. The location, layout and technical parameters of the camp will be defined by the contractor in a Camp Management Plan. While areas have been identified by the Design team the final locations of the temporary (camp, laydown areas) any permanent (spoil disposal) sites will be identified and specified by the contractor with consideration of the recommendations provided in this EIA, including development and implementation of all plans and sub-plans required by the EMP and included in the contractor CEMP. Locations will be agreed and approved by EPC.

526. There are areas of residential development along the access road alignment. At these points an adverse air quality impact from construction activity is possible, though the intensity of activity will be very low. For this reason, the consequence of construction air quality impact is considered to be “medium” and the likelihood of impact “probable”, in the absence of mitigation. Adverse impact is therefore anticipated and will require management by the contractor in the form of an air quality (emissions and dust) management plan included in their CEMP and identified in the EMP / contract for contractor implementation.

527. Mitigation. Dust-suppression measures aimed at prevention of air pollution will include watering of construction access roads, site roads and construction sites. Regular water sprinkling and enforcement of reasonable vehicle speeds during construction will alleviate dust impacts. The capacity of available water supplies will need to be checked to confirm sufficient water is available for watering, and that existing supplies used by downstream users will not be adversely affected. It will also need to comply with the measures in the Water Management Plan. Dust at construction sites will be minimised by using closed / covered trucks for transportation of construction materials (especially loose construction materials such as gravel, sand, soil, etc.) and debris.

528. Other measures planned to maintain good air quality include locating crushing plants, concrete mixing sites and stockpiles at least 1 km from sensitive receptors, as well as confining working vehicles to designated routes away from sensitive receptors. Stockpiles will be covered or dampened if local conditions (e.g. strong winds) give rise to significant dust emissions. All plant will be maintained in good working order, including any dust suppression / collection equipment (filters, etc.) that is fitted.

529. Prior to commencement of works likely emissions from crushers, concrete production facilities and other emissions generating facilities must be determined and agreed with the EPC.

530. The contractor will develop an Air Quality Management Plan. The plan shall provide details of mitigation measures, specific location, and schedule where such measures shall be implemented. This is required to minimise impacts to sensitive receptors due to: the presence of the camp, construction works, sourcing and transport of construction materials, and other project-related activities. Recommendations provided in this EIA should be included in the plan.

531. The general requirements for air quality mitigation are identified in the EMP section of this EIA. The precise mechanisms will be identified in the CEMP, but will include the following management plans:

• Air Quality Management Plan • Waste and Materials Management Plan • Traffic Management Plan • Blasting Management Plan

532. Additionally, location specific mitigation measures will be covered by the required plans for these operations, including: (i) Camp Management Plan; (ii) Concrete Production Management Plans; (iii) Construction Plans and Method Statements; and (iv) Method Statements for Temporary Activities.

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533. These method statements will include sections relating to the management of air quality, including dust control. The method statements shall be reviewed by the contractors Environmental Officer before submittal to the Supervising Engineer for review and approval. All method statements must be prepared and approved before any works can start in the planned areas. The method statements shall also include a record of consultations undertaken with all neighbouring land users including their agreements for the use of these areas.

534. The post mitigation risk is assessed as “low”, and the effect is not considered significant.

RISK RISK RISK POST SIGNIFICANT? SEVERITY LIKELIHOOD MITIGATION RISK LEVEL Dust and other emissions to air MINOR IMPROBABLE LOW NO (assuming good (assuming site practises) good site practises)

7.3.7 Hydrology and water quality

535. Impacts. Water will be required for construction activities, including water required for: construction (e.g. concrete mixing); dust suppression; cleaning equipment; potable water for construction workers; and use in construction camps. If water resources are not managed appropriately by contractors during construction, there is potential for depletion of the resource and adverse impacts on water availability for the local community downstream, including for potable supply extracted at the Samasoni weir.

536. Water resources are at risk of contamination during construction, due to accidental spillage of construction liquids and materials, from activities (e.g. refuelling), poorly maintained mechanical plant or poor storage of liquids. There is also the risk of deposition of airborne contaminants, and other contaminants being mobilised in surface water runoff, and being washed into watercourses, with adverse effects on downstream communities and aquatic ecology.

537. There is a potential risk of contamination due to sewage treatment facilities at construction camps. This risk will be managed by either treating the sewage to the required standards, prior to discharge of treated wastewater to surface watercourses, or the collection of sewage in septic tanks, and it disposal by licenced sewage disposal companies. This will require appropriate management and monitoring to ensure that discharges are within acceptable levels, based on permit requirements and Samoan / international standards.

538. There is a risk that the construction activities could result in the pollution of watercourses that may be used by the community, and have adverse impacts on stream ecology, if not appropriately managed. This will require management by the contractor.

539. Mitigation. The contractor will prepare a Water Resources Management Plan, that must provide details on predicted wastewater (sewage) volumes, disposal scheme, information on capacity and type of wastewater treatment facility, location of the discharge point/points with indication of coordinates. A discharge permit will be sought from the MNRE and maximum allowable discharge limits (MADL) will be set which the project must then comply with. The plan should include measures to minimise water usage in the first instance, and also opportunities for reuse of water where possible.

540. The contractor will undertake a capacity study of available water resources along the alignment, including the location and quality of water resources used by villages, to identify the capacity of resources. with the contractor must assess the availability and current usage of current supplies, to avoid any impact on the availability of resource to communities and businesses along the alignment.

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541. If existing groundwater or surface water resources are not appropriate (quantity or quality), alternative sources of water will be identified by the contractor, to ensure the available resources used by the local communities are maintained at all times. The contractor will liaise with the community to understand seasonal water demand constraints, and periods of highwater volumes / increased erosion.

542. Water abstraction should also be designed in accordance with the requirements of the Biodiversity Management Plan to minimise impacts to habitats reliant upon surface and ground water.

543. The potential pollution impacts will be mitigated through the implementation of good site practices by the contractor, checked during regular audits by the supervising engineer. This will include: material storage and spill prevention measures set out in the Water Resources Management Plan and Emergency Response Plan, respectively,

544. All camp sewage treatment plants must be managed in accordance with manufacturer’s instructions by competent personnel, and discharges regularly monitored. If discharges cannot be treated to an acceptable standard, liquid wastes must be removed by an authorised company and disposed in an environmentally responsible manner in accordance with the Waste and Materials Management Plan.

545. The potential risk of construction activities resulting in increased flood risk, of being adversely effects by flooding will be managed though measures set out in the Water Resources Management Plan.

546. This will require management by the contractor in the form of a management plan in their CEMP and needs to be incorporated into EMP / contract for contractor implementation. Provided these mitigation measures are adopted by the contractor in the CEMP, the impacts can be reduced to an acceptable level. The precise mechanisms will be identified in the CEMP, but contractors will be required to develop and implement the following management plans, which will be approved and monitored during construction by the PMU, CSC and Supervising Engineer:

• Water Resources Management Plan, including: Ground Water Management and Wastewater Management • Emergency Response Plan, including: Spill Management Plan • Waste and Materials Management Plan

547. Additionally, location specific mitigation measures will be covered by the required plans for these operations, including: (i) Camp Management Plan; (ii) Concrete Production Management Plans; (iii) Construction Plans and Method Statements; and (iv) Method Statements for Temporary Activities

548. The post mitigation risk is assessed as “low” and the effect is not considered significant

RISK RISK RISK POST SIGNIFICANT? SEVERITY LIKELIHOOD MITIGATION RISK LEVEL Adverse impacts on water quality and MINOR POSSIBLE LOW NO quantity, and flood risk, due to (assuming good (manageable construction activities site practises) assuming good site practises)

7.3.8 Borrow pits and quarry sites

549. Environmental impacts associated with the operation of borrow areas include: noise and dust impact, silty runoff and loss of habitat. However, for this project, the quarry site will be located behind the dam site within the inundated area and the quarry is remote from sensitive receivers.

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550. Mitigation. The contractor shall obtain all development consents as required and develop a Quarry Management Plan as part of the CEMP. This will form part of the Waste and Materials Management Plan. The Quarry Management Plan must be developed in association with a biodiversity specialist and the Forestry Department.

551. With mitigation measures in place the risk is assessed as “low” and the effect is considered not significant.

RISK RISK SEVERITY RISK RISK SIGNIFICANT? LIKELIHOOD LEVEL Site specific impacts – quarry MAJOR POSSIBLE LOW NO development

7.3.9 Waste and Materials

552. Impacts. The construction phase of the project will generate wastes including the following anticipated waste streams:

• Green waste will be generated during site clearance; • Wastewater treatment sludges from operation of camp sewage treatment plants. If wastewater from these plants does not meet acceptable discharge standards, this may also become classified as a waste; • Hazardous wastes, including oils, lubricants, oil filters, absorbents and rages, paints / solvents, and batteries. • Soil polluted with petroleum hydrocarbons from fuel / oil spills or leaks; • Tyres; • Scrap metal; • Potentially recyclable materials (cardboard, plastics, etc.); and • Mixed municipal wastes from construction camps and worksites.

553. The estimated quantity / volume of the key waste streams, based on experience from similar projects, is presented in Table 7.13.

554. The amount of domestic waste will depend on the number of the staff (a staff level of 100 has been assumed in this ESIA based on information from other projects). Assuming that the quantity of domestic waste generated per capita per year totals 0.7 m3, the approximate total amount of domestic refuse produced during construction will equate 100 x 0.7=70 m3/year for the construction camp.

555. Poorly managed solid and / or liquid waste can result in contamination impacts on the water environment and soil, leading to impact on flora and fauna and health risks to local residents.

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Table 7.13: Description of construction waste material and approximate volumes of waste

Approximate Waste material Description Characteristics quantity Waste paints that may contain organic solvents or other liquid 1,650 -2,000 kg hazardous substances H3B – ignitable; Oils and oily lubricants liquid 120-150 kg H5 – harmful Absorbents, overalls and rugs, contaminated with hazardous Solid 50-70 kg matter Waste tyres Solid 3,000 -3,500 kg - Oil filters Solid 20-25 kg H5 – harmful Brakes and other materials Solid 50- 70 kg H7 - Carcinogens that contain asbestos25 Lead containing batteries Solid 360-450 kg H6 - Toxic Metals (various) Solid 500- 1,000 kg - Mixed municipal waste Solid 225 kg -

556. Mitigation. The contractor will prepare a Waste and Materials Management Plan to ensure the impact of waste disposal and the use of materials in reduced to an acceptable level. The precise mechanisms will be identified in the CESMP, but contractors will be required to develop and implement the following management plans, which will be approved and monitored during construction by the PIURR and Supervising Engineer:

• Waste and Materials Management Plan • Water Resources Management Plan, including: Ground Water Management and Wastewater Management

557. The Waste and Materials Management Plan requires the adherence to the waste hierarchy26 to prevent or reduce the generation of waste where possible, and then to reuse / recycle wastes where possible, in preference to disposal. Agreements / contracts will be signed and maintained with the appropriate authority authorised company to ensure timely transportation and disposal of waste. contractors will be responsible for maintaining these contracts and ensuring that all wastes are disposed in an environmentally responsible manner in accordance with the Waste and Materials Management Plan and Samoan regulations. The contractor shall audit waste disposal companies used to dispose of wastes from the Project.

558. The Camp Management Plan shall set out measures to manage camp sewage, and domestic waste.

559. There are no waste disposal facilities for hazardous wastes present in the project area, and there is limited provision for the management of hazardous waste disposal in Samoa, so this category of waste must be handed over to an authorised contractor for disposal. Any hazardous waste agreement with a company authorised for treatment (deactivation, incineration) or re-use in other technological processes must be signed and made available to the Engineer for approval. Treatment, utilisation, disposal of waste shall be carried out only by authorised contractors.

25 Asbestos containing brakes and construction materials should be avoided on site 26 Waste prevention → Reuse → Recycling → Other recovery → Disposal

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560. The area allocated for temporary storage of hazardous waste shall have special preventive measures implemented, in particular, containers shall have secondary containment and no mixing of hazardous waste with any other waste shall be allowed. Hazardous waste containers shall be checked for tightness. The staff involved in hazardous waste management shall be trained in waste management and safety issues.

561. If there are no suitable disposal options available for hazardous waste, then there may be a need to manage this waste on-site, though interment in lined pits. However, this is not a recommended option and would only be used if all other options were unfeasible. In this case, any proposed location will require adequate environmental assessment, design and management. Any approach must be designed, reported in the CEMP and approved before any construction work commences.

562. While the waste impacts could be considered undesirable the risk severity is considered to be “moderate” and the likelihood of the event happening “possible’ The risk matrix suggests a risk level of “medium” – needs to be incorporated into ESMP / contract for contractor implementation.

563. The post mitigation risk is assessed as “low”, and the effect is not considered significant.

RISK RISK SEVERITY RISK POST SIGNIFICANT? LIKELIHOOD MITIGATION RISK LEVEL Impacts due to the use of MINOR IMPROBABLE LOW NO materials or the disposal of construction waste

7.4 Construction Impacts on Biological Environment

7.4.1 Biodiversity - potential impacts on critical and natural habitat

564. This assessment follows good practice impact assessment methodology used for a project involving aquatic and terrestrial impacts (MRDI 2019). Following this methodology, pre-mitigation impacts on natural and critical habitat (Table 5.13) are assessed in Table 7.1 and discussed in Sections 7.2.1 – 7.2.6.

565. As noted in Section 7.2.5 and 7.2.6, a BMMP and BOP will be developed which will detail measures required to mitigate and/or offset the impacts on biodiversity. These will be available for implementation ahead of construction award to allow as long a period as possible for some measures (such as endemic tree and shrub nursery establishment) to be underway.

7.4.2 Vegetation removal and forest clearance during construction

566. Impacts. The contractor will be required to clear vegetation for construction site access, working areas and for the reservoir area.

567. Mitigation. The contractor will prepare a forest clearance plan (FCP) as part of the CEMP, this will identify the trees to be removed and any specimen/mature trees that can be protected identified and marked on the ground and identified on a site drawing. Excavator drivers will be made familiar with the plan and marked up site plan/drawing prior to activities each day. As relevant, the FCP will be aligned with the BMMP and BOP. The FCP will be prepared, reviewed and approved prior to any clearance activities being undertaken (including clearance for surveys or investigations).

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7.5 Construction Impacts on Socio-economic Environment

7.5.1 Labour conditions

568. Impact. A lack of appropriate human resources policies and procedures by the contractor could lead to workers unfavourably interacting with the local community, or conversely being unfairly treated and dismissed by the contractor. While influx impact will be low as the proximity of the site to Apia makes it very likely that semi-skilled and unskilled labour will be sourced locally, there will still be need for members of the detailed design team, management, engineering and supervisors creating influx. These numbers will be small and likely can be accommodated within the existing urban area.

569. Mitigation. The precise mechanisms for the management of labour conditions will be identified in the CEMP, but contractors will be required to develop and implement the following management plans, which will be approved and monitored during construction by the PMU and Supervising Engineer:

• Labour and Working Conditions Management Plan • Local Employment and Procurement Plan (LEPP) • Social Risk Register • Worker code of conduct (WCC) • Grievance Redress Mechanisms (GRM) • Camp Management Plan

570. The contractor will be responsible for ensuring that site working conditions and those adopted by sub-contractors (including working terms, wages, equal opportunities, benefits, GRM, accommodation provision, etc) comply with Samoan and ADB requirements.

571. The contractor will be required to prepare a code of conduct that enshrines the commitment of the project to meet employment and labour standards. Environmental and social protection and anti-bribery and corruption controls. Requirements and training to manage the behaviour of construction workers. Labor and worker conditions policies and procedures will be developed and implemented as required under the CEMP.

572. The post mitigation risk is assessed as “low” and the effect is considered to be not significant, following the implementation of the proposed ongoing mitigation.

RISK RISK SEVERITY RISK RISK LEVEL SIGNIFICANT? LIKELIHOOD Inadequate labour conditions MODERATE POSSIBLE LOW NO

7.5.2 Workplace and Community Health and Safety

573. Impacts. Construction activities are inherently hazardous, due to the activities they involve, and the constantly changing nature of operations, work locations and site conditions. The large size of this work site present an additional risk factor. Risks to safety can occur due to violation of proper health and safety practices and may lead to injuries and accidents.

574. Risks from construction activities apply to both to Project personnel and the community in the areas near the Project. Hazards associated with construction activities include:

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• Construction traffic and mobile work equipment; • Lifting operations; • Interaction between vehicles and pedestrians; • Deep excavations; • Temporary works; • Work at height, particularly on temporary access structures; • Exposure to noise, dust, vibration and other hazardous agents; • Hazardous materials, including fuels and bitumen; • Exposure to heat, cold and extreme weather conditions; • Electrical and other equipment; and • Unauthorised access – a particular hazard in work sites spread over a large area.

575. Additionally, the remote location of the work site presents an additional risk factor, as assistance would take longer to arrive in the event of a medical or other emergency.

576. Though unlikely, the implementation of the project may result in impacts on the health and safety of the community as a result of: noise, dust and other emissions from earthmoving and operation of equipment and vehicles.

577. Failure to implement robust safety procedures and develop a positive safety culture could lead to injury and illness and therefore health and safety will require robust management by though the contractor though the measures in the Health and Safety Management Plan.

578. Mitigation. Safety impacts will require management by the contractor in the form of a management plan in their CEMP and needs to be incorporated into EMP / contract for contractor implementation. The precise mechanisms will be identified in the CEMP, but contractors will be required to develop and implement the following management plans, which will be approved and monitored during construction by the PMU and CSC:

• Health and Safety Plan based on risk assessment undertaken for specific activities and jobs, job safety analysis, and covering on-site and off-site (including need for contractor to engage an approved service provider to deliver communicable diseases awareness and prevention training to workers and adjacent communities); • Emergency Response Plan, covering evacuation procedures, non-emergency critical situations and including: Natural Disaster Response Plan and Spill Management Plan.

579. Additionally, location specific mitigation measures will be covered by the required plans for these operations, including: (i) Camp Management Plan; (ii) Concrete and Asphalt Production Management Plans; (iii) Construction Plans and Method Statements; (iv) Method Statements for Temporary Activities.

580. Implementation will be enforced by suitable qualified H&S personnel and by robust monitoring of the required measures. On-site support from an international consultant specialising in health and safety, providing additional technical support and advice, and building the capacity of the contractor will be engaged. The consultants will assist the contractors in developing, implementing and monitoring the Health and Safety Plan.

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581. The Emergency Response Plan will include measures and resources for prevention, mitigation and response to all foreseeable emergency scenarios (road traffic accidents, spills, fire, etc.) associated with construction activities, and should consider the suitable response resources (medical, fire-fighting, etc) for all related foreseeable emergencies, which are necessary to mitigate the remote location of the work sites and consequent increased response times. It likely to be necessary to provide equipment and facilities within the construction camps.

582. With the management plans in place risk is assessed as low and the effects considered not significant, following the implementation of the proposed ongoing mitigation.

RISK RISK SEVERITY RISK RISK LEVEL SIGNIFICANT? LIKELIHOOD Inadequate safety controls and MAJOR POSSIBLE LOW NO risks to workers and the community

7.5.3 Utilities and Infrastructure

583. The site is remote with no utilities or infrastructure at the dam construction site. The contractor will make arrangement to access infrastructure to provide utility services at the Camp site (office accommodation). Permanent overnight accommodation is not anticipated for this project. International site staff will be accommodated in existing rental accommodation and local site staff will work from a home base. The contractor will make a commercial decision between connecting to utility services or work to a self-sufficient approach. Whichever option is adopted utility service provision must be operated in accordance with National standards and the requirements of the EIA in terms of noise, dust generation, water pollution, etc.

7.5.4 Site Construction Access Routes

584. Noise impacts along site access routes have been considered. It is anticipated that the impact can be considered as individual HGV units. Once the initial burst of activity has subsided truck access is anticipated to be less than one truck per hour during the working day, there will be no night-time access. There is a single access route to the site from the Cross Island Road. The access road passes between residential properties set back from the alignment by at least 10m. Actual monitoring of container truck movements on Port Access Road in October 2018 (see Table 5.16) suggests a sound power level at roadside of 82dB(A) from HGV passage and this will be attenuated to the IFC standard of 55dB(A) within 9m. Therefore, no significant impact from traffic movements is anticipated from traffic movements on the site access road.

7.5.5 Construction camps

585. Impacts. The contractor is expected to source semi and unskilled construction workers locally in the first instance. Expatriate management staff and skilled construction workers may be required but the numbers are likely to be low and it is anticipated that a construction camp requiring full time accommodation including canteen and ablution facilities will not be required. There will certainly be a need for office accommodation to fulfil management, site supervision, on site temporary works design and record keeping functions but solid and liquid waste disposal requirements will be very limited. It is unlikely that the office camp will be occupied overnight.

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586. Plant maintenance and manufacturing areas for crushing plant and concrete batch plant and storage areas will be required. Environmental impacts include noise from maintenance areas and any crushing plant, dusty works (from vehicle movements and operation of manufacturing equipment, rock crushers and concrete batching plant) and potential for adverse water impact due to runoff from unmade roads, oily runoff from manufacturing and storage areas and sewerage discharges from poorly maintained septic tanks / waste water treatment facilities.

587. The risk of adverse effects to due to the location, development, operation and decommissioning of construction camps will be managed though the contractor’s implementation of a Camp Management Plan and, followed by the development and implementation of a Health Plan, incorporated in the Health and Safety Plan.

588. Mitigation. Prior to start of site works, the contractor shall develop a Camp Management Plan. The Camp Management Plan will cross reference other sub-plans including; Water Resources Management Plan, Spill Management Plan, Air Quality Management Plan, Noise and Vibration Management Plan, Waste and Materials Management Plan, and others as required.

• All camp sewage will be managed in accordance with the measures in the Water Resources Management Plan.

• The contractor will be responsible for maintenance and clean-up of campsites and respecting the rights of local land users.

• Camp activities will be included in the Emergency Response Plan, and suitable response resources (medical, fire-fighting, etc) necessary to mitigate the remote location of the work sites and consequent increased response times. The construction camps will be staffed and equipped with a health clinic for all workers.

• The Camp Management Plan will incorporate and reference the requirements of the Local Employment and Procurement Plan and Gender Action Plan.

589. With these mitigation measures the risk is assessed as “low” and the effect is considered not significant, following the implementation of the ongoing mitigation and management.

RISK RISK SEVERITY RISK POST SIGNIFICANT? LIKELIHOOD MITIGATION RISK LEVEL Site specific impacts – MINOR POSSIBLE LOW NO construction camps

7.5.6 Construction Noise

590. Construction noise at the dam site: The main source of construction noise will be at the dam site and the areas immediately adjacent where the contractor will base material processing and manufacturing facilities. It is fortunate that there are no residential developments in the immediate area that will be impacted by this construction noise. The closest habitation is the staff house at the Alaoa Hydropower station that is approximately 300m downstream from the dam site and shielded from direct line of sight by topography. There are developments on the ridgeline to the east of the dam construction site but again these developments are over 300m distant and shielded by topography.

591. Noise from vehicles on access roads: In the assessment we must also consider the potential impacts from the vehicles travelling between the port, where construction plant and materials will be received in Samoa, and the construction site. There are existing residential properties adjacent to the access road.

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592. Construction traffic will only operate during the daytime hours, no night movements of vehicles are envisaged. The assessment is based on comparing the existing background noise levels on the existing road network (dedicated project noise impact survey Oct 2018) with the additional noise generated by the small numbers of construction vehicles that will access the site during the construction phase.

593. Impacts. Noise will be generated in the course of the dam at the dam site and its environs and to a lesser extent in the import and transportation of construction materials between port and site. In assessing construction phase noise impacts this EIA focuses on four areas of potential impact: (i) noise from ground- breaking – including quarry site operations; (ii) noise from dam construction compaction (rolling) and haul routes; (iii) noise from drilling and blasting (associated with quarrying); and (iv) noise from work site/yard, camp activities and transportation. The methodology for assessing the effects of construction noise from the Project can be divided into following general steps:

• Establish, through measurement, the current ambient noise environment for sensitive receptors that may in future be affected by construction noise from the Project • Identify those construction activities with the potential to generate significant construction noise levels • Analyse obtained equipment data and calculate noise emission at the source; • Assess the noise effects of the Project; • Develop best practicable noise mitigation measures.

594. While there are no residential developments close to the dam construction site, the contractor is required to minimise noise generation to preserve the current noise environment (reduce disturbance to fauna that move through the area during foraging, feeding and breeding). There are also areas of residential development along the site access road from the port. Some degradation of the existing noise environment is therefore expected and will require management by the contractor.

595. Assessment. Noise standards to be applied during construction are presented in Table. in These criteria draw from a review of Samoan and international standards. These levels should be applied at receptors in the vicinity of the Project.

Table7.14: Noise standards for construction

Noise Standard dB(A) Standard Receptor type Daytime Evening Night-time (0700-1800) (1800-2200) (2200-0700) Residential: Living quarters in apartments, rest houses, boarding houses, homes for elderly or disabled, sleeping quarters in kindergartens or residential schools Religious / Hospitals: Recreation areas on the territory Samoa* 75 60 - of hospitals and sanatoriums Schools: Classrooms, teachers' general office, school and conference rooms of other educational organizations, as well as public reading rooms Daytime (0700-2200) Night-time (2200-0700) IFC** Residential, institutional, educational: 55 45 Industrial, commercial: 70 70 * - Samoa standards – PUMA 2004. Noise Policy document, October 2011 ** - IFC Standards27 EHSG: Environmental – Noise Management (April 30, 2007

27https://www.ifc.org/wps/wcm/connect/4a4db1c5-ee97-43ba-99dd-8b120b22ea32/1- 7%2BNoise.pdf?MOD=AJPERES&CVID=ls4XYBw

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596. Normal working hours are from Monday to Saturday from 8 am to 6 pm. Night-time working and working on Sunday or public holidays is not foreseen

597. There is no site specific information available on construction methods, plant and equipment before the Works Contract is awarded, but based on the anticipated scope of works it can be assumed that standard construction methods and equipment would be used for the civil works for the operation of borrow areas(quarry site) the dam construction and access along the project access road.

598. The construction equipment expected to be employed for construction has been identified and Table 7.15 below lists the likely construction equipment usage at the major work sites. Stationary plants and equipment are not considered, as the location of the stationary plants should be selected to be sufficiently distanced from sensitive receptors.

Table 7.15: Equipment likely to be used during major construction activities

Activity Equipment Work Site Location Quarry sites / Borrow areas Hydraulic hammers Immediately behind the dam site Wheeled Loader (within the future inundated area) Trucks Excavators Breaker Site Clearance Scraper Across the work site Earthworks Scraper At the dam site Excavators Loaders Dump trucks Graders Dozers Vibrating rollers Compactors Construction of the RCC dam Excavators At all dam site structure Drilling Rig Concrete Mixer Trucks Concrete pumps Trucks Crane Poker Vibrator Diesel Generator On Access Roads HGV Container truck / similar Between port and works site Water Tanker Road Sweeper Manufacturing Area Batching Plant At the manufacturing area (behind Conveyor Belts dam site in inundation area) Excavator / Loader Concrete lorry Mixer Lorry Construction camp Nil – envisaged to be only office At the construction camp offices type activity, occasional access by adjacent to the dam site road vehicles

599. Ideally, noise data in calculations should be for the specific equipment to be used on site. However, at the assessment stage the equipment has not been selected, and data are not available. Therefore, for initial predictions reference noise data from BS 5228-1:2009 has been used.

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600. BS 5228-1:2009 includes reference noise level data for typical construction equipment. These data have been obtained from measurements at construction sites in the United Kingdom on similar types of equipment to that used internationally. These data are used as a guide to establish the construction noise emissions.

601. Where there is a moving source, the BS 5228-1 data relates to the equipment at the nearest (loudest) point rather than being an average value. For slow-moving sources in a constrained area, BS 5228-1 makes allowance for the times when the equipment is further away from the houses and therefore quieter. This is done by effectively reducing the operating time, using the correction factor extracted from equation F9 within BS 5228-1:

Equation 2: Equation to determine sound power level from multiple sources

where:

LAeq(t) is the is the combined equivalent continuous A-weighted sound pressure level, in decibels (dB), over a given period T;

Li is the individual equivalent continuous A-weighted sound pressure level, LAeq, for an item of plant or activity during a period ti , in decibels (dB);

n is the total number of individual equivalent continuous A-weighted sound pressure levels to be combined.

602. In quantifying potential construction noise impact assessment, the Technical Memorandum on Construction Noise of the Environmental Protection Department, Hong Kong Government has been followed28. This is a stepped process:

• Step 1 – Identify construction plant for major construction activities (see Table 7.15) • Step 2 – Aggregate the sound power levels of the construction plant (see Appendix 4 – Construction Noise Calculations) • Step 3 Determine the distance required to attenuate construction noise to an acceptable level (see Table) • Step 4 Confirm that noise can be attenuated at sensitive receivers. If it cannot look at mitigation options e.g. quieter plant, noise barriers.

603. In the following table the construction activity, construction plant, distance attenuation requirements and residual impact are presented. The full calculations are presented in Appendix 5 – Construction Noise Calculation.

28 The information on source noise and distance attenuation has been extracted from the Hong Kong Environmental Protection Department publication “Technical Memorandum on Noise from Construction other than Percussive piling. Table 2 Sound Power Levels for items of Powered Mechanical Equipment (PME) and Table 4 Correction factors to obtain Predicted Noise Level.

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Table 7.16: Construction noise impact summary by activity

Activity Equipment Predicted Sound Distance Notes Power level at attenuation to source [dB(A)] achieve IFC standard of 55dB(A) (m) Rock Drill (Crawler Mounted) 128 + 128 + 122 + 1) Quarry sites / Wheeled Loader 112 + 112 equates Closest NSR < >700m Borrow areas Trucks to a point source of 700m Excavators 132dB(A) Breaker Scraper Closest NSR < ‘2) Site Clearance 119 dB(A) 318 to 351m 400m Scraper Excavators Loaders 117 + 115 + 113 Dump trucks Closest NSR < ‘3) Earthworks equates to 352 to 387m 400m Graders 120dB(A) Dozers Vibrating rollers Compactors Excavators Drilling Rig Concrete Mixer Trucks 113 + 1113+ 113+ ‘4) Construction of 112+ 109+ 109+ Closest NSR < Concrete pumps 352 to 387m RCC dam structure 108 equates to 400m Trucks 120db(A) Crane Poker Vibrator Diesel Generator HGV Container truck / Actual ‘5) On Access similar measurement No residential 9m Roads 82dB(A) (Table closer than 9m 5.16) Batching Plant Conveyor Belts 112 + 112 +108 + ‘6) Manufacturing 108 + 108 + 100 + Closest NSR < Excavator / Loader 261 to 268m Area 100 + 90. equates 400m Concrete lorry Mixer to 117dB(A) Lorry Construction camp Nil – envisaged to be only office type activity, occasional n/a n/a n/a access by road vehicles

604. Mitigation. During noisy activities the contractor shall minimise noise impact by use of natural topographic barriers or by placing physical barriers between noise generating activities and sensitive uses and only work during daytime hours, unless dispensation is arranged. To minimise noise impacts on nearby residents all vehicles will be equipped with exhaust mufflers and regularly inspected to ensure they are operating efficiently. In addition, works sites will only operate during daytime hours.

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605. Blasting, or other high noise activities (such as asphalt plants, cement plant, and stone crushers) should not be carried out in the early morning or evening when background noise levels are low. All residents that will be affected should be informed of the date and time of blast well in advance. Blasting should preferably be carried out at the same time each day.

606. Noise impacts along site access routes have been considered. It is anticipated that the impact can be considered as individual HGV units. Once the initial burst of activity has subsided truck access is anticipated to be less than one truck per hour during the working day, there will be no night-time access. There is a single access route to the site from the Cross Island Road. The access road passes between residential properties set back from the alignment by at least 10m. Actual monitoring of container truck movements on Port Access Road in October 2018 (see Table 5.16) suggests a sound power level at roadside of 82dB(A) from HGV passage and this will be attenuated to the IFC standard of 55dB(A) within 9m. Therefore, no significant impact from traffic movements is anticipated from traffic movements on the site access road.

607. The requirements for noise mitigation are identified in the EMP section of this EIA. The precise mechanisms will be identified in the CEMP, but contractors will be required to develop and implement the following management plans, which will be approved and monitored during construction by the PMU and Supervising Engineer:

• Noise and Vibration Management Plan (NVMP) • Traffic Management Plan (TMP) • Blasting Management Plan

608. Additionally, location specific noise mitigation measures will be covered by the required plans for these operations, including: (i) Camp Management Plan; (ii) Concrete and Asphalt Production Management Plans; (iii) Construction plans and Method Statements; and (iv) Method Statements for Temporary Activities.

609. With mitigation in place the post mitigation risk is assessed as “low” and the residual effect is not considered significant.

RISK RISK RISK POST SIGNIFICANT? SEVERITY LIKELIHOOD MITIGATION RISK LEVEL Construction noise MINOR IMPROBABLE LOW NO – due to remoteness of site

7.5.7 Vibration

610. Impacts. The Alaoa dam construction site is remote from residential development (> 800m) and though construction activities including quarry development, materials processing, compaction activities and the movement have potential to create vibration impact there are no sensitive receivers likely to be affected. However, there is potential for vibration impact on the access route to the construction site from the Cross Island Road, where residential properties are located close to the existing roadway.

611. Samoa has no national standards for vibration.

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612. Vibration caused by construction can cause disturbance to residents close to the works and damage to property. The effects of vibration on structures depends on the construction machinery and equipment used (emission source) and on the structural conditions of the potentially affected building structures (receptors).

613. The buildings within the Project area are relatively modern structures, generally formed in locally sourced materials (wood, mud brick and concrete blockwork). Buildings are generally setback from the road edge within a defined compound further defined by a chain-link fence. Buildings were casually observed to be in good condition and did not appear to be suffering from surface cracking due to ground settlement / poor foundations.

Plate 7.2: Proximity to access road - Alaoa Primary School; Alaoa Road at Cross Island Rd junction

614. As there are no standards for vibration in Samoa threshold criteria recommended by USA CALTRANS (2013)29 were used for the assessment of vibration on building structures. These criteria draw from a large review of international standards including, the American Association of State Highway and Transportation Officials (AASHTO), Swiss Association of Standardization, and British Standards. The cited threshold criteria are shown in Table 7.17.

29 California Department of Transportation. 2013. Transportation and Construction Vibration. Guidance Manual.

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Table 7.17: Guideline vibration damage potential threshold criteria

Maximum PPV (in/sec) Structure and Condition Transient sources Continuous/frequent Extremely fragile historic buildings, ruins, ancient 0.12 0.08 monuments Fragile buildings 0.2 0.1 Historic and some old buildings 0.5 0.25 Older residential structures 0.5 0.3 New residential structures 1 0.5 Modern industrial/commercial buildings 2.0 0.5

Note: Transient sources create a single isolated vibration event, such as blasting or drop balls. Continuous/frequent intermittent sources include impact pile drivers, pogo-stick compactors, crack-and-seat equipment, vibratory pile drivers, and vibratory compaction equipment. Source: California Department of Transportation (2013)

615. Existing buildings along the project road are predominantly buildings with plastered walls, wooden ceilings and walls in blockwork. A conservative approach was adopted with older buildings taken as a reference for the assessment (worst case). This categorisation was based on the field observations, not a full structural survey. There are no facilities with equipment sensitive to vibration in the immediate vicinity of the alignment.

616. For historic and old buildings, the given threshold (acceptable) value is 0.25 in/sec for continuous or frequent intermittent sources typical of construction vibration.

617. For the various type of construction machinery the average vibration levels at a distance of 25 feet (approximate 7.5 m) from the emission source are indicated in Table 7.18 (Caltrans 2013).30

Table 7.18: Vibration source amplitudes for construction equipment

Reference PPV at 25 ft./ Equipment Reference in dB approximate 7.5 m (in/sec) Vibratory roller 0.210 106 Large bulldozer 0.089 98 Caisson drilling 0.089 98 0.089 98 Loaded trucks 0.076 97 0.076 97 Jackhammer 0.035 90 0.035 90 Small bulldozer 0.003 69 0.003 69

Source: California Department of Transportation (2013)

30 California Department of Transportation. 2013. Transportation and Construction: Vibration

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618. Using these source levels, vibration from the equipment can be estimated by the following formula:

n • PPVEquipment = PPVRef * (25/D) in/sec

• Where: PPVRef = reference PPV at 25 ft.

• D = distance from the equipment to the receptor in feet.

• N = 1.1 (the value related to the attenuation rate through ground)31

619. By transposing this formula, the required minimum distance can be calculated as follows: 25 퐷 = 푝푝푣 푒푞푢푖푝푚푒푛푡 푛√ 푝푝푣 푟푒푓

620. By applying this formula and using as threshold values for PPVEquipment and PPVRef 0.25 in/sec the calculated minimum safe distance for the fragile buildings adjacent to the project road is 25 feet (7.5 meters). The threshold value used for the building structures is valid for historic and old buildings and emission from a continuous source32. The reference PPV applied for the construction machinery (0,25 in/sec) is slightly above the standard PPVRef of the vibratory roller in Table 7.18. Hence the assessment can be considered to be conservative.

621. It is therefore be concluded that fragile buildings closer than 7.5 m to the road edge are at risk of damage. During site walkover no buildings were observed to be within 7.5m of the road edge.

622. Mitigation. While it is not anticipated that vibration will be an issue on the project a precautionary approach is proposed. The contractor shall undertake a precondition survey along the alignment of the access road to the site to identify vibration sensitive sites and vulnerable buildings and identify any precautions to be adopted. These may include reduced speeds to be adopted on the access rout, or as a last resort, at receptor mitigation e.g. insulation at affected SR / dwellings.

623. The preconstruction survey should be jointly conducted by the contractor and the Engineer to document the pre-construction condition of the structures, including all defects and existing damage. Pre- construction surveys should have the following characteristics:

• The surveys should be conducted in the presence of and with the permission of the property owners. The survey reports should also be verified by the property owners. Secondary purposes of the pre-construction surveys include answering any questions the building owner may have regarding the project and looking for anything that might require correcting before construction starts. Most building owners will not have experience with construction vibration and may have concerns about their own safety and the safety of their structures. • Knowledgeable persons should attend to adequately answer questions. If the situation warrants, ad-hoc meetings should be held and a presentation made that explains the reason for the project, that construction will be necessary, what the residents can expect to hear and feel from the construction, any specific warning signals that will be used, and the intent of the pre-construction surveys.

31 The value 1.1 for n is suggested in CALTRANS (2013). It is used for class III soils which are defined as Hard Soils, such as: dense compacted sand, dry consolidated clay, consolidated glacial till, some exposed rock (cannot dig with a shovel, need a pick to break up). 32 Threshold criteria according to Table 7.18 (Table 19 in CALTRANS (2013).

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• For purpose of assessment the magnitude of impact both elements, the type of receptor (structural condition of the potentially affected building) and the type of machinery (emission source) need to be considered. • Based on the survey results, the contractor shall identify vibration sensitive sites and vulnerable buildings and identify the precautions to be adopted. These may include reduced pace of construction activity, low vibration plant and machinery and, as a last resort, at receptor mitigation e.g. insulation at affected SR / dwellings

624. For vibration it is considered that only the site access road needs to be considered as the construction site is remote from any development. However, this does not remove contractor responsibility to carry out works with the minimum levels of disturbance on the existing environment. With the identified mitigation in place vibration impact is considered to be low.

RISK RISK POST SIGNIFICANT? RISK SEVERITY LIKELIHOOD MITIGATION RISK LEVEL Construction vibration from activities at IMPROBABLE LOW NO dam construction site (due to Moderate remoteness of site) Vibration on construction site access Moderate IMPROBABLE LOW NO road (damage to (due to low buildings / levels of annoyance) activity)

7.5.8 -Cultural and physical resources

625. Impacts. No archaeological or cultural resources are expected to be encountered during project implementation. A dedicated archaeology study Volume 2 - Annex F) did not identify any area of Archaeological concern), no findings have been reported and the majority of the works are in areas where traditional agricultural works have disturbed surface layers. Any resources that may have been present are likely to have been damaged by the previous works, and / or be in a poor state of preservation.

626. Neither the consultations nor archaeological survey assessment identified cultural heritage sites as being affected by the proposed dam construction works.

627. However, a chance find procedure is included in the construction EMP and will be implemented during construction. In the case of discovery of buried archaeology during construction activities, the works shall be immediately stopped, and the relevant authority is to be informed. Works will proceed following discussion and guidance obtained from the Center for Samoan Studies, National University of Samoa.

628. The need for the contractor to include chance find procedure is included in the ESMP for this ESIA and the contractor will include their procedure in the Cultural Heritage Management Plan.

629. The post mitigation risk is assessed as low and the effect is not considered significant

RISK RISK SEVERITY RISK POST SIGNIFICANT? LIKELIHOOD MITIGATION RISK LEVEL Impacts on historic cultural and INSIGNIFICANT IMPROBABLE LOW NO archaeological monuments

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7.6 Operation Impacts

7.6.1 Operation impacts on the physical environment

630. Air quality. The project is not anticipated to generate any air quality impacts during its operation phase.

631. Hydrology and water quality. The project is not anticipated to generate any Water quality impacts during its operation phase.

632. Waste management. Given the low activity levels and the nature of operation of the multi-purpose dam it is not anticipated that there will be any operational issues relating to waste management during the operation phase.

633. Geomorphology and sedimentation impacts. The main potential impacts of the proposed dam and its operation on geomorphic processes and forms are:

• Trapping of sediment in the dam reservoir, reducing the load of sediment to the river downstream, and to Apia Bay; • Scour of the shoreline of the reservoir rim due to focus of wind-generated waves at the normal full supply level (NFSL); • Potential mortality of trees, shrubs and ground cover on hillslopes within the reservoir flood storage area during extended periods of inundation during high inflows, with subsequent risk of hillslope instability; • The rate of reservoir water level drawdown on flood recessions exceeding the rate at which hillslope soils can drain, with subsequent risk of hillslope slumping; and • Altered hydrology reducing the frequency of bed material mobilization and reducing bed material load.

634. The likelihood and consequence (risk) of each of the identified direct impacts of the proposed Alaoa dam were assessed. The impacts were judged almost certain to occur, but the consequences were subjective and partly of an ecological nature.

635. Reduced suspended sediment delivery to the river system downstream of the dam cannot be mitigated, but the geomorphic consequence of this is insignificant because nearly all of the sediment that would otherwise have passed through the river system would have entered Apia Bay and then flowed out to deeper water.

636. Deposition of a large volume of fine sediment within the reservoir can only be mitigated by occasional flushing of the sediment by opening the low-level offtake. This procedure was estimated to be required every 15 – 20 years, but the estimate is uncertain. The consequences of sediment flushing can be mitigated by arranging it to be done at a time when the catchment is experiencing a natural flood event, to assist transport of the turbid water to Apia Bay.

637. Downstream of the dam, the rate of bedload transport will be reduced due to reduced magnitude of flood peaks. However, it appears that the natural rate of bedload transport is low, so the consequences of a reduction are likely to be minor.

638. With the dam operational, channel forming flows will operate at a lower magnitude, so the river will likely slowly adjust by contracting in width. The potential for mitigating this impact by environmental flows was investigated by Elvey and Gippel (2019). Their conclusion was that the most appropriate course of action was to allow the channel to contract and stabilise at a new dynamic equilibrium.

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639. Application of the RUSLE by Entura (2018) over 32 sub-catchments within the catchment of the proposed Alaoa dam give an estimate of mean annual total soil loss of 61,100 t/yr (3,715 t/km2/yr). Assuming a sediment delivery ratio of 1, the mean annual sediment load of the catchment would be the same. This estimate is lower than those of the Fournier and BQART equations, but still much higher than the estimates made the empirical relationships of Holst Rice et al. (2016).

640. The Fournier (1960) equation was applied to the entire catchment of the proposed Alaoa dam assuming rainfall data from Afiamalu applied to the Eastern branch, Middle-eastern branch, Middle branch and Western branch, rainfall data from Alaoa applied to the Far western branch and area downstream of proposed Alaoa dam, and rainfall data from Apia applied to the Lower catchment.

641. Scour of the shoreline of the reservoir rim due to the action of wind waves is inevitable. Mitigation of this would be impractical, so it is recommended to allow the shoreline to erode to bare rock.

642. Submergence and waterlogging of trees, shrubs and ground cover on hillslopes within the reservoir flood storage area, as well as rapid drawdown, will create the risk of loss of soil and vegetation. It is recommended to seek additional expert advice on this matter. Mitigation could take the form of management of water levels and maintenance of good cover of vegetation that will tolerate the hydrologic and hydraulic conditions within the flood storage area.

643. A review of the current understanding of the geomorphology of Apia Bay suggested that a change in the Vaisigano River flow and sediment budget due to operation of Alaoa dam would appear to have a minor impact on sediment-related processes in the bay. This is explained by the open nature of the estuary (despite harbour reclamation), with geomorphic processes dominated by marine energy and inputs. The vast majority of the sediment originating from the Vaisigano River is rapidly transported offshore to deeper waters. The relatively small quantity of fluvial sediment that normally deposits within the confines of the Bay will continue to be supplied by the Vaisigano River. On this basis, no environmental flow recommendations were made for the estuarine environment of Apia Bay.

644. The mid-level outlet for the dam will operate occasionally to reduce the storage level and will discharge from the dam wall, adjacent to the power station, to the river channel below.

645. Monitoring of geomorphic form and process should focus on indicators that effectively characterise the main project impacts identified in this report, to determine if and to what extent the predicted impacts occur, and also the implemented mitigation measures, to determine the effectiveness or otherwise of the measures. The monitoring program would be a component of an adaptive approach to management of the dam and the Vaisigano River system.

646. Monitoring that will assist sediment and erosion management includes:

• Annual sounding survey of the reservoir to determine sediment deposition rate; and • Surveillance of the reservoir flood storage area immediately following drawdown of raised water levels in the wet season. Initial survey could be done by AUV (aerial unmanned vehicle), with any areas of potential vegetation death or soil instability inspected on the ground.

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7.6.2 Operation impacts on biological environment

647. Environmental flows. The main purpose of the proposed dam is flood protection. The dam wall is 60m-high but the storage level will typically be 26 metres below the spillway level to retain the capacity to store large inflows and prevent flooding downstream. A 60m high dam wall will be an impassable barrier to the upstream migration of species into the reaches above the dam. Mitigation measures to assist species to move upstream of the dam are not considered feasible because the design purpose of the dam to prevent spill will provide no certain means for the aquatic larvae or adult eels to migrate back downstream to the sea. Therefore, the migratory species present will no longer occur in the east or middle-east branches of the river, and while migration into the east branch is already significantly compromised by existing flow regulation, the implementation of the recommended environmental flows will mitigate impacts, and even enhance aquatic habitat, downstream from the Samasoni weir and the final reach of the middle branch (before it joins the west branch).

648. The objectives of the environmental flow mitigation is to restore flow lost to the current hydro-power schemes and to offset the impacts of the new project by improving migration opportunities into the lower (main branch), mid (main, middle and west branches) and upper reaches (middle and west branches) of the catchment. If the environmental flow is implemented, operation of the new dam is predicted to result in no net loss of biodiversity in the catchment.

649. It is proposed to release a permanent baseflow from Samasoni weir and from the offtake weir on the middle branch. A monthly fresh rule is also proposed from these locations to increase the frequency and duration that higher flows are delivered downstream.

650. The release of a permanent baseflow from these reaches will provide the following environmental benefits:

• Restore permanent aquatic habitat to 4.2km of the main channel downstream from the Samasoni weir and the final 1.3km reach of the middle branch before it joins the west branch; • Allow populations of goby, eel, shrimp, prawn and macroinvertebrate to establish in these reaches; • Restore connectivity and migratory pathways from the sea to the upper reaches of the catchment. Specifically, a permanent baseflow will increase opportunities for: o the downstream migration of larval gobies, prawns and shrimps to reach the sea o adult eels to migrate downstream to the sea to breed o upstream migration of juvenile gobies, eels, prawns and shrimps from the lower reaches and the sea; and • Provide social benefits for increased access to permanent flowing reaches for washing and recreational fishing,

651. Periods of elevated flows perform important ecological functions in rivers. As for baseflows, the existing hydro-power schemes significantly reduce the magnitude, duration and frequency of elevated flows. A monthly fresh rule is proposed to increase the frequency that elevated flows are passed downstream from Samasoni Weir and from the middle branch weir and is predicted to improve aquatic habitat by providing:

• Attractant cues to initiate migration upstream from the river mouth to the bay to and upstream from the lower reaches to the middle and upper reaches • More rapid downstream transport of newly hatched larvae of fish, prawn and shrimp species from the river to sea. Larvae must reach the sea within days to avoid starvation

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• Important life history cues for resident freshwater species such as aquatic macroinvertebrates; and • Important fluvial geomorphological functions of scouring fine sediment from the surface of the bed and disturbing filamentous algae.

652. The project will also alter the flow regime downstream, particularly the high flow regime. Flow provides important habitat maintenance functions (turnover of sediments and nutrient supply) and provides physical habitat. Flow also provides life history cues for freshwater aquatic species, including species which may use high flow events as triggers for moving upstream into the river from the marine environment, and for transferring larvae downstream into the marine environment.

653. Capacity building will be needed within government to develop the skill sets to implement, operate and monitor the proposed environmental flow. This will be provided though the development of environmental flow policy and guidelines and training to be provided to MNRE and EPC as part of the BOP.

654. Fish ladder and structure. The structure to be designed and installed for upstream of Samasoni weir and downstream of the confluence of the western branch, to encourage fishes up the western (and to be restored branch – which will provide better quality habitat and the fish can go farther upstream) rather than up the middle branch (to the toe of the dam) will assist the mitigation of aquatic habitat impacts during the operation phase to be provided the environmental flow.

655. Invasive species control. Within the site, during the operations phase, EPC will need to maintain the invasive species control measures implemented as part of the BOP to ensure that invasive species are not introduced to the site and/or spread beyond the site. This will need to be managed in coordination with MNRE.

7.6.3 Operation impacts on socio-economic environment

656. Worker health and safety. Standard health and safety provisions currently enacted by EPC will be followed and no worker health and safety issues are anticipated.

657. Noise. No operational noise impact is anticipated from the project. Daily vehicles accessing the site will be limited to normal road vehicles (4WD) required for maintenance purposes. The hydropower plant is remote from any noise sensitive development and the turbines will be enclosed within a structure that will contain any noise generated. Site observations at existing hydropower stations had no significant noise impact on the surrounding area.

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8 Environmental Management Plan

8.1 Introduction

658. The objectives of the EMP, including the monitoring plans, are:

• To ensure project components are conducted in compliance with the national laws and regulations as well as the requirements of the ADB; • To measure the success of proposed mitigation measures in minimising and/or reducing potential environmental, health, safety and social impacts; • To continuously control the changes to baseline environmental, health, safety and social conditions during pre-construction, construction and operation activities; • To facilitate a continual review of activities based on performance data and consultation feedback; and • To implement corrective actions or new adaptive management programs, as required

8.2 Institutional Responsibilities

659. The following roles and responsibilities have been established for implementation and management of this EMP.

8.2.1 Project Management Unit of Electric Power Corporation

660. The EPC PMU, as implementing agency will be responsible for ensuring compliance with and implementation of all national and international environmental, health, safety and social policies, guidelines and performance requirements of both Samoa and ADB and any others who are subsequently involved in the Project.

661. The PMU will be responsible for the overall implementation of the mitigation measures and requirements specified within the EIA disclosure package for the Project. They will be required to oversee implementation of the EMP developed by the contractor to ensure it fulfils all identified environmental, health, safety and social requirements under the grant agreement for the Project. The PMU are responsible for ensuring roles and responsibilities are clearly identified and allocated for environmental, health, safety and social, gender, both within the PMU itself, within the contractors’ arrangements and for the handover to operations.

662. The PMU will be responsible for the implementation and conformance of the GRM to ensure that all grievances and/or objections (if any raised by the local community and/or workers) are received, acknowledged and addressed as per the grievance procedure presented in the stakeholder engagement plan (SEP).

663. Within the PMU there is an environment officer and social safeguards officer who have been employed for some years and have been building up project experience and developing safeguards capacity. The PMU will be supported by a CSC which will include an international environmental specialist and national environmental specialist to work with the existing safeguards staff of the PMU.

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8.2.2 Construction supervision consultant and supervising engineer

664. Monitoring of environmental quality and of the implementation of mitigation measures will be performed by the CSC with sufficient TORs and staff-time for this task. Therefore, as a minimum, it is required for CSC to recruit 3 months of a Senior International Environmental Specialist and full time for a National Environmental specialist over 3 years during the project implementation. In addition, a Senior International Occupational Health and Safety Specialist will be employed for 4 months during the project duration and a National Occupational Health and Safety Specialist half time (18 months) during the implementation of the project under the CSC contract.

665. The Supervising Engineer will be responsible for supervising the contractor to ensure that recommendations and requirements, as set out in this EMP and other documentation are applied. They will be responsible for continuous monitoring of the processes and activities undertaken by the contractor, and specifying measures to be implemented by the contractor, to address any areas of non-compliance

8.2.3 Lender’s Technical Advisor

666. The ADB will appoint a Technical Advisor who will be responsible for reviewing documentation on behalf of the ADB and who will assist the CSC in monitoring the contractor’s implementation of the activities specified in the EMP on a quarterly basis; this will be equivalent to an audit role. They will be responsible for providing a monitoring report to the Lenders that evaluates compliance with both the EMP and ADB requirements and providing recommendations to the Supervising Engineer and contractor to address any areas of non-compliance.

8.2.4 Design and build contractor

667. The design and build (DB) contractor will be responsible for establishing an environmental management system (EMS) covering the design, pre-construction, construction and handover stages of the Project in line with ADB and CSS requirements and good practice. The EMS will be outlined in the CEMP to be developed and approved prior to commencement of any activities on site. (see also Section 8.3.1)

668. The contractor is also responsible for implementing any environmental, health, safety and social measures identified in the CEAR and development consent (with or without conditions), that the PMU has developed for submission to the PUMA.

669. The contractor will be responsible for submission of relevant reports to the Supervising Engineer, for subsequent approval by the Supervising Engineer, PMU and/or the MNRE, as appropriate.

670. The contractor must ensure the EMP and approved CEMP is implemented by competent individuals, using approved methods of monitoring, and calibrated equipment (field testers and hand-held equipment) where appropriate. Calibration must be done regularly. All calibration records and monitoring results, along with the copies of the site records, certificates, permits and documents shall be submitted and kept by the PMU.

671. The contractor shall appoint a dedicated EMO and HSO (and deputies) responsible for undertaking health, safety and environmental management tasks as set out in the contract and lead the monitoring team. These personnel will be supported by additional personnel with specific EHS responsibilities. The Environmental and Safety team will report directly to the contractor’s Project Manager.

672. The responsibilities of the EMO and HSO will include:

• Ensuring the contractor implements the environmental protection and management specifications set out in the contract and the approved CEMP;

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• Undertaking day-to-day environmental and safety management tasks as required for the Project and weekly environmental and health and safety audits; • Maintaining a daily Site Diary recording all relevant matters concerning environmental and safety management on the Site including protections and controls, audits, inspections, and related incidents. Making the Site Diary available for inspection by the Engineer upon request; • Participating in joint inspections to be undertaken by PMU, ADB and other environmental organisations and the CSC environmental team; and • Preparing and submitting the reports as required by the contract and the CEMP.

673. The contractor shall also appoint a dedicated person with responsibilities for managing the requirements of the contract and EMP related to social and gender matters. On-site support from an experienced consultant specialising in health and safety, providing additional support and advice, and building the capacity of the contractor will be engaged. The consultants will assist the contractors in developing, implementing and monitoring the Health and Safety Plan. Other safety, environmental and/or social specialists may be engaged to provide support as necessary.

674. An organisation plan for the construction phase of the works is presented below.

Figure 8.1: Organisation plan for contractor construction staffing

International Financing Agency Implementing Agency: Electric Power Corporation, Samoa Asian Development Bank Existing Project Management Unit: Manager Environmental safeguards Social Safeguards Executing Agency Ministry of Finance Alaoa Project Management Unit: Design / Construction Supervision Team: National Environmental safeguards Engineer National Social Safeguards National Environmental safeguards International Environmental (part time) National Social Safeguards International Environmental (part time)

Engineer has "Delegated Powers" under Contract

Construction Contractor Contractor - Site Project Manager

Environmental and Social Team Environmental and Social Team (As required) Construction Team (Full Time)

(Full Time - provisional) CEMP Author Engineers Contractor and EPC Between Contract Construction Environmental Manager Arborist (for pre construction habitat) Foremen Environmental Clerk of Works Avifauna (Mao pre construction nest survey) Plant operators Environmental Assistant Skilled Workers Health and Safety Semi Skilled Workers Unskilled Workers

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8.3 Framework of Environmental Plans

8.3.1 Environmental management system

675. The contractor will be responsible for implementing an EMS that is in line with international standards. The contractor will be required to appoint appropriately qualified specialists with the following expertise, to ensure is the EMS is implemented to the required standards:

• Environmental; • Health and safety; and • Social (including gender and stakeholder engagement).

The EMS will include a risk register, GRM register and accidents/incidents register which the contractor will be responsible for updating on a weekly basis throughout the pre-construction and construction period, and more frequently when required.

676. The contractor must conduct an initial environmental, safety and social induction course for construction workers regarding health and safety measures, emergency response in case of accidents, fire, earthquakes, flash flooding, environmental and community interactions, grievance procedures etc. They must also develop and implement an environmental, health and safety and security training program, and conduct meetings on a monthly basis with the PMU.

8.3.2 Framework of the plans

677. In preparing the CEMP and other management plans, the contractor will develop, and submit for review and approval prior to commencement of works, a number of detailed management plans. The timeframe and process for preparation, review and approval will be agreed by PMU, contractor and ADB early in the design and pre-construction phase. The general outline of the plans is provided below. Each plan should contain at least the following:

• Purpose • Definitions • Links, as required, with other plans (i.e. grievance redress mechanism (GRM), stakeholder engagement and communication plan, CEMP, health & safety etc) • Organizational structure and arrangements for implementation of the plan • Risk assessment (or other) methodology to identify aspects/impacts/risks to focus on for mitigation and management • Performance indicators or standards to be followed/met plus any additional targets cited in EMP in EIA • Mitigation and management measures • Site-specific plans for each of the components (maps, drawings, overlays etc), • Costs and budget • Monitoring and reporting requirements (to link with monitoring plans). • Checklists and forms (for recording compliance, registry, monitoring, corrective actions etc).

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678. Dam safety plans. Dam safety plans will be prepared in accordance with international standards and will include:

• Construction and Quality Assurance Plan • Operation and Maintenance Plan • Instrumentation Plan • Emergency Preparedness Plan

679. All plans relating to dam safety and response to operations related emergency events will be prepared by the DB contractor and reviewed by the PMU, ADB, LTA and additional advisors engaged for the specific purpose.

680. Construction EMP. The CEMP may also comprise a number of sub-plans as per Figure 7.5 and will include site-specific plans for the infrastructure components - access roads, power station, penstock etc - comprising several site-specific plans. Each site-specific plan should be prepared following steps including:

• Define boundaries • Identify sensitive receptors and environmental values • Specify construction activities (according to program and schedule) • Conduct risk assessment • Assign environmental mitigation and management measures • Prepare site plans and construction methodologies • Prepare environmental work plans (for when different work activities are required at different times or at different locations. Environmental work plans are similar to work method statements.

681. The CEMP also needs to identify how the developer will implement the relevant aspects and processes of the GRM and SEP.

682. As a guide to preparation of CESMP an outline of environmental specifications for construction is provided in Table 8.2.

683. Stakeholder engagement plan. The SEP describes the purpose, method and outputs of the project being implemented by the EPC, including the biodiversity protection and enhancement measures developed in the BMMP and BOP, and the stages and processes for communication. The SEP covers the requirements of relevant country laws, current practice in respect of communications and consultations and also complies with ADB requirements.

684. The purpose of the SEP is to guide what types of information need to be provided to and obtained from stakeholders, when and how such information is communicated, and how the information is to feed into the different project stages and aspects including feasibility study, detailed design, construction, and operations. It provides an overall mechanism for guiding communications about the project for the EPC, other relevant government agency staff, implementation and supervisory consultants, and the primary beneficiaries and other stakeholders (such as civil society organizations). Importantly, the SEP is based on local custom and tradition to ensure it facilitates meaningful consultation.

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685. The SEP is integrally linked with the project’s GRM that will also be reflected in the CEMP and other plans as required. The GRM sets out the process for resolving concerns or complaints and shows how communities and other stakeholders can lodge any complaints or concerns about the project at different stages/levels.

686. The SEP will cover:

• Project communications o Meaningful consultation principles o Overall communication approach o Stakeholders and target audiences o Key communication outcomes o Medium of communications with external stakeholders o Key messages • Project stages and communication outcomes o Preparation o Construction o Operations o Decommissioning o Monitoring • Project’s GRM and disclosure requirements.

687. Labor and working conditions management plan. Construction projects, especially those comprising large civil works, require labor force and associated goods and services that cannot always be fully supplied locally. In such cases, the labor force (total or partial) needs to be brought in from outside the project area. In many cases, this influx is compounded by an influx of other people (“followers”) who follow the incoming workforce with the aim of selling them goods and services, or in pursuit of job or business opportunities.

688. The purpose of the labor and working conditions management plan influx management plan (LWCMP) is to set out the objectives in relation to management of project-induced in-migration and its impacts and to successfully implement measures to manage the in-migration, and avoid, prevent, and mitigate the direct and indirect adverse impacts associated with project-induced in-migration. All stakeholders have a role to play in managing in-migration.

689. The LWCMP will need to:

• Identify project components/requirement for labor and potential for in-migration • Scale of in-migration and its impacts • Management of project-induced in-migration into the project area, which includes minimizing in-migration, managing the inflow of in-migrants, and managing the physical and social footprint of in-migration within the project area • Mitigation of adverse impacts associated with in-migration • Buy-in and capacity of potential partners to collaborate in the design and implementation of the measures to manage the in-migration

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• Resource costs of selected management approaches • Stakeholder engagement and monitoring and information flows.

690. The LWCMP needs to be clearly linked with the SEP.

691. Health and safety plan. The purpose of the health and safety plan (HSP) is to establish and maintain an effective health and safety management system. The HSP will demonstrate the developer is committed to implementing a structured approach to workplace health and safety in order to achieve a consistently high standard of safety performance. The HSP applies to all officers and workers and to other persons at risk from work carried out at workplaces.

692. The HSP will assist in meeting its obligations in accordance with work health and safety legislation of Samoa and comply with the requirements of the World Bank Group’s EHSG.

693. The HSP will cover:

• Health and safety arrangements o Responsibilities o Communication arrangements (incl. important contact numbers) o Hazards and risk assessment (activities such as working at height, working in confined spaces to be identified) o Risk register and incident reporting • Inspections, training and reporting o Emergency procedures (link to emergency response and evacuation plan) o Hazard and injury reporting o First aid o Training and induction o Record keeping (incl. register, documents to be displayed etc) • Health and safety requirements o Behaviour (link to worker code of conduct) o Dangerous good and hazardous substances o Electrical safety o Plant and equipment o Incidents (slips, falls, trips) o Drugs and alcohol o Vehicles o Personal protective equipment.

694. Workers code of conduct. The DB contractor will be expected, in advance of any construction work commencing on the project, to prepare and promulgate a code of conduct for its workers (and related visitors), including locals, other Samoans, and immigrants/expats. Induction training should include a cultural induction, delivered with the help of local knowledgeable elders.

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695. The DB contractor will be expected, in advance of any construction work commencing on the project, to promulgate this code of conduct for its workers (and related visitors), including locals, other Samoans, and immigrants/expats. Induction training shall include a cultural induction, delivered with the help of local knowledgeable elders.

696. The following is the worker code of conduct (WCC):

• Prior to entering a village or hamlet for the first time, the Chief, a leader from a church, or the head of a family (usually the father) shall be met for the construction contractor to show his respect. • All workers must always consult the Chiefs, and community leaders (such as a church pastor or an elder) about any issues that may not be clear in the local culture. • If no male members of the community are present, the outsider/visitor must not enter and talk to women, especially young girls and married women. This will help avoid any unnecessary arguments arising between a man and his wife or parents with their daughters. • When talking or shaking hands with someone (whether a man or woman) do not look straight at them in the eyes or press their hands strongly because to some it is disrespectful, shameful or could mean something different, especially to a woman. • Custom requires that visitors who enter a village are suitably attired. In particular, all genders should wear clothes that cover thighs. Do not criticize someone openly but always call the person aside and talk to him or her separately to avoid any ill feelings. Such incidents may even escalate to a stage where other relatives may become involved. • Saturdays and Sundays are days when some people in the communities go to Church and so there will be no work. Death and funerals are also times when work and other activities stop in the community. Always seek advice and clearance from the Chiefs or community leaders in such cases whether work should continue on or temporarily stop. • No alcohol or any form of drugs shall be consumed in the communities by any project employees. The contractor/developer should have and enforce an alcohol and drug-free policy (in the workplace, while driving vehicles, or use of the access roads). • All employees should respect the local custom or culture of the people. For example, one must always ask before taking any produce growing in the area, such as bananas, kumara, cassava/root crops, nuts, fruits from trees, and coconuts etc. There is always someone in the community who owns them. Picking something without asking first is regarded as disrespect for the owner, or stealing, and may require payment of compensation to the owner. • Workers and visitors should not make any disrespectful gestures or use any swearing words to anyone either in the community, or along the access road, especially to women or co-workers in the company workforce. These may lead to demand for compensation fees from communities. • No unlicensed person shall drive work vehicles. Drivers shall be tested prior to starting work on the project and have a valid license. • Construction company vehicles or trucks shall not be permitted to pick up anyone who is not an employee of the Project, except in case of an emergency. • Heavy machinery shall only be operated by those who have the license and proven skills to use those types of machines. This shall be embedded in the recruitment and other policies of the contractor/s. This will help avoid health and safety problems and the unnecessary destruction of property, resources, and cultural sites.

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• Workers and visitors shall drive slowly when passing villages that are very close to the access roadside or a pedestrian walking along the side of the road. • Drivers and passengers shall watch out for domesticated animals or people crossing the access road. • Take Prior Consultation, Careful Listening, and Paying Respect (PC-CL-PR) seriously because they are the key to avoiding conflict. Incidents can easily escalate into company/community conflicts.

697. Communicable diseases prevention and management plan. The purpose of the communicable diseases prevention and management plan (CDPMP) is twofold; firstly, it is to protect the health, safety and well-being of the communities within the project area; and secondly, it is to control disease vectors and pests namely mosquitoes and vermin.

698. The CDPMP will cover:

• Community health and safety o Health and safety impacts o Communicable diseases (incl. sexually transmitted infections and HIV/AIDS) o In-migration (links with the LWCMP) o Non communicable diseases due to changes to lifestyle leading to chronic conditions o Nutrition related diseases o Food security o Increased pressure on health care services o Site access and security (links with the SMP) o Management and mitigation measures o Approved service providers delivering awareness and prevention o Public awareness and prevention (link with SEP) • Disease vector management o Identify vectors, species and diseases o Methods to control vectors of disease o Identify triggers for treatments and types of treatment options o Review methods of vector management o Working with Ministry of Health o Increasing public awareness (links with SEP).

699. Traffic management plan. The traffic management plan (TMP) describes how the developer proposes to safely manage vehicular and pedestrian traffic during the preparation and construction phases of the project. The safety of road users and the effective management of traffic to and around the site is paramount to the successful day-to-day activities during the construction phase of the project.

700. The purpose of the TMP is to describe how the developer will implement the work in accordance with the requirements of the contract, specifications and EMP requirements, in addition to meeting national laws and regulations in respect of traffic safety.

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701. The TMP will cover:

• Key traffic management and safety issues (incl. safety and amenity of road users and on- site) • Traffic management responsibilities • Access road upgrading and new site road construction • Traffic control plans • Managing construction vehicle movement • Traffic and road user delay management • Traffic flow arrangements and control • Traffic control devices • Traffic controllers, plant and equipment • Information and awareness (links with SEP) • Emergency response (links with HSP and ERP).

702. Waste management plan. The waste management plan (WMP) will provide guidance on waste management in relation to construction activities and to understand what excess materials are likely to be generated and then focus on how the generation of those excess materials can either be avoided.

703. The WMP will cover:

• Waste streams - likely to be generated (by type and condition) and estimates of the approximate amounts of material (by type and condition) • Waste management options with a focus on waste avoidance/reduction • Opportunities to recycle and reuse • On-site management – segregation of wastes, selection of disposal sites and methods, how the waste management system will work on-site, including bin placement and access • Off-site management – selection of third-party waste management contractor who will provide services for the waste streams generated and data on waste/recycling generation • Transportation • Responsibilities – identification of those involved in relation to construction activities and WMP • Monitoring and evaluation.

704. Hazardous materials management plan. The hazardous materials management plan (HMMP) is to describe the procedures for storing, using, managing, and disposing of hazardous materials in a safe manner. The HMMP will describe the requirements under national laws and standards, EHSG, and international codes for hazardous materials.

705. The HMMP will cover:

• National laws and regulations and international best practice requirements • Hazardous materials inventory including: o Summary of storage and usage of chemicals and materials

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o Hazard class of chemical and material o Volume/amount of each hazard class and the container o Maximum allowable quantity (MAQ) o How the chemical/materials is to be used and stored (incl. labelling) • Identification of risk associated with hazardous chemicals and materials • Facility description and site plan that illustrates all buildings, roads, yards, outdoor chemical storage, sewers, wells, rivers and streams, and adjacent villages • Facility storage map that shows the location of: o All hazardous materials o All storage areas o Emergency equipment and exits o Evacuation points o Spot where designated individual will meet emergency personnel o All tanks/sumps/ piping • Accidental exposure measures • Emergency response (links with HSP and ERP) • Recording and reporting incidents.

706. Emergency response plan. The purpose of the spill prevention and emergency response plan (ERP) is to: (i) develop a proactive hazard identification system so as to prevent (or lower the likelihood) of spill events; (ii) establish the prevention measures and response process and responsibilities for managing these situations; and (iii) establish emergency response procedures.

707. The ERP will set out the requirements for management of unplanned spills of dangerous or hazardous materials during the project including spillages of: hydrocarbons (including diesel, petrol, greases, oils and other lubricants); drilling chemicals; hazardous chemicals); and, wastewater, including sewage.

708. The ERP will cover:

• Spill Prevention and Response o National laws and regulations and international best practice requirements o Spill response and containment strategies and capabilities o Framework for reducing the potential for spills o Sources of potential land contamination associated with construction o Sources of potential pollution of streams and rivers associated with construction o Categorize potential spill hazards o Training o Measures and process for rapid and efficient response to and manage hazardous material spills

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o Identify and document management measures to prevent, control and mitigate spill events o Responsibilities for implementing the management measures o Verification and monitoring and reporting measures o Monitoring operations to confirm that preventative measures are in place and followed • Emergency Response o Approach to emergency planning o Potential threats and emergencies (fire, landslide, trench/scaffold collapse, earthquake, tsunami and medical emergencies) o Incidents and emergencies o Evacuation procedures (including drills) o Communication protocols o Emergency control structures o Personnel and warden teams o Checklists and logs o Post-incident review procedures.

709. Air quality management and dust control plan. The purpose of the air quality management and dust control plan (AQMDCP) is to minimize: GHG emissions resulting from construction activities; impacts of dust generated due to the construction works; impacts of dust generated during transport of materials and other traffic; and, complaints from the community in relation to dust generated from construction activities.

710. The AQMDCP will cover:

• National laws and regulations and international best practice requirements • Air quality baseline and existing environment • Location and type of sensitive receptors • Criteria and performance standards • Identification of plant and activities that generate emissions • Identification of plant and activities that generate dust • Management, mitigation and control measures • Water spraying schedule • Monitoring and reporting.

711. Cultural heritage management plan. This EIA discusses the findings of the physical cultural resources assessment and concludes that it is unlikely that such resources will be adversely affected by the Project, but nevertheless, adopting the precautionary principle, the Project is committed to protecting physical and cultural resources within the project-affected area and will carry out additional, more detailed assessment of physical cultural resources as the Project develops.

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712. A short Cultural Heritage Management Plan (CHMP) will be prepared for the Project. The objective of the plan is to prevent any inadvertent loss of physical and cultural resources during project construction and operation.

713. The CHMP will describe the Chance Find Procedures (refer to Volume 2 - Annex F) that identify what measures will be taken to protect these cultural resources. The CHMP will also address measures to monitor any physical cultural sites that may be affected by on-going operation of the Project.

714. The CHMP will be in place two months prior to the commencement of construction works involving clearing and grubbing, or other land disturbing activities. This includes access roads, and main project site(s).

715. The DB Contractor will be responsible for the preparation and implementation of the CHMP, which will be reviewed by the Centre for Samoan Studies, National University of Samoa in addition to the PMU/CSC and ADB.

716. The CHMP will identify measures to be followed for both the construction and operation phases of the Project.

717. Forest clearance plan. The purpose of the forest clearance plan (FCP) is to clearly identify trees and vegetation to be removed by the project and trees and vegetation to be retained and protected. The FCP will be based on accurate and scaled maps and plans.

718. The FCP will cover:

• Elements of the BMMP and BOP with which it must be aligned • Responsibility for forest clearance (village groups, local contractor etc) • Demarcation of area on the ground (fencing etc) • Identification of trees (incl. drip-lines) to be protected • Site plans (showing cleared areas, protected trees, designated storage areas, areas to be cleared manually only etc) • Methods (machinery and manual clearance) • Notification to communities (links with SEP) • Schedule of forest clearance activities (avoiding wet season as much as possible) • On-going vegetation control measures • Re-use (mulch) and cut-timber collection by locals • Storage, transportation and disposal of cut timber • Sanctions for felling trees beyond footprint • Coordination with independent environmental expert • Recording of clearance activities • Monitoring and reporting.

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8.3.3 Environmental reporting requirements

719. The contractor will produce monthly reports and the CSC, on behalf of the PMU, will produce quarterly progress reports and these must include information on environmental performance. Reporting will include but not be limited to:

• Status of the implementation of the approved CEMP; • Status of any other contractor prepared environmental and social documents • Status of environmental, safety and labour permits (e.g. asphalt plant, borrow areas if appropriate) • Recording any environmental, health and safety and social monitoring results (e.g. air, noise, water quality, vibration audits / inspections) • Results of contractor and joint contractor and PMU/CSC site inspections and audits • Grievance redress mechanism • Accidents and incidents • Interaction with the public – public consultations and information disclosure and notices • Training of site staff in environmental, health and safety matters.

720. The PMU will prepare a semi-annual environmental monitoring report drawing on the contractor’s monthly and quarterly progress reports including environmental monitoring information and reporting the environmental and social performance of the project. This document will be disclosed on the ADB website.

8.4 Pre-Construction EMP

721. The pre- construction and design phase EMP (Table 8.1) is designed to assist the relevant parties of the environmental elements that have been identified in the EIA and need to be addressed in the preconstruction phase before the project moves into its implementation phase.

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Table 8.1: Environmental Management Plan – detailed design/pre-construction stage

Environmental Responsibility or social Ref Proposed Mitigation Measures Target / Indicator aspect/ Implementation Monitoring concern Overall contractor generated site and activity specific CEMP DD1 Development of Before any work commences on site the appointed contractor shall prepare a Preparation: PMU/CSC CEMP (and sub-plans) a contractor site and activity specific CEMP. The CEMP will contractor’s Supervising Engineer. approved by PMU/CSC generated describe the precise location of the required mitigation / monitoring, the persons environmental and Supervising Engineer social experts CEMP responsible for the mitigation / monitoring, and the schedule and reporting methodology. (ESE) define the boundaries of the Project and all works will have to be completed Review and within them. Marker posts will outline these boundaries within the Project area. clearance: include all of the sub-plans listed below unless these works are not scheduled to CSC, PMU, ADB start until a later date (see specific sub-plans for details) Approval: The CEMP will be submitted to the Engineer and PMU for approval at least 30 Supervising days before taking possession of any work site. No access to the site will be Engineer /PMU allowed until the CEMP is reviewed and cleared by CSC, PMU and ADB and approved by the Supervising Engineer. New topic specific or site-specific plans may also need to be developed by the contractor during the construction phase. These new plans will also need to be approved by the Supervising Engineer, and the PMU. The contractor will implement an EMS in line with national and international standards. The CEMP will include a review of the capacity of local emergency services. The contractor will also prepare a risk, GRM and accident and incident registers, which will include any specific plans/programmes required. DD2 Climate – The production of a Climate Resilience Management Plan will assist in PMU/CAC Confirmation of resilience. Resilience identification of an appropriate mechanism for management of climate resilience Specialist recruited Technical Advisor for Management risks, particularly those associated with adverse impacts of permanent works by DB contractor ADB Plan during the life of the project. Engineer/ PMU Ensure: that materials are adequately specified accounting for anticipated climate change. that the drainage system has sufficient capacity for intense rainfall events. that the works are protected against slope instabilities that substructures and foundations have sufficient resistance to changes in ground parameters that elements can be replaced at a later date by more resilient components DD3 Landscape and In the design, the designers will: Preparation: PMU/ Supervising Plan approved as part of Visual Avoid using non-native plant species. contractor Engineer. the CEMP by relevant parties.

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Environmental Responsibility or social Ref Proposed Mitigation Measures Target / Indicator aspect/ Implementation Monitoring concern Management Replace trees where lost as part of the Project (3 to 1 replacement ratio tbc). Approval: Information – included Plan Ensure new lighting does not result in light spill/ light pollution. Supervising in reports to the Choose colours of above ground sections of new buildings so they merge with Engineer, PMU Lenders. environment. Give priority to use of geotextile against shotcrete. Use irregular shape stones for rubble. Avoid use of white concrete. Where possible use lower lamp heights, provided it does not compromise safety aspects, such as the need to see road signs. To prevent future pollution issues, it is recommended that the use of sodium light bulbs is prohibited and that Light Emitting Diode (LED) lights are installed with a “neutral” colour temperature of 4000K. DD4 Critical habitat – The CEMP will be aligned with relevant elements of the BMMP and BOP; Preparation: DB PMU/ Supervising Targets specified in BMMP protection (1) Implement the following mitigation measures to reducing the most significant contractor (with Engineer. and BOP; impacts on critical habitat. Contract documents to require contractor to: specialist inputs as Information – included Information included in • Implement a strict code of conduct forbidding hunting/trapping, and required) in reports to ADB contract documents purchase of wildlife, with heavy penalties. Train all site personnel on Approval: PMU, this code of conduct, and its justification; ADB, MNRE • Prior to any clearance, identify, clearly mark and map all mature native trees, to facilitate avoidance and minimization • As per the approved forest clearance plan (FCP), minimize clearance of native vegetation at the Project site and around associated roads and other infrastructure; using already cleared or modified areas for construction wherever possible. Prioritize avoidance of Ficus and Dysoxylum trees (which may provide seasonal food sources for Tooth-billed Pigeon), and attempt to relocate any of these which cannot be avoided; • Replant native vegetation (including Dysoxylum species) in any temporarily disturbed areas; • Regularly maintain and inspect/certificate all vehicles, equipment and machinery to ensure that noise levels conform to national standards; • Avoid construction during the most sensitive Mao breeding period (June-August inclusive); • Avoid construction within 150 m of an occupied Tooth-billed Pigeon or Mao nest; • Educate site staff on the dangers of deliberate introductions of invasive species. DD5 Critical habitat – In the detailed design and planning include measures to: Preparation: PMU/ Supervising Information included in protection (2) Install staffed access control on new roads, allowing access to no-one except Engineer, Engineer. Contract documents operational staff, or government officials; Approval: PMU

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Environmental Responsibility or social Ref Proposed Mitigation Measures Target / Indicator aspect/ Implementation Monitoring concern Engage and educate the local community, including providing incentives to Information – included conserve priority biodiversity - such as employment in restoration, invasive in reports to ADB species control and monitoring; Take care to avoid introduction of new invasive species to, and spread of existing invasive species within, the Project area Prior to finalization of project designs and any clearance, identify, clearly mark and map all mature native trees, to facilitate avoidance and minimization Educate local people on the dangers of deliberate introductions of invasive species. DD6 Critical habitat – Restore up to 240 ha of forest elsewhere in the Vaisigano River watershed; Preparation: BMMP PMU/ Supervising As per BMMP and BOP offsetting Support translocation of some Mao to American Samoa and BOP Engineer / MNRE. residual impact specialists Information – included Approval: MNRE, in reports to ADB ADB DD7 Environmental EPC to develop operating procedures to release a permanent baseflow from Preparation: PMU/ Supervising Included in Operational Flow Samasoni Weir and from the offtake weir on the middle branch to restore Engineer, EPC Engineer / MNRE Management procedures of permanent aquatic habitat to 4.2 kilometres of the main channel downstream PMU Information – included EPC from the Samasoni Weir and the final 1.3 kilometre reach of the middle branch Approval: EPC / in reports to the before it joins the west branch. A monthly fresh rule is proposed from these MNRE Lenders locations to increase the frequency and duration that higher flows are delivered downstream Install a fish ladder and syphon-like structure above at Samsoni weir to facilitate fish passage

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8.5 Construction Phase EMP

722. An overarching EMP has been developed for the construction phase of the Project. This identifies the need for a contractor developed CEMP and supporting sub-plans and site-specific plans to manage specific issues or activities. The EMP in this EIA is set out to assist the contractor in preparing their CEMP. It clearly identifies the environmental elements that need to be addressed and presented in sub-plans to the contractor CEMP.

723. The relationships between these plans is presented in Figure 8.2 and the construction phase EMP is presented in Table 8.3. To assist the contractor in preparing the CEMP, Table 8.2 sets out a contents list that could be considered and Figure 8.3 identifies all the sub-plans identified in this EIA that should be included in the CEMP.

Figure 8.2: How a contractor’s CEMP evolves from the EIA and EMP

Contract EIA Disclosed on ADB website By Contractor By Client Environmental For client by specialist Impact Assessment

Environmental Management Plan

Contractor Generated - Site Specific Environmental Management Plan (SEMP)

Four Sub Plans - Engineering Aspects

Off Camp Operations Inside Camp Operations Construction Dam Construction Plant Operation Workshop Camp Management Plan Management Plan Management Plan Management Plan

Ten Contractor Supporting Plans - Environmental Aspects Environmental Indicators

Water Air Pollution Noise Control Waste Soil Site Drainage Ecology biodiversity management Management Indicators and monitoring Borrow Pit Cultural & Archaeological Find Grievance Redress Mechanism plan (BMMP)

Checklists Site Specific Checklists Camp Checklists

Dam Camp - Manufacturing Camp (Operation, Borrow Pits construction Areas (Processing, Management & crushing / concrete) Community)

Ecology Indicators

Checklists used on site for daily / weekly / monthly checking of Environmental Conformity

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Figure 8.3: All of the subplans for the CEMP identified in this EIA document

Environmental Impact Assessment (EIA) Environmental Management Plan (EMP) Table 44 within EIA

Contractor Generated Site Specific Environmental Management Plan (SEMP) Administration Management Plans Plans (EPC/ PMU)

# EMP ref: Topic Specific Management Plans # EMP ref: Activity Specific Management Plans # EMP ref: Community Protection Management Plans 1 5 The Waste and Materials Management Plan (WMMP) 1 21 Traffic Management Plan (TMP) 1 12 Climate Resilience Management Plan 5a Spoil Disposal Plan 2 22 Health and Safety Plan 2 14 Stakeholder Engagement Plan 5b Asbestos Management Plan 22a • Specific measures for the construction of bridges and tunnels 3 16 Grievance Redress Mechanisms (GRM) 2 6 Soil, Erosion and Topsoil Management Plan 22b • Health Plan 5 18 Social, Community and Health Review 3 7 Water Resources Management Plan 3 23 Emergency Response Plan 6 19 Labour and Working Conditions Management Plan (LWCMP) 7a • Ground Water Management 23a • Natural Disaster Response 19a • Local Employment and Procurement Plan (LEPP) 7b • Waste Water Management 23b • Spill Management Plan 19b • Social Risk Register 4 8 Air Quality Management Plan 4 24 Camp Management Plan 19c • Gender Action Plan 5 9 Noise and Vibration Management Plan (NVMP) 5 25 Concrete Production Management Plans 9a • Pre-Commencement Condition Surveys 6 26 Construction plans and Method Statements 6 10 Cultural Heritage Management Plan 7 27 Method Statements for Temporary Activities 10a • Chance Find Procedure 8 28 Blasting Management Plan 7 11 Biodiversity Management Plan (BMP) 28a • Tunnel specific measures 11a Avifauna Management and Monitoring Plan (AMMP) 9 29 Construction Road Access Management Plan 8 13 Landscape and Visual Management Plan 9 15 Contractor Stakeholder Engagement Plan (CSEP) 10 17 Workers Code of Conduct (CoC)

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Table 8.2: Provisional contents list for CEMP and guidance notes on provisions

Main headings Sub-headings Guidance notes on section contents A brief description describing the purpose of the document. This section may include the company INTRODUCTION environmental policy. Outline of the EMS developed for the Project ENVIRONMENTAL The contractor organization policy / principles on environmental protection designed to minimize the negative

POLICY effects of its activities on the environment and community. Including: an organization chart showing the interactions between the different members of the site team from the MANAGEMENT Project Manager (or Similar) through the site supervisors / engineers, surveyors and the labour force. The RESPONSIBILITIES environmental team must report directly to the Project Manager, not through site supervisors / engineers. Job descriptions setting out the role and responsibility of each post in terms of environmental and social safeguards Emergency contact numbers and procedures – including contacts in the local community PROJECT To confirm the contractor understanding of the extent of their environmental and social safeguard

DESCRIPTION responsibilities Project Area Demarcating construction camps, manufacturing areas, works areas, laydowns, spoil disposal sites, etc and

sensitive uses including villages, springs and water courses susceptible to impact from the works. Must include suitably detailed location plans for construction camps, Site offices (administration) , Project Details Manufacturing areas, Material Storage and Laydown Area. The plans must identify elements such as

canteens, ablution blocks, drainage layouts, septic tanks, waste management (disposal bins) TRAINING Specific training that will be given to site personnel PPE The correct use of PPE Spills How to deal with spills Waste management Including reuse and recycling and waste separation Communicable diseases To be delivered by approved service provider recruited by the contractor Particularly for expatriate staff on acceptance / understanding of national cultural differences and governing Worker code of conduct behaviour relative to: fraternization; conduct in villages; behaviour around women and children; penalties/sanctions on worker alcohol and/or drug use RELEVANT Extracted from relevant sections of EIA LEGISLATION ENVIRONMENTAL The specific plans for environmental management that have been identified in the EMP of the EIA MANAGEMENT PLANS ENVIRONMENTAL Listing the environmental and social safeguards reports that the contractor will be producing during the MONITORING & project. EIA identifies monthly and quarterly reports REPORTING Instrumental Monitoring Identifying environmental monitoring that will be carried out Identifying the site and activity specific forms the contractor will use to confirm compliance with environmental Site audits and checklists requirements

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Main headings Sub-headings Guidance notes on section contents Public Consultation How the contractor will set up and manage a formal set of meetings with the community and any ad hoc

Schedule meetings How complaints will be dealt with at site level identifying who is responsible and how a complaint is escalated Grievance Redress through the stakeholders (preferably with a flow chart).

Mechanism (GRM) Complaints hotline Community notice board with contacts

Note that this table is presented for guidance only. It is the contractor’s responsibility to produce a CEMP based on their approach, program and site activities (working methods) that will achieve the necessary compliance with environmental obligations in the contract. The PMU, supported by the supervision consultant and ADB will review and approved the CEMP prior to any construction activities, including investigations and site clearance, taking place.

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Table 8.3: Environmental Management Plan – construction stage

Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring C1 Development, review The contractor shall prepare a CEMP. The CEMP will Preparation: PMU/Supervising CEMP approved by and approval of describe the precise location of the required mitigation / monitoring, the contractor’s Engineer. PMU/Supervising contractor’s persons responsible for the mitigation / monitoring, and the schedule and Environmental and Engineer generated CEMP reporting methodology. Social Experts including sub-plans define the boundaries of the Project and all works will have to be completed (ESE) and site-specific within them. Marker posts will outline these boundaries within the Project Approval: plans area. Supervising include all of the sub-plans listed below unless these works are not Engineer PMU scheduled to start until a later date (see specific sub-plans for details) The CEMP will be submitted to the Engineer and PMU for approval at least 30 days before taking possession of any work site. No access to the site will be allowed until the CEMP is approved by the Supervising Engineer, and the PMU. New topic specific or site specific ESMPs may also need to be developed by the contractor during the construction phase. These new plans will also need to be approved by the Supervising Engineer, and the PMU. The contractor will implement an ESMS in line with national and international EHSS Standards. The CEMP will include a review of the capacity of local emergency services. The contractor will also prepare a Social Risk Register, which will include any specific plans/programmes required as a result of the Community and Health Review. C2 Development of sub- Adopt the relevant findings of the BMMP and BOP and ensure CEMP and Preparation: DB Supervising Plans prepared in line with plans sub-plans align with those documents; contractor Engineer/PMU and Section 8.3.2 and any Sub-plans developed as per EIA Section 8.3.2; Review and EPC (where additional outline agreed Prior to start of site works, the contractor shall prepare the following plans in clearance: appropriate) with CSC, PMU and ADB; line with the environmental and social requirements: PMU, CSC, ADB Plans approved as part of Waste and Materials Management Plan (WMMP), including: Approval: the CEMP by relevant parties. Spoil Disposal Plan Supervising

Asbestos Management Plan Engineer and PMU Soil, Erosion and Topsoil Management Plan Water Resources Management Plan, including: ground Water Management and wastewater Management Air Quality Management Plan (AQMP) Noise and Vibration Management Plan (NVMP) for access road, including: Pre-Commencement Condition Surveys Cultural Heritage Management Plan, including chance find procedure

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring Construction Climate Resilience Management Plan Landscape and Visual Management Plan Forest Clearance Plan (FCP) Stakeholder Engagement Plan (SEP), including GRM Workers Code of Conduct (WCC) Labour and Working Conditions Management Plan (LWCMP), including: Local Employment and Procurement Plan (LEPP) Traffic Management Plan (TMP) Health and Safety Plan, including: Specific measures for the construction of bridges and tunnels Emergency Response Plan, including: Natural Disaster Response Plan Spill Management Plan Camp Management Plan Concrete Production Management Plans Construction plans and Method Statements, including: Method Statements for Temporary Activities, including: Storage Areas Manufacturing Areas Roads / Access Roads Blasting Management Plan (if needed), C3 Obtaining All necessary licences and permits must relation to environmental, safety DB contractor PMU, PUMA Copies of licences, development and labour must be obtained prior to starting the activity that they apply to. Approval: PUMA, Information – included permits and agreements. consents, licences, A database tracking all permits and consents shall be developed and MNRE in reports to the permits and maintained. Lenders agreement Maximum allowable concentration of substances discharged into the surface water body must be agreed with MNRE approved by the CEP. Volume of water abstraction, and sources, must be agreed with the CEP. C4 Sub-contractors The contractor shall ensure that: Supervision All plans and contracts Copies of sub-contractor Provisions will be incorporated into all subcontracts to ensure the Engineer/ PMU approved by the agreements. compliance with lender requirements, Samoan legislation and the EMP and relevant parties. its associated sub-plans at all tiers of the sub-contracting. Information – included All environmental, social and safety requirements for the contractor will in reports to the apply to the sub- contractors. This will be secured via contracts. It is the Lenders. responsibility of the contractor to audit sub-contractors and ensure compliance.

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring All Project sub-contractors will be supplied with copies of the EMP, and sub plans. All relevant requirements of the EMP and sub-plans must be communicated to sub-contractors. All subcontractors will be required to appoint a safety representative who will be available on the Site throughout the operational period of the respective subcontract, unless the Supervision Engineers approval for the contractor’s safety representative to undertake take this role, is given in writing. C11 Biodiversity The CSC will engage a suitable number of suitably qualified terrestrial Terrestrial ecologist MNRE, PMU, ADB BMP Plan approved as Management Plan ecology and avifauna specialists to map the site and confirm that the site is and avifauna CSC, Supervising part of the CEMP by (BMP) clear of biodiversity constraints, in advance of construction works. specialist recruited Engineer. relevant parties. They should include identification of areas of greatest ecological value, by CSC Information – included Annual reporting on BMP features/species needing translocation, bird nesting areas where schedules in reports to ADB actions / monitoring need to be altered, etc. Their responsibility will include both surveys to BMMP and BOP outcomes. inform the development of additional mitigation (if required) such as Mao preparation: Training Records and bat surveys and other species-specific surveys, and surveys to help Recruited ensure that specific mitigation is applied within the project area in advance specialists of vegetation clearance. Approval: The terrestrial ecologist and avifauna specialist with report directly to the Supervision Engineer who will instruct stop work notices as required by the ADB, MNRE terrestrial ecologist and avifauna specialist. The contractor will ensure that the CEMP and sub-plans are fully aligned CEMP and BMP with the BMMP, AMMP (see below) and BOP. The CEMP will include a Approval: Engineer, Biodiversity Management Plan—prepared by a suitably qualified ecologist PMU, ADB engaged by the contractor—covering actions to safeguard, conservation of biodiversity on the influence territories or specific sites that could be affected due to the planned construction activity. Compliance with the plan will be responsibility of contractor and EMO. The plan will set out the requirement to Mark and keep to the boundaries of the project area and the temporary sites. No removal of vegetation outside the mentioned boundaries. Prohibit shortcuts by workers, pedestrians and vehicles to avoid impact on the vegetation. Reinstate disturbed sites immediately after completion of works. Restore vegetated areas with diverse plants/seed mix of local/regional provenance. Prohibit use of herbicides/chemical during vegetation clearance. Brief the staff in vegetation protection issues during site induction.

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring Brief staff in relation to biosecurity measures (in particular invasive species). The BMP will also include specific actions to be implemented through the construction phase of the project to further enhancement of biodiversity in the area. These actions will have associated monitoring commitments to ensure term effectiveness/relevance. Preserve vegetation in the areas outside the boundaries of the project sites. Adhere to no horn policy to avoid disturbance of wildlife. Impose speed limits on access roads for project vehicles to minimise risk of road kills. Fence trenches or pits to avoid entrapping and injuries of the fauna species. Bright coloured ribbons may be used for big animals (e.g. cattle), while metal plastic and other shields/fences may be used for small animals. Upon completion of the shift put planks or medium size twigs in the trenches to allow small animals to escape. Check pits and trenches prior to filling up. Unless advised otherwise by the Supervision Engineer, tree-felling should be timed to avoid bat roosting and bird nesting seasons. Where a tree is identified as having the potential to support such features, felling/removal should only take place between December and March. In case bat roosts are found, arrangement of bat boxes can be considered as mitigation measure. Implement tree felling/house demolition works from December to March to avoid impact on bats and breeding birds (nesting/hatching). Where relevant, implement monitoring of water quality (visual detection of turbidity increase, analysis - upstream and downstream of the worksite). Implement mitigation measures set for preservation of water quality and bank erosion (soil stability). All staff to comply with the WCC The BMP will be linked to the Landscape Management Plan, with regards to land restoration and selection of suitable species. Avifauna The measures identified in the Avifauna Management and Monitoring Plan AMMP preparation: AMMP: PMU/ AMMP reflected in BMP, Management and (AMMP) will be fully reflected in the contractor’s BMP, CEMP, FCP and BMMP specialists Supervising Engineer. FCP and approved as part Monitoring Plan other sub-plans as relevant. Approval: Information – included of the CEMP by relevant (AMMP) as part of The AMMP will include: in reports to ADB parties. BMMP PMU, CSC, MNRE, Details of a survey plan prior to construction, during the works, and post- ADB Annual reporting on construction, it would also include a survey for mao and manumea AMMP actions / Implementation: distribution within the entire catchment. This is to determine the distribution monitoring outcomes. and abundance of birds and to monitor the overall impact of development Specialists, Training Records on these species. DB contractor For in the breeding seasons prior to construction commencement, during the works, and post-construction, undertake a comprehensive pest control

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring programme, focussing on three species- rats, cats and pigs. For mao reducing rat numbers and protecting nests (through trapping and steel ringing trees), reproductive success and adult and fledgling survival will be increased. This will lead to increased recruitment and could offset some of the effects of the proposed development. Reducing numbers all three pest species is likely to be beneficial for Manumea since it will increase fruiting availability and potentially increasing reproductive success. Other passerine species of concern will also be positively affected with increased reproductive success by pest control, especially as a result of rat targeted control. Vegetation clearance should be conducted at the beginning of the dry season and outside of the main nesting period for mao (June to October) No construction activity or vegetation clearance should occur within 150 metres from an occupied nest of an endangered or critically endangered species. Engagement and education of the local community. This could include the employment of members of the community in planting, pest control and monitoring activities, providing an economic incentive to protect the birds. In areas buffering the site habitat enhancement should also occur by reducing invasive trees e.g. rubber trees. C12 Climate – Resilience The Climate Resilience Management Plan will ensure an appropriate Engineer/ PMU PMU/ Technical Confirmation of resilience. Management Plan mechanism for management of climate resilience risks, particularly those Advisor for ADB associated with adverse impacts of temporary works on permanent works during construction. Ensure: compliance with the to ensure that the temporary works (e.g. access roads) do not decrease climate resilience of permanent works as contained in the tender specification that surfacing materials are adequately specified accounting for anticipated climate change. that the drainage system has sufficient capacity for intense rainfall events. that the works are protected against slope instabilities that substructures and foundations have sufficient resistance to changes in ground parameters that elements can be replaced at a later date but more resilience components C13 Landscape and The Landscape and Visual Management Plan will outline the need to. Preparation: PMU/ Supervising Plan approved as part of Visual Management Use low wattage lamps directing light downwards at work sites and camps. DBcontractor Engineer. the CEMP by relevant Plan parties.

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring Ensure all lighting related to construction activities shall be shielded or Approval: Information – included PR1, PR2, PR6 directed to restrict any direct illumination onto property located outside of Supervising in reports to the the Project Site boundaries. Engineer, PMU Lenders. All construction site lighting shall be turned off when construction activities have ceased for the day. Community Liaison, Labour and Safety Management Sub Plans C14 Disclosure of project Implement the Stakeholder Engagement Plan (SEP) and organise regular Project MNRE, Technical information and consultation activities with local communities. Implementation Unit Advisor for ADB community A Community Liaison Officer (CLO) shall be appointed to manage (PMU), Project consultation consultations and implement the developed Stakeholder Engagement Plan Management and Stakeholder (SEP) with local communities. Supervision Consultant, if Engagement Plan Organise consultation events for men, women and children and disclose information about the construction impacts, health and safety, scheduling appointed and timeframes. The project design Conduct a meaningful consultation with the affected vulnerable groups to team if available identify a best solution to improve their livelihood; or provide an alternative living area for them. Focus groups are preferred methods for engagement with this group. Separate males and females focus group discussions should be conducted. In particular, women must be consulted on construction and road safety, and given fair and equal representation of women in decision-making situations and greater awareness of road safety from a perspective. Data to be collected on construction from a gender perspective in the region and results communicated. Develop outreach and campaign promoting gender safety. This includes focusing on risks for women and children through an enhanced approach to safety inclusive of security dimensions and understanding masculinities and men’s behaviours in relation to safety so as to better target potential campaigns. Provide regular updates on the Project website and at Project milestones. If required, engage the media in disseminating Project information and manage public relations in case of NGO interest. Update SEP on annual basis throughout the Project. C15 Contractor Prior to start of site works, the contractor shall, based on the Project’s SEP: Preparation: PMU, Technical GRM Established. Stakeholder Develop and maintain a contractor SEP (CSEP) aligned with the contractor Advisor for ADB 24-Hour hotline Engagement Plan overarching Project plan and train workers in the grievance redress Review, ADB, PMU Information – included established and (CSEP) mechanism (GRM) requirements; (incl. CSC) in reports to the operational. Lenders. Notice boards located at construction sites.

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring Establish and communicate a GRM, as described in the EIA disclosure Approval - PMU, Consultation completed package, to communities in the project impact zone, building on the GRM in Supervising with the identified the SEP; Engineer. stakeholders as per the Set-up and publicise a 24-hour hotline for complaints and maintain a GRM SEP and CSEP. registry which identifies resolution and close-out actions and dates; ensure that names and contact numbers of CLOs within the PMU, villages and within the PMU contractors organisation are placed on the notice boards outside the construction site; complete on-going consultation with men, women and children during construction; and Keep a log of all complaints received. The plan will outline the need to repair community facilities if damaged as a result of the works as soon as practicable. contractor SEP to be updated on annual basis throughout the Project. C16 Grievance redress Prior to start of works, the contractor shall: PMU responsible for Technical Advisor for GRM Established. mechanisms Establish and communicate a Grievance Redress Mechanisms (GRM), as contractor ADB 24-Hour hotline described in the EIA and their own CSEP, to communities in the project PMU established and impact zone and to their worker and sub-contractors. Information – included operational. Set-up and publicise a 24-hour hotline for complaints in reports to the Notice boards located at Ensure that names, genders and contact numbers of representatives of the Lenders. construction sites. PMU and contractors are placed on the notice boards outside the Consultation completed construction site. with the identified stakeholders per the SEP. C17 Worker code of The contractor shall prepare a worker code of conduct (WCC) that Preparation: DB PMU Completion and approval conduct (WCC) enshrines the commitment of the project to meet Lenders employment and contractor, village Information – included of WCC; labour standards. Environmental and social protection and anti-bribery and leaders in reports to ADB Monitored implementation corruption controls. Approval: PMU, of WCC Ensure measures outlined in specific management plans (Biodiversity CSC, ADB Management Plan, Waste and Materials Management, Water Resources Implementation: Management Plan etc) are referenced within the WCC. DB contractor All workers will be briefed on the Code of Conduct at the moment of recruitment, explaining ways of monitoring and consequences in case of violation. Measures to include: Appropriate attire for men and women – for health and safety and cultural reasons Community relations and sensitivities Hygiene/ Health Rules related to alcohol and drug use; Equal opportunities and gender-sensitive conduct

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring Banned activities – no hunting/ poaching, no picking of berries / fruit / seeds or medicinal herbs Non discrimination Special attention will be given to the prevention of gender-based violence and the promotion of a gender-sensitive working environment on construction sites, in line with the Local Employment Plan (LEP) and attached Gender Action Plan (GAP). A specific training session will be delivered on the Code of Conduct provisions on sexual harassment, abuse and exploitation at the moment of induction. C19 Labour and Working The Labour and Working Conditions Management Plan (LWCMP) will Supervising Safety induction Samoan Labour Laws Conditions include: Engineer/ PMU, completed. International Labour Management Plan policy/legal framework information (including labour and OHS requirements Information – 24-hour hotline Organisation (ILO) (LWCMP) of national legislation and EBRD Performance Requirements), included in reports operational. requirements Including – contractor’s human resource policy statement; to the Lenders. Regular training Local Employment workforce induction and training; contractor Code of provided. and Procurement information on labour rights, and establishment of a worker’s organisation in Conduct No findings in the Plan (LEPP) the project area to allow for the potential for collective bargaining; Labour audit. labour audit. Social Risk Register prevention of child and forced labour; Complaints log. GRM Established. Gender Action Plan equal opportunities and non-discrimination, and how this will be applied for all workforce; management of impacts associated with migrant workers, Measures to counter the potential risk of Gender Based Violence (GBV) (with reference to the Code of Conduct); Rules related to alcohol and drug use; worker accommodation requirements, non-employee worker gaps workforce grievance mechanism, sourcing and management of security personnel (with reference to the Voluntary Principles on Security and Human Rights33), and other matters as required Conduct induction training for all workers prior to the start of civil works, in a language(s) and format easily understood by the workforce. The workforce Induction and documentation should specifically include: worker rights and responsibilities, including the worker grievance procedure, cultural context induction, and interaction/engagement with community members. The

33 https://www.voluntaryprinciples.org/

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring induction needs to apply for all workers (anyone working on the project site). The contractor needs to ensure that the core labour requirements are cascaded down across the entire contracting chains, including sub- contractors and suppliers of core materials. The LWCMP will tie in with the Grievance Redress Mechanism (GRM). The LEPP will describe the measures to be taken to promote local procurement and employment. Key actions will include processes and commitments to: Maximise number of local people employed in pre-construction and construction works (both men and women). Maximise goods and services sourced from local commercial enterprises. The need for work conditions to be competitive but comparable to equivalent employers, including equal pay for equal work by migrant workers (e.g. construction force labourers that may be engaged); The engineer / PMU will undertake a labour audit during the first month of the construction phase to confirm compliance with the Labour Standards identified above. The contractor will supply and/or employ workers with appropriate skills / competencies and qualifications. The Gender Action Plan (GAP) will complement the LEPP and describe affirmative measures to be taken to promote women in construction and gender-sensitive construction practices. Key actions will include processes and commitments to: The prevention of any form of gender-based violence, including sexual harassment (in line with the Code of Conduct), including through the provision of explanatory sessions on the anti-harassment policy to all new and existing workers, The development of concrete, affirmative measures, in collaboration with PMU and the Lenders, to increase the number of women in specific positions through active local recruitment campaigns and outreach to VET institutions and Faculties of Engineering, The provision of adequate working conditions and Personal Protective Equipment (PPE) to workers of both sexes - customised by anthropometric specifications of women and men workers. The need for work conditions to provide a safe, secure and equal environment for men and women, including separate toilets for male and female workers with access to water and soap close to the actual places where women work, installation of lighting inside toilets and in the area through which women access these facilities, provision of adequate premises where women can get ready before starting work (i.e. accessible

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring and clean places equipped with changing room and a toilet, in a facility that is well-illuminated, adequate lighting on site at night; The promotion of gender-responsive external communications, including through presentation of men and women road workers in visual PR and communications materials (from recruitment to delivery of the Project), consistent usage of images to represent the entire client base services (e.g. women and men of local communities benefiting from road construction and maintenance); use of non-sexist, gender-sensitive language, the respectful non-sexualised depiction of women, and provision of female role models based on women’s competence and professional skills in all public presentations, print and media, for local employment recruitment and other campaigns; The maintenance of relationships with relevant community groups (especially women’s groups); The establishment of a system for monitoring the Gender Action Plan. C23 Emergency Develop and implement emergency preparedness and response plans Preparation: PMU/ Supervising Plan approved as part of Response Plan (ERP) for each Project package. These should include measures for contractor Engineer. the CEMP by relevant Including – prevention, mitigation and response to emergency scenarios, at a minimum Approval: Engineer Information – included parties. Natural Disaster covering: and PMU, in reports to the Response Road and traffic accidents; Lenders. Spill Management Other accidents and injuries; Plan spills of hazardous substances; fire; natural disasters (earthquake, landslip, flood, extreme weather events, etc.); accidents during tunnelling (e.g., tunnel collapse, tunnel fires, gas release, etc.). The ERP should describe: Roles and responsibilities for prevention and response Procedures for responding to different scenarios (fire, flood, traffic accident, etc.) Resources required (personnel and equipment) and how these will be provided and maintained. This must consider delays to emergency response services, due to the current condition of the road Competence and training requirements The Spill Management Plan will include procedures, responsibilities, resources, documentation and reporting requirements, training provisions for relevant staff, etc. to avoid spills of hazardous substances and to effectively respond to such incidents. All refuelling activities must occur on hard surfacing.

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring Provide first aid facilities that are readily accessible by emergency response personnel and workers. Provide firefighting equipment at the work areas, as appropriate, and at construction camps. The ERP must be regularly reviewed and updated – as a minimum annually and after any emergencies or accidents. Activity Specific Sub-Plans C24 Camp Management Prior to start of site works, an Environmental and Social Screening of Preparation: PMU/ Supervising Plan approved as part of Plan potential camp locations prior to construction, to identify any sensitive contractor Engineer. the CEMP by relevant environmental receptors and to ensure the camps are sufficient distance Approval: Engineer, Information – included parties. from villages and local communities. Consultation with local communities PMU in reports to the before the construction camp is developed is required, covering Lenders Location of camps over one kilometre from any residential area and at least 50 m from any surface watercourse and not within 2 km of a protected area – any deviation from these separation distance must be supported by sufficient justification and additional mitigation measures, and the location and mitigations must be approved; Coordination of all construction camp activities with neighbouring land uses; confirmation as to whether workers can be accompanied by families or whether rosters will enable locally engaged workers to go home daily or not. Prior to start of site works, the contractor shall develop a Camp Management Plan. This will include: Ensuring that workers’ accommodation/ construction camps is designed and managed in compliance with guidance on workers’ accommodation; layout of the site, including location of temporary specifications for storage areas for waste, equipment maintenance areas, lubricant and fuel storage sites with indication of the distance from watercourses and other sensitive receptors description of sewage management activities, including treatment, monitoring and effluent disposal processes; description of waste management activities, including waste minimisation, and storage and disposal processes for each waste stream; community relations, restriction of access to camp and facilities, induction briefing on camp rules and local issues/sensitivities, camp rules (such as restrictions on; alcohol, drugs use, discipline, noisy activities, community liaison, no poaching, environmental protection measures applicable to the camp site, decommissioning and re-cultivation, etc.), and workers welfare The construction camps will be staffed and equipped with a health clinic for all workers.

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring The contractor will be responsible for maintenance and clean-up of campsites and respecting the rights of local land users. The Camp Management Plan will indicate the system proposed and the locations of related facilities in the site, including latrines, showers, canteen, recreation facilities, laboratories, maintenance areas, etc. The plan will cover camp sites as well as any sites considered as associated facilities, and will require IFI consideration, due diligence and approval. The plan will cover camp sites as well as any sites considered as associated facilities, and will require ADB consideration, due diligence and approval. The plan will cross reference other sub-plans including; Water Resources Management Plan, Spill Management Plan, Air Quality Management Plan, Noise and Vibration Management Plan, Waste and Materials Management Plan, and others as required. C25 Concrete Production Prior to start of site works, the contractor shall develop a Concrete Preparation: PMU/ Supervising Plan approved as part of Management Plans Production Management Plan. This will include: contractor Engineer the CEMP by relevant Describing the layout and management of concrete batching plant including: Approval: Engineer, Information – included parties. Location, hours of use, water discharge, noise and vibration management PMU in reports to the and dust control. Lenders. Batching plants will be located downwind of residential areas and not within 1 km of any residential area. The entire batching area traversed by vehicles – including driveways leading into and out of the area – will be paved with a hard, impervious material. Sand and aggregates will be delivered in a dampened state, using covered trucks. If the materials dry out during transit they will be covered to avoid creation of dust. Sand and aggregates will be stored in a hopper or bunker which shields the materials from winds. The bunker should enclose the stockpile on three sides. The walls should extend 1 m above the height of the maximum quantity of raw material kept on site and extend 2 m beyond the front of the stockpile. The hopper or bunker will be fitted with water sprays which keep the stored material damp at all times. Monitor the water content of the stockpile to ensure it is maintained in a damp condition. Overhead storage bins will be totally enclosed. The swivel chute area and transfer point from the conveyor will also be enclosed. Rubber curtain seals may be needed to protect the opening of the overhead bin from winds.

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring Conveyor belts which are exposed to the wind and used for raw material transfer will be effectively enclosed, to ensure dust is not blown off the conveyor during transit. Conveyor transfer points and hopper discharge areas will be fully enclosed. Conveyor belts will be fitted with belt cleaners on the return side of the belt. Weigh hoppers at front end loader plants will be roofed and have weigh hoppers shrouded on three sides, to protect the contents from the wind. The raw materials transferred by the front-end loader should be damp, as they are taken from a dampened stockpile. Store cement in sealed, dust-tight storage silos. All hatches, inspection points and duct work will be dust-tight. Silos will be equipped with a high-level sensor alarm and an automatic delivery shut-down switch to prevent overfilling. Cement dust from the silo during filling operations must be minimised. A fabric filter dust collector will be used. The cement weigh hopper will be enclosed, to ensure that dust cannot escape. An inspection of all dust control components will be performed regularly – for example, at least weekly. The plan will cross reference other sub-plans including; Water Resources Management Plan, Spill Management Plan, Air Quality Management Plan, Noise and Vibration Management Plan, Waste and Materials Management Plan, and others as required. 26 Construction plans The contractor will be responsible for preparing method statements for all Preparation: PMU/ Supervising Plans approved 14 days and Method work activities and infrastructure including establishment, operation and contractor Engineer prior to commencement of Statements reinstatement. Approval: Information – included works in these areas. All Construction Plans will cross reference relevant; environmental, social Supervising in reports to the and health and safety sub-plans. Engineer, PMU Lenders 27 Method Statements The contractor will be responsible for preparing a method statement for any Preparation: PMU/ Supervising Statement approved 14 for Temporary temporary activities and infrastructure (e.g. temporary roads, temporary contractor Engineer days prior to Activities river crossings, temporary storage areas), including establishment, Approval: Engineer, Information – included commencement of works operation and reinstatement of the facilities. PMU in reports to the in these areas. Lenders 28 Blasting The Contactor must appoint an authorised blasting contractor. Preparation: PMU/ Supervising Plan approved as part of Management Plan The contractor must audit suppliers, ensure all approvals and authorisations contractor Engineer. the CEMP by relevant (If required) are in place and good practices are applied in line with international practice Information – included parties. ahead of blasting works in reports to the Methodology for the management of control of tunnel blasting including Lenders. methods for noise and air quality management and occupational and community health and safety.

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Environmental or Responsibility Ref social aspect/ Proposed Mitigation Measures Target / Indicator concern Implementation Monitoring Blasting will be scheduled during the day only. Approval: Communities (within the area impacted by blasting related impacts) will be Supervising informed of blasting timetable in advance and will be provided adequate Engineer, PMU notice of when blasts are required outside of the planned schedule. Throughout the blasting activity, if required, vibration sensors will be installed at strategic locations to monitor the impact of blasting and to ensure that the vibration levels are within the adopted criteria. The monitoring plan will be part of the Blasting Management Plan. Use blasting design with consideration of safety, blast geometry, free faces, burden, spacing, initiation pattern (delayed blasting) and angled holes. Use multi deck blasting technique is considered as efficient method creating lower vibration. Develop and implement suitable procedures for management of explosives, including security and storage arrangements. Must be produced in accordance with the requirements of the Biodiversity Management Plan (e.g. regarding avoidance of impacts to nesting birds and roosting bats, etc.). The Blasting Management Plan will set out the safe and secure storage of blasting equipment (including explosives) when not in use. 29 Construction Road A Construction Access Road Management Plan will be developed, which Preparation: PMU/ Supervising Plan approved as part of Access Management will include measures for the establishment, operation and timely contractor Engineer. the CEMP by relevant Plan reinstatement of the roads. Disruption to villagers along the construction Approval: Information – included parties. access roads must be minimized at all times. Supervising in reports to the The construction access roads shall be carefully chosen and delineated to Engineer, PMU Lenders. minimise impacts on landscape and soil erosion, and damage to bridges, river banks, verges, drain conduits and other structures along the route, and will be closely monitored to eliminate their unduly expansion during construction works. The top surface of access roads and work areas should be graded and compacted before works commences and maintained through the works to remove ruts and potholes. The access roads should be watered to reduce impact of dust caused by vehicles running on dry dusty surfaces. Speed limits should be identified by the contractor and strictly maintained to reduce noise and dust emissions and for road safety purposes. The requirements for environmental, social and safety controls on the access roads will be identified during the assessments of each route, but will implement the same types of management plan as set out in the EMP (for issues such as safety management, dust control, water control, etc.) for the main alignment.

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8.6 Operational Phase EMP

724. An EMP has been developed for the operational phase of the Project. This identifies the need for a number of sub-plans to manage specific issues or activities (Table 8.4).

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Table 8.4: Environmental Management Plan – operational phase

Ref Environmental Aspect Proposed Mitigation Measures Responsibility Target / / Concern Indicator Implementation Monitoring 1O Development of an The PMU shall prepare an over-arching operational phase Environmental EPC/PMU PMU OESMP and Operational Social & Management Plan (OESMP). The OESMP will Information – plans developed Environmental • Set out processes and responsibilities for implementation of the included in reports and implemented Management Plan requirements of permits, licences, lenders and regulations associated with to the Lenders. (OESMP) operation and maintenance of the Project after construction • include all of the sub-plans listed below Operational Stakeholder Engagement Plan (SEP) Operational Community Health and Safety Management Plan Operational Worker Health and Safety Management Plan Emergency Response Plans Operational Biodiversity Management Plan Operational Waste Management Plan Air Quality Management Plan Climate Resilience Management Plan The PMU will implement a OESMS in line with national and international EHSS Standards. This OESMP should be costed so that an annual budget can be established Community, Labour and Safety Management Plans

2O Operational Stakeholder • Update the Project SEP for the operational phase. EPC/PMU PMU Consultation Engagement Plan completed with • Implement the SEP and organise regular consultation activities with local Information – (SEP) the identified communities. included in reports to the Lenders stakeholders per • A Community Liaison Officer (CLO) shall be appointed to manage the SEP and consultations and implement the developed SEP with local communities. results of consultations • Organise consultation events for men, women and children (including presented to vulnerable groups) as and when required. PMU and ADB • Data to be collected on road safety from a gender perspective in the region and results communicated. • Update SEP on annual basis

3O Operational Community • Co-ordinate with police by the PMU to ensure regular patrolling as per EPC/PMU PMU Health and Safety other international roads. Management Plan

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Ref Environmental Aspect Proposed Mitigation Measures Responsibility Target / / Concern Indicator Implementation Monitoring • Consult with local households, community groups, police, and emergency Information – services as per the SEP. Investigate all community concerns related to included in reports dam operations, water supply, power generation operations. to the Lenders. • Inform community about any hazards and/or restrictions. • Maintain an accident log and review regularly to identify potential to reduce future accidents.

31O Operational Worker This will be developed in a format and with content consistent with international EPC/PMU PMU Health and Safety standards (e.g., World Bank Group EHSG, 2007). Information – Management Plan The Plan shall address health and safety hazards to workers associated with included in reports maintenance of roads, bridges, tunnels, etc. to ADB All workers (including sub-contractors) will receive a formal induction ahead of starting works, in a language(s) and format easily understood by the workforce. This will include information on health and safety measures, emergency response in case of accidents, fire, earthquakes, landslides, flash foods, disease etc, and minimisation of environmental and community impacts. The plan will include controls for: Health and Welfare • Provide reliable and sufficient supply of safe potable water at all times. • Provide portable toilet facilities with hand washing facilities for. PPE • Provide appropriate personnel protection equipment (PPE) (safety boots, helmets, gloves, protective clothes, etc.) appropriate to the task/activity. Plant and Equipment • Ensure the correct selection of all work equipment using on the project and that adequate information, instruction, training and supervision is given to all workers, • Regularly inspect, test and maintain all safety equipment. Immediately replace equipment that is not in working order, damaged and/or not fit to use. Mark all equipment to confirm it has been visually inspected and easily identifiable. • Ensure reversing signals are installed on all heavy maintenance vehicles. Work at Height / Fall Prevention • consider the application of a fall prevent hierarchy of control – avoid, prevent, minimise

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Ref Environmental Aspect Proposed Mitigation Measures Responsibility Target / / Concern Indicator Implementation Monitoring • Implement fall prevention and protection measures whenever a worker is exposed to the hazard of falling more than two meters, or other dangerous location. Fall prevention/protection measures may include installation and inspection of scaffolds by competent persons regular inspection of access equipment proper use of ladders and scaffolds by trained employees, use of fall prevention devices, including safety belt and lanyard travel limiting devices to prevent access to fall hazard, fall protection devices such as full body harnesses, etc. Regular inspection of fall prevention devices. Work in Confined Spaces • Develop a procedure for entry into confined spaces, including training of personnel, PPE requirements, rescue provisions, etc. • Prohibit entry into confined spaces, except by trained persons using the controls developed. Electrical Equipment and Electrical Works • Ensure that all electrical equipment is suitable for use in a harsh construction environment. • Regularly inspect electrical equipment and replace / repair if damage is identified. • Ensure that electrical works are only conducted by qualified and experienced personnel Hazardous Chemicals • Ensure that all hazardous chemicals are stored appropriately in suitable containers and labelled with the name and hazards of the contents. Site Illumination • Provide sufficient lighting at night within and in the vicinity of construction sites, but consider need for mitigation of impact on wildlife and community.

33O Operational Inspections must be conducted and managed by suitably qualified and EPC/PMU PMU, Information – No accidents. Maintenance Plan experienced engineers and in line with appropriate Samoan and international included in reports standards. to ADB. Sufficient resource must be provided for this programme. The maintenance plans will include inspections related to significant weather events as required by the Operational Climate Resilience Management Plan.

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Ref Environmental Aspect Proposed Mitigation Measures Responsibility Target / / Concern Indicator Implementation Monitoring All maintenance operations will be conducted in accordance with the Operational Worker Health and Safety Management Plan 36O Emergency Response Develop and implement emergency preparedness and response plans (ERP) EPC/PMU PMU Consultation Plans for the dam operational phase. These should include measures for prevention, Consultant as Information – completed with mitigation and response to emergency scenarios, at a minimum covering: required included in reports the identified • Accidents and injuries; to ADB stakeholders per the SEP and • Spills of hazardous substances; results of • Fire; consultations presented to • Natural disasters (earthquake, landslip, flood, extreme weather events, PMU and ADB etc.); The ERP should describe • Roles and responsibilities for prevention and response • Procedures for responding to different scenarios (fire, flood, traffic accident, etc.) • Resources required (personnel and equipment) and how these will be provided and maintained. This must consider delays to emergency response services, due to the remote location; • Competence and training requirements. Including response drills and exercises. The ERP must be regularly reviewed and updated – as a minimum annually and after any emergencies or accidents. Environmental Management Plans 38O Operational Biodiversity The Operational Biodiversity Management Plan will: EPC/PMU PMU E-flows and Management Plan • Ensure the implementation of the environmental flows as specified in PMU Consultant Information – environmental health of rivers Volume 2 – Annex D included in reports to ADB monitored • Align as necessary with the BMMP and BOP; Consultation • Prohibit poaching/plant and seed collection completed with the identified • Programme of education/awareness-raising of workforce to prevent stakeholders per hunting/poaching/collecting of rare seeds, etc the SEP and • Monitor the status of re-cultivated areas. (Note: monitoring of vegetation results of within the guarantee period (as defined by the contract) will form part of the consultations Construction Phase Landscape Management Plan, to ensure successful presented to establishment of replanting. PMU and ADB

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Ref Environmental Aspect Proposed Mitigation Measures Responsibility Target / / Concern Indicator Implementation Monitoring • During maintenance of the road and associated infrastructure implement mitigation measures set for construction stage. • Ensure the implementation of the Operational Waste Management Plan. • Remove all materials, equipment, tools from the area after completion of works. • Reinstate the sites disturbed during maintenance works, using species of local/regional provenance. 39O Operational Waste The Operational Waste Management Plan will: EPC/PMU PMU, Information – Reduced waste- Management Plan • Include wastes generated at operational facilities (dam, power station, included in reports based pollution. to ADB access roads, guard houses etc.), and during maintenance operations • describe waste streams and estimated amounts of each, • describe recycling / reuse methods for each material, • identify the waste destinations and transport modes, including what materials are being segregated on site for reuse or recycling, • specify responsibilities for managing and disposal of waste Waste from operational facilities • Apply the Waste Hierarchy • Install appropriate waste containers at all operational facilities. • Segregate hazardous, non-hazardous and reusable waste streams. • Manage and dispose hazardous waste according to the type and the class of hazard. • Provide bins and facilities at operational facilities for temporary storage of all waste streams. These facilities should be designed to prevent the escape of litter, liquids, odours or other contaminants / nuisance emissions. • Remove waste generating during maintenance activities according to the type and hazard category. 43O Operational Climate Develop and implement an Operational Climate Resilience Management Plan, EPC/PMU PMU Limiting damage Resilience Management which will include updates on changes in physical conditions and their Information – due to climate Plan projections, and which will specify requirements and processes (management included in reports change. framework) with respect to climate resilience. to ADB This shall include regular inspection across the project and especially after Maintenance Log. significant weather events such as flash floods (potentially damaging infrastructure in river valleys), intense rainfall events (potential mudslides), periods of long dry weather (due to dust). These inspections will be integrated with the Operational Maintenance Plan.

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Table 8.5: Monitoring Plan

Aspects/Parameters to be Monitored Location Means of Monitoring Frequency Implementation Responsibility Pre-construction/Site Preparation Phase Biodiversity Project site and haulage N/A For the duration of the contractor (Note: Pre-construction surveys as per requirements routes pre-construction phase included within the BMP) Review and audit of all water pipes along the alignment Project site and haulage Observation Prior to construction contractor routes Land acquisition and economic displacement audit N/a Observation Prior to construction Independent 3rd party Day time and nighttime vibration levels dB(A) Project site and haulage Instrumental Continuous and during contractor routes measurement blasting Effluent monitoring (camp sewage treatment) 50 m upstream and 250 m Analytical methods/ At least weekly, and in contractor (pH; Suspended Solids; BOD5; COD; Coliforms; Nitrate downstream the point of standards - ISO, USEPA accordance with (NO3); Phosphate (PO4); Oil and Grease) discharge from camp effluent or similar manufacturer’s plants Observation instructions Ground water level and quality Instrumental Seasonally contractor measurement Vegetation All work locations Observation Seasonally contractor Subcontractor audits N/a Observation Dependent on type and contractor duration of activity Labour audit All work locations Observation During the first month of PMU the construction phase Construction Phase Ambient air quality (Particulates PM10, PM2.5, CO, Project site and haulage Instrumental Monthly and response to contractor NOx, SO2) routes measurement complaints Day time and night-time noise levels dB(A) Project site and haulage Instrumental Monthly and in response contractor routes measurement to complaints Surface water quality Downstream of activities close Analytical methods/ Bi-weekly during project contractor (turbidity, pH, conductivity, total Oil and Grease, COD) to rivers or streams. standards - ISO, USEPA activities implemented or similar close to rivers or streams. Observation Biodiversity – as detailed within the BMP. As detailed within the BMP As detailed within the For the duration of the contractor BMP construction phase Gender Action Plan (GAP) As detailed within the GAP Observation and gender- For the duration of the PMU Gender sensitive indicators as construction phase Specialist / contractor / detailed within the GAP Specialist Consultant

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Aspects/Parameters to be Monitored Location Means of Monitoring Frequency Implementation Responsibility Workplace inspections and audits to monitor the All work locations Observation Monthly PMU / Engineer effectiveness of EHS control measures Waste company audits Site / waste disposal locations Observation Dependent on hazard contractor nature of waste and frequency of use Blasting contractor audit, to ensure all approvals and N/a Observation Prior to engagement of contractor authorisations are in place and good practices are supplier applied Regular inspection of scaffolds by competent persons All work locations with Observation After installation, weekly contractor scaffolds or following modification of inclement weather Regular inspection and testing of all lifting equipment, All work locations Observation Dependent on type of contractor including all straps, chains, shackles, etc equipment Inspection of dust control measures at concrete / asphalt All work locations Observation Weekly contractor plants Wind speed monitoring (for dust control purposes) All work locations Instrumental Daily and following contractor measurement significant increases in wind. Traffic and road conditions on construction site access Access roads Observation Dependent on traffic contractor roads and village access roads volumes Security patrols to prevent public access to hazardous All work locations Observation / cameras Throughout construction contractor areas Inspection of weather-related damage to construction All work location (specifically Observation Throughout construction contractor site, permanent and temporary assets exposed areas) and specifically following significant weather events such as flash floods, mudflows and heavy snowfall, or long periods of dry weather Ambient air quality (Particulates PM10, PM2.5, CO) Locations indicated by Instrumental Quarterly PMU complaints measurement In response to complaints Day time and night time noise and vibration levels dB(A) Locations indicated by Instrumental Quarterly and in other PMU complaints measurement sites in response to complaints Biodiversity –as detailed within the BMP As detailed within the BMP As detailed within the As detailed within the PMU BMP BMP Fish passage and health of rivers As detailed in Volume 2 – As detailed in Volume 2 – As detailed in Volume 2 – Specialist Annex C Annex C Annex C

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Aspects/Parameters to be Monitored Location Means of Monitoring Frequency Implementation Responsibility Environmental flows As detailed in Volume 2 – As detailed in Volume 2 – As detailed in Volume 2 – PMU or consultant as Annex D Annex D Annex D required Dam safety audits Dam Undertaken by technical Six-monthly Specialist consultant advisor Inspection of weather-related damage to assets Project site (specifically Observation Following significant PMU infrastructure in river valley) weather events such as flash floods, mudflows and heavy snowfall, and following long periods of dry weather (due to dust)

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8.7 Estimated Costs for Environmental and Social Protection Measures

725. Estimated costs for implementation of the environmental and social measures identified in the EIA are provided in Table 8.6.

Table 8.6: Costs associated with environmental protection elements of the Project

Element Description Cost Unit No. Cost (USD) Note 1 Subtotal Map mature and Specialist to field map mature trees USD5,000 Survey and report 1 USD5,000 USD58,000 specimen trees before design commences and avoid impact where possible Minimise Clearance Where possible minimise clearance Nil Included in detailed - No significant cost of Native Vegetation of native vegetation design Limit Site Access Barrier and staff cabin USD5,000 Provision of barrier and 1 USD5,000 shelter Critical Habitat Restore up to 240 ha of forest To be included in BOP Identification of suitable - - offset elsewhere in the Vaisigano River design costs location (implementation watershed costed under “operation” Construction Senior Environmental Specialist USD16,000 Person Months 3 USD48,000 USD451,000 Supervision (international) Consultant Note 2 Senior Occupational Health and USD18,000 4 USD72,000 Safety Specialist (International) Environmental Specialist (National) USD2,500 40 USD100,000 Occupational Health and Safety USD2,500 40 USD100,000 Specialist (National) Project Environmental spec. (national) USD2,500 Person Months 20 USD 50,000 Management Consultant Note 3 No Hunting contractor to enforce no hunting ban Nil (included in n/a - - (Education) within the project boundaries contractor management cost) Map Mature Trees Specialist to field map mature trees USD5,000 Survey USD5,000 before contractor commences work Minimise Clearance Consideration by the contractor Nil (included in n/a - No significant cost of Native Vegetation when identifying locations of camps, contractor management access roads, etc. cost) Replicate Native Where vegetation replanting is Cost of procurement of Provisional sum 1 USD30,000 over 30 Species carried out use native species native species years

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Element Description Cost Unit No. Cost (USD) Note 1 Subtotal Avoid Construction Avifauna specialist to advise Site work and report Advice to contractor No significant cost in Mao Breeding contractor to project Season Avoid Work close to Employment of Avifauna specialist USD5,000 Survey USD5,000 (for Mao nests to identify nesting sites survey) Environmental Noise (5 sites) Note 6 USD1,500 Set - each 6 months – 8 USD12,000 Note 5 Monitoring Note 7 (pre-construction and Air Quality (5 sites) USD3,000 6m & 12m) 8 USD24,000 Water Quality Note 8 (11 sites) USD615 8 USD5,000 Environmental Noise Note 6 (5 sites) USD1,500 Set - Annual for 2 years 2 USD3,000 USD631,000 Monitoring Note 4 post construction Air Quality Note 7 (5 sites) USD3,000 2 USD6,000 Water Quality (11 sites) USD615 2 USD1,230 Education in Education programme for local No specific cost, part of n/a n/a Conservation / community on the dangers of overall community invasive species introducing non-native species education / advice by EPC Install fish ladder Installation of a fish ladder on the USD50,000 for design 1 concrete / stone 1 USD50,000 and syphon face of the Samsoni Weir to facilitate and construction ladder installed on the structure above fish movements past the weir and downstream face of the Samsoni Weir also maintain an “environmental Samsoni Weir flow”. Syphon or similar structure TBD Critical Habitat Restore up to 240 ha of forest Considering two USD155,000- offset elsewhere in the Vaisigano River restoration offsets for 320,000/year watershed this Project totalling 120- 240 ha, restoration of native plants and control of invasive plants Translocation of Relocation of Mao Species to Based on costs of a One unit 1 USD250,000 Mao American Samoa translocation program for three bird of prey species to three sites Environmental Flow Maintain environmental flow in the n/a included within EPC n/a - - rivers from upstream to Apia Bay standard operating costs TOTAL USD1,140,000

Note 1) Project construction duration, including mobilisation and demobilisation (4 months) is 40 months (Almost 3.5 years)

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Note 2) Based on an International environmental specialist working in Construction Supervision Consultant (CSC) team for three person months over the project, an International Occupational Health and Safety Specialist for four person months over the project and National consultant as full time appointment over 40 months

Note 3) National Environmental; Consultant employed within the PMU as a Project Management Consultant half time over the project duration to audit performance, provide training and prepare 6 monthly monitoring report on behalf of EPC/PMU for ADB

Note 5) Environmental monitoring costs based on project monitoring experience

Note 6) Noise monitoring parameters: dB(A) 24 hrs

Note 7 Air Quality Monitoring parameters: СО, СО2, NO, NO2, SO2, Mechanical dust

Note 8) Costs of environmental protection included in contractor rates (i.e. no BoQ line item) not included (e.g. dust suppression, noise mitigation, waste management and operation of camps, etc.)

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9 Conclusions and Recommendations

9.1 Conclusions

726. This EIA has been prepared for the Alaoa Multi-purpose Dam Project, and has examined the design, construction and operation of a dam on the Vaisigano River catchment. The dam is considered necessary to control extreme storm events where there is rapid build-up and substantial water runoff down the river which has led to catastrophic physical damage to property downstream, loss of life, damage to infrastructure and flooding across Apia. Additional benefits include the ability to provide water storage for water supply and hydropower generation. 727. The EIA envisages that many of the potential adverse social and environmental impacts of the proposed final design option will be prevented and/or mitigated adequately and/or offset, and the positive impacts strengthened in the result of implementation of mitigation and enhancement measures identified in the EMP. The positive socio-economic and environmental effects of the project outweigh any environmental and social risks associated with its implementation. Implementation of the project will provide security to the population living downstream. Water retained behind the dam will provide security of water supply in periods of low rainfall and the new hydropower plant (constructed as part of the project, will generate electric power further reducing Samoa’s reliance on fossil fuels (diesel fuel) used to power conventional electric power generating equipment.

728. Construction and operation of the Alaoa dam will result in the permanent loss of habitat due to the inundation of 0.2 km2 (20 hectares) of riverbed, valley floor, and hillslope. For this reason, dedicated flora and flora surveys were carried out (terrestrial and aquatic habitat, avifauna and aquatic fauna and a critical habitat assessment). A dedicated archaeological assessment was also conducted which found no evidence of items of cultural heritage significance.

729. Potential environmental impacts were identified in relation to design, location, construction and operation of the dam and associated infrastructure and mitigation measures have been developed to remove or reduce any negative impacts to acceptable levels.

730. No permanent land acquisition of any kind (voluntary or involuntary) is expected under the current project scope and design. Nearly all proposed project works that fall under the scope of this EIA study are located within a single piece of government (public) land totalling 1,851 hectares that covers the middle and upper watershed of the Vaisigano River. Records show that the government acquired the land underlying the entire project area in 1921 in a manner that accords with the SPS and with applicable national laws.

9.1.1 Critical habitat issues

731. The development of the project will permanently inundate, and remove, a mosaic of natural and modified habitat, comprising secondary forest – including non-native species – and mixed subsistence farming. Downstream rivers have been degraded by cumulative impacts from existing weirs, but upstream rivers remain mostly natural habitat. A full critical habitat assessment identified this landscape to be possible or actual critical habitat for: one globally critically endangered and one endangered bird (Tooth-billed Pigeon and Mao); two endangered lizards (Olive Small-scaled Skink and Samoa Skink); three least concern, one data deficient and one not evaluated fish species (Fat-snout Goby, Stenogobius genivittatus, Green Riffle Goby, Stiphodon hydroreibatus, and Schismatogobius tuimanua); an endangered snail (Thaumatodon hystricelloides); one critically endangered and one Endangered palm (Drymophloeus samoensis and Clinostigma samoense); and the Apia Catchments Key Biodiversity Area.

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732. Without mitigation, the Project could have high impacts on some of this Critical Habitat-qualifying biodiversity, owing to forest loss and introduction, spread of invasive alien species, and/or prevention of migration of fish above the dam.

733. Recommendations. The Natural and Critical Habitat Assessment identified mitigation and management measures necessary to reduce residual impacts on critical habitat-qualifying biodiversity to levels in line with the SPS. Key mitigation measures are:

• A strict code of conduct forbidding hunting/trapping, and purchase of wildlife, with heavy penalties. Training personnel on this code of conduct, and its justification; • Install staffed access control on new roads, allowing access to no-one except operational staff, or government officials; • Engage and educate the local community, including providing incentives to conserve priority biodiversity - such as employment in restoration, invasive species control and monitoring; and • Taking care to avoid introduction of new invasive species to, and spread of existing invasive species within, the Project area. • Prior to finalization of project designs and any clearance, identify, clearly mark and map all mature native trees, to facilitate avoidance and minimization; • Minimize clearance of native vegetation at the Project site and around associated roads and other infrastructure; using already cleared or modified areas for construction wherever possible. Prioritize avoidance of Ficus and Dysoxylum trees (which may provide seasonal food sources for Tooth-billed Pigeon), and attempt to relocate any of these which cannot be avoided; • Replant native vegetation (including Dysoxylum species) in any temporarily disturbed areas; • Regularly maintain and inspect/certificate all vehicles, equipment and machinery to ensure that noise levels conform to national standards; • Avoid construction during the most sensitive Mao breeding period (June-August inclusive); • Avoid construction within 150 m of an occupied Tooth-billed Pigeon or Mao nests; • Educate local people on the dangers of deliberate introductions of invasive species.

734. After these mitigation measures, the Project is predicted to reach no net loss for most Critical Habitat-qualifying biodiversity. However, some residual impacts on this priority biodiversity are expected to remain measurable by the Project operations phase, particularly direct loss of terrestrial and aquatic habitat, and degradation of upstream habitats by prevention of aquatic species’ migration past the dam, but also downstream degradation of aquatic habitat and fragmentation of terrestrial habitat owing to the Project roads and reservoir

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9.1.2 Environmental Flow issues

735. The Vaisigano River provides habitat for six migratory fish and seven migratory crustacean species, including reaches within the proposed inundation zone and in the reaches upstream of the inundation zone in the east and middle-east branches. All of the migratory species present have to move between freshwater and marine habitats to complete their life cycle. The reaches assessed as modified and natural habitat have been assessed as providing critical habitat for five species of migratory fish

736. Regulation has significantly reduced the flow regime in the five kilometres of the east branch downstream the offtake for the Fale ole Fee Power Scheme; the 1.3 kilometre reach of the middle branch downstream from the offtake for the Alaoa Scheme; and, the 4.2 kilometre reach of the main branch downstream from Samasoni Weir to the tailrace for Samasoni Power Scheme. These reaches experience zero flow for extended periods each year, provide no aquatic habitat and reduce the pathways for migratory species to move up and downstream.

737. The objectives of the environmental flow mitigation is to restore flow lost to the current hydro-power schemes and to offset the impacts of the new project by improving migration opportunities into the lower (main branch), mid (main, middle and west branches) and upper reaches (middle and west branches) of the catchment. If the environmental flow is implemented, operation of the new dam is predicted to result in no net loss of biodiversity in the catchment.

738. Recommendations. It is proposed to release a permanent baseflow from Samasoni Weir and from the offtake weir on the middle branch. A monthly fresh rule is also proposed from these locations to increase the frequency and duration that higher flows are delivered downstream.

739. The release of a permanent baseflow from these reaches will provide the following environmental benefits:

• Restore permanent aquatic habitat to 4.2 kilometres of the main channel downstream from the Samasoni Weir and the final 1.3 kilometre reach of the middle branch before it joins the west branch. • Allow populations of goby, eel, shrimp, prawn and macroinvertebrate to establish in these reaches • Restore connectivity and migratory pathways from the sea to the upper reaches of the catchment. Specifically, a permanent baseflow will increase opportunities for: o the downstream migration of larval gobies, prawns and shrimps to reach the sea o adult eels to migrate downstream to the sea to breed o upstream migration of juvenile gobies, eels, prawns and shrimps from the lower reaches and the sea • Provide social benefits for increased access to permanent flowing reaches for washing and recreational fishing

9.1.3 Concluding remarks

740. Overall the proposed Project is unlikely to cause significant adverse environmental or social safeguards impact. This is due to the following findings:

• The land that the project will be located in, including the impounded area was acquired by Government in 1921. Those affected by that land acquisition have been adequately compensated and concerns raised by a small number of claimants have been shown to

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be without merit. No permanent land acquisition of any kind (voluntary or involuntary) is expected under the current project scope and design. • Five project specific reports have been produced on ecological issues: terrestrial flora and fauna; avifauna; aquatic ecology environmental flow and critical habitat and concluded that with identified mitigation and offsetting, ecological impact can be adequately compensated • A dedicated record and site survey concluded that there are no sites of cultural or heritage significance within the area of influence of the project. • Typical construction impacts due to the operation of construction plant, processing areas, etc., and operation impacts of dam infrastructure can be readily mitigated by good site practise giving rise to nil, negligible or at worst, minor temporary environmental impacts.

741. An EMP has been prepared for the project. The EMPs are included as part of this EIA and include (i) mitigation measures for potential environmental impacts during implementation, (ii) environmental monitoring program, and (iii) the responsible entities for mitigation, monitoring, and reporting.

742. Mitigation will be assured by a program of environmental monitoring to be conducted during the construction stages. The environmental monitoring program will ensure that all mitigation measures proposed in the EMPs are implemented and will determine whether the environment is protected as intended. Any requirements for remedial action will be reported to the ADB.

743. Project stakeholders were consulted during preparation of the EIA and invited to express any environmental and social concerns they had regarding the project. No significant environmental and social concerns were raised, and all stakeholders consulted strongly support the project and are looking forward to the security provided by the Alaoa dam. The EIA will be made available at public locations and will be disclosed to a wider audience via the ADB website. The consultation process will be continued during project implementation to ensure that stakeholders are fully engaged in the project and have the opportunity to participate in its development and implementation

744. Environmental and social benefits of the investment components and long-term project objectives far outweigh the minor and temporary inconveniences that will arise during project implementation. Provided the EMPs are properly implemented there will be no unacceptable impacts arising from the project. This EIA including EMP are considered sufficient to meet the environmental assessment requirements of ADB and Government of Samoa.

9.2 Requirements and Recommendations

745. The following are the requirements and recommendations of the EIA:

• Design of fish ladder and structure upstream of the Samasoni weir and downstream of the confluence of the western branch, to encourage fishes up the western (and to be restored branch – which will be better quality habitat and the fish can go farther upstream) rather than up the middle branch;

• The powerhouse is relocated to the toe/foot of the dam to ensure there is no de-watered stretch;

• The BMMP and BOP, to be prepared, outlines additional biodiversity protection, mitigation and offsetting measures to be implemented by the government. The government will commit to the institutional and implementation arrangements set out in the BMMP and BOP;

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• The EIA will be finalized pending comments and submissions during the public disclosure period, detailed design and development of the BMMP and BOP. The finalized EIA will be formatted as a CEAR and submitted with the application for development consent for the Project;

• The DB contractor will engage a suitably qualified specialist to assist in development of the CEMP and sub-plans, and additional expertise as required for the BMP, FCP and other plans as required;

• EPC implement the environmental flows as set out in Volume 2 – Annex D;

• The PMU/CSC will recruit a suitable avifauna specialist to undertake surveys prior to any clearance and construction activities commencing; and

• Irrespective of financing arrangements for components of the project, the EIA and environmental safeguards and management measures will be implemented.

9.3 Provisions for the Grant Agreement

746. The following sets out the recommended provisions to be included in the grant/financing and/or Project agreement.

------

Notwithstanding any other provision of this Grant Agreement, no withdrawals shall be made from the Grant Account until: … (x) the Recipient has cleared the final EIA and Biodiversity Management and Monitoring Plan and Biodiversity Offsetting Plan, including obtaining development consent for the Project, and obtained ADB’s clearance of the EIA and Biodiversity Management and Monitoring Plan and Biodiversity Offsetting Plan. …

SCHEDULE 5 Execution of Project; Financial Matters … Safeguards – Related Provisions in Bidding Documents and Works Contracts

The Recipient shall ensure that the Implementation Agreement, and cause the EPC to ensure that the DB Contract, contain provisions that require the EPC and DB Contractor to:

(a) comply with the measures relevant to the contractor set forth in the EIA, the EMP, the CEMP, Biodiversity Management and Monitoring Plan and Biodiversity Offsetting Plan, the RP (to the extent they concern impacts on affected people during construction), and any corrective or preventative actions set forth in monitoring reports including Safeguards Monitoring Reports;

(b) make available a budget and designate staff for all such environmental and social measures;

(c) provide the Borrower with a written notice of any unanticipated environmental, resettlement or indigenous peoples risks or impacts that arise during construction, implementation or operation of the Project that were not considered in the EIA, the EMP, CEMP, Biodiversity Management and Monitoring Plan and Biodiversity Offsetting Plan, and the RP;

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(d) adequately record the condition of roads, agricultural land and other infrastructure prior to starting to transport materials and construction; and

(e) reinstate pathways, other local infrastructure, and agricultural land to at least their pre-project condition upon the completion of construction.

Condition of Contract Award x. The Recipient shall not award the DB contract until: (a) the Recipient has ensured or caused the EPC to implement the environmental flows for the existing hydro schemes within the Vaisigano catchment as specified in the EIA; (b) the Recipient has ensured or caused the EPC to install telemetry gauges at locations to be determined within the Vaisigano catchment and record data to be monitored by MNRE-WRD and reported in the progress reports and semi-annual monitoring reports to be prepared for the Project by the EPC; (c) the EPC PMU is staffed and resourced as per the requirements and arrangements set out in the PAM.

Environment x. The Recipient shall ensure or cause the EPC to ensure that the preparation, design, construction, implementation, operation and decommissioning of the Project and all Project facilities comply with (i) all applicable laws and regulations of the Borrower relating to environment, health and safety; (ii) the Environmental Safeguards; and (iii) all measures and requirements set forth in the EIA, the EMP, Biodiversity Management and Monitoring Plan and Biodiversity Offsetting Plan, the CEMP, and any corrective or preventative actions set forth in monitoring reports including Safeguards Monitoring Reports. …

Safeguards Monitoring and Reporting z. The Recipient shall do the following or cause EPC to do the following:

(a) submit separate quarterly Safeguards Monitoring Reports on environmental safeguards and social safeguards to ADB and disclose relevant information from such reports to affected persons promptly upon submission;

(b) if any unanticipated environmental and/or social risks and impacts arise during construction, implementation or operation of the Project that were not considered in the EIA, the EMP, CEMP, Biodiversity Management and Monitoring Plan and Biodiversity Offsetting Plan, the RP, promptly inform ADB of the occurrence of such risks or impacts, with detailed description of the event and proposed corrective action plan; and

(c) report any actual or potential breach of compliance with the measures and requirements set forth in the EMP, CEMP, Biodiversity Management and Monitoring Plan and Biodiversity Offsetting Plan, or the RP promptly after becoming aware of the breach.

Condition of Approval to Commence Physical Works The Recipient shall ensure and cause the EPC to ensure that, prior to the no objection for commencement of any physical works (including clearing and grubbing), the DB Contractor:

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(a) has prepared, and submitted for approval, the CEMP and all of the plans specified in the EIA, satisfactory to ADB, to effectuate the mitigation measures as set out in the EIA; (b) has prepared, and submitted for approval, a time-bound action plan, satisfactory to ADB. The timebound action plan will be required to identify all of the mitigation measures, how they will be implemented, cooperating agencies to ensure they are implemented, costs and budget lines etc

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Appendices and Annexes

In this document appendices are defined as information referenced from the main text but where information is considered too bulky and would adversely affects the flow of the text. An Annex is a stand-alone document that is summarised in the main text. The 11 annexes are compiled as EIA Volume 2 as follows:

Annex A – Noise Monitoring Report

Annex B – Terrestrial Biodiversity and Habitat Assessment

Annex C – Aquatic Biodiversity and Habitat Assessment

Annex D – Environmental Flow Assessment

Annex E – Geomorphic Impact Assessment

Annex F – Archaeological Survey

Annex G - Land Acquisition / Resettlement Plan

Annex H – Stakeholders Consultation and Participation Report

Annex I – Climate Change

Annex J - Assessment of Ecological Effects: Birds and Bats

Annex K – Critical Habitat Assessment

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Appendix 1 – Environmental documents reviewed in the preparation of this EIA

No Relevance By For Revision Date 1 Engineering First Draft Technical Feasibility Study Report Entura 08-May-18 2 Other GOOD PRACTICE NOTE Environmental, Health, and Safety Approaches for Hydropower Projects IFC Mar-18 3 Other GOOD PRACTICE HANDBOOK Environmental Flows for Hydropower Projects Feb-18 4 Other Afulio Dam Monitoring Assessment Report - Monitoring for the conditions leading to hydrogen sulphide gas production Watercheck Mar-08 5 Other Preparing The Afulilo Environmental Enhancement Project ADB TA: 7121 SAM SMEC ADB / EPC Draft2 Apr-11 6 Engineering FEASIBILITY STUDY OF VAIPU TO AFULILO DAM POWER PUMP STATION Egis Bceom International EPC PMU Dec-08 7 Engineering Appraisal of Afulilo hydroelectric project EPC ADB Nov-86 8 Samoa EIA EIA Report on the Augmentation of the Afulilo hydroelectric project SPREP Gov of Samoa Nov-97 9 Samoa EIA IEE Samoa: Fuluasou HPP James Atherton and Associates ADB Apr-13 10 Samoa EIA IEE Samoa: Tiapapata HPP James Atherton and Associates ADB Aug-13 11 Samoa EIA IEE Samoa: Alaoa HPP James Atherton and Associates ADB 2013 12 Samoa ConservationSamoa HHP Species List James Atherton and Associates Jul-05 13 Samoa EIA IEE for new SHPP schemes STR + P&P ADB Oct-13 14 Samoa ConservationRidge to Reef Programme - Samoa GEF 15 Samoa ConservationVAISIGANO WATERSHED MANAGEMENT PLAN 2013 MNRE Draft Mar-13 16 Samoa EIA Samoa: IEE Renewable Energy Development and Power Sector Rehabilitation Project: Fuluasou and Tiapapata Small Hydropower Projects EPC ADB final draft 27-Apr-15 17 Other Tiapapata Critical Habitat Assessment EPC ADB comments and responses 18 Other EMP Plans and Framework JW briefing 19 Samoa EIA Draft Initial Environmental Examination (IEE) report for Proposed Works at Tiapapata and Fuluasou MNRE EPC PMU 30-Apr-15 20 Other EIA Managing Labour Influx ADB ESSAT briefing note01-Dec-16 21 Other ConservationSOL Tina River Hydropower Development -assessment of effects on aquatic ecology and possible mitigation measures Jowett Consulting Ltd Ministry of Mines, EnergyMar-16 and Rural Electrification 22 Engineering Draft Mid-Term Technical Feasibility Study Report Entura ADB draft 08-Jun-18 Other MEMORANDUM OF UNDESTANDING TA 9242-REG: MIDTERM REVIEW MISSION FOR ALOA MULTI-PURPOSE DAM PROJECT ADB

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Appendix 2 – Project specific studies prepared as part of EIA process

Aspect Title Description Date Environmental Ambient noise monitoring at the Noise monitoring October 2018 Baseline site and on access roads Terrestrial Biodiversity and Terrestrial ecology survey and Ecology March 2019 Habitat Assessment assessment of impact Aquatic Biodiversity and Habitat Aquatic ecology survey and Ecology Feb 2019 Assessment assessment of impact Assessment of existing situation and options for maintaining an Environmental Flow Ecology acceptable minimum flow in the Sept 2019 Assessment Vaisigano river during the operation phase of the AMPDP Origin and evolution of topographic Ecology Geomorphic Impact Assessment June 2019 features in the project area Reporting on archaeological Surveys March Cultural heritage Archaeology Survey desktop and field survey of the 2019 project area Issues associated with land Land Acquisition / Resettlement Social Safeguards occupation and ownership and Oct 2019 Plan (draft) compensation issues Stakeholders Consultation and Details of the consultations Social Safeguards May 2019 Participation Report undertaken as part of the project Impacts of climate change on the Engineering Climate Change project. Extracted from Oct 2018 Engineering Feasibility Report Additional data collection (including automated recorders Assessment of Ecological Ecology deployed at project site) and Dec 2019 Effects: Birds and Bats assessment of impacts on bird and bat species Assessment of impacts on habitats Natural and Critical Habitat Ecology affected by the Alaoa Multi- Dec 2019 Assessment purpose Dam project

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Appendix 3 –Plant list for Project Influence Area

Scientific Name Samoa/Common name Use Dominance Adenanthera pavonina lopa Alien Invasive 3% Alibizia falcatera tamaligi paepae Alien Invasive 26% Biscofia javanica o'a/mulberry tree Ornamental - breadfruit Artocarpus spp Food crop - Cananga odorata mosooi Ornamental 4% Castilla elastica pulu mamoe/ rubber tree Invasive 20% Cocos nucifera Niu/coconut Food crop - Cordyline terminalis Ti Native shrub - Cestrum nocturnum teine o le po Invasive - Clidemia hitra Lapiti/ Kusters curse Alien invasive - Collocasia spp taro Food crop - Cyathea lunulata Olioli/tree fern Native 1% Erythrina variegata gatae Alien legume tree - Ficus scabra mati Native - Flueggea flexuosa poumuli Timber tree - Funtumia elastica pulu vao Alien invasive 13% hibiscus tiliaceus fau Secondary forest tree - Kleinhovia hospita fu'afu'a Secondary forest tree 3% Laportea photiniphylla Salato Secondary forest tree 1% Macropiper puberulum ava Native crop - manihot esculenta manioka Food crop - Morinda citrifolia nonu ornamental - Musa spp banana Food crop - Neonauclea fosteri Afa Native forest tree - Passiflora luarifolia pasio vao Invasive - Planconella garberi Gasu native forest tree 2% Plqnconella torricellensis mamalava Native forest tree 2% Pometia pinata Tava Native forest tree 17% Rhus taitensis tavai Secondary forest tree 6% Schizostachyum glaucifolium Bamboo / ofe Forest tree - Sida parviflora mautofu Invasive weed - Spathodea campanulata faapasi Alien invasive - Theobroma cacao cocoa Food crop - Terminalia glabrata Talie Native tree - Trema cannabina magele Native shrub -

Source: Terrestrial Biodiversity and Habitat Assessment (Volume 2 – Annex B)

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Appendix 4 – Data utilized and calculations undertaken in GHG emissions estimate for Alaoa multipurpose dam

No. Data Value Units Data Source

Emissions from new reservoir 1. Area at FSL 22 hectares Technical feasibility report 2. Inundation land-use coverage 90% secondary and EIA plantation tropical rainforest 10% waterbody 3. Above ground biomass 69 tonnes dry wt/ha IPCC 2019 (Asian mixed tropical rainforest) 4. Proportion of above ground biomass as 0.47 IPCC 2006 C (Tropical and subtropical forest) 5. Above ground carbon 32.4 tonnes C/ha 2, 3 and 4 above 6. Litter carbon 5.9 tonnes C/ha IPCC 2019 (Tropical moist forest) 7. Soil carbon 77 tonnes C/ha IPCC 2019 (Volcanic soils – tropical wet) 8. Total carbon 2466 tonnes C 1, 2, 5, 6 and 7 above 9. Proportion Carbon available for 50% Assumption from Liden (2013) decomposition 10. Total carbon available for 1233 tonnes C 8 and 9 above decomposition

11. Proportion C emitted as CO2 93% Liden (2013)

12. Proportion C emitted as CH4 7% Liden (2013)

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No. Data Value Units Data Source

13. Total CO2 equivalents emitted 7080 tonnes CO2 equiv 10, 11 and 12 above

Incorporates empirical conversion of C to quantities of CH4 and CO2

Utilses CH4 conversion factor to CO2 equiv. of 25

14. Annual average reservoir CO2 70.80 tonnes CO2 equiv/y From 13 above. Assumes 100 year reservoir life-cycle equivalent emissions Current sinks 15. Above ground biomass growth 2.7 tonnes dry wt./y IPCC (2019) (Secondary tropical rain forest) 16. Above ground biomass C 1.27 tonnes C/y 15 and 4 above.

17. Annual removal CO2 equivalent in 4.6 tonnes CO2 equiv/y Empirical conversion of 16 above inundation area Current emissions

2 18. Emission from natural waters 463 tonnes CO2/km /y Standard emission estimate from natural waters. Barros et al (2011) 19. Area of natural waters to be inundated 0.024 km2 Assumes 10m average width of current rivers (2.4 km length)

20. Annual emission from waterways in 11.1 tonnes CO2 equiv/y 18 and 19 above inundation area Net emissions from new reservoir

21. Net emissions from Alaoa Reservoir 64.4 tonnes CO2 equiv/y 14, 17 and 20 above Low GHG Compatability Test 22. Annual generation 2.12 GWh Technical Feasibility report

22. Reservoir Emissions Intensity 30.35 g CO2 equiv/ kWh 21 and 22 above

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Appendix 5 – Construction Noise Calculations

Sound

Number Power

correction correction correction correction used Level correction Allowable diff distance attenuation dB(A) 1) Quarry / Borrow Area Rock Drill (Crawler Mounted) 1/3 128 128 3 131 0.5 132 0 132 132 55 77 >700m Rock Drill (Crawler Mounted) 2/3 128 128 Breaker, excavator mounted (pneumatic/ hydraulic) 1 122 0 diff 122 Wheeled Loader 1 112 9 diff 112 Trucks 1 112 20 diff 112 Excavators 1 112 20 diff

2 & 3) Site preparation / Earthworks Preparing base Scraper 1 119 119 119 55 64 318 to 351m

Rolling base Roller, vibratory 1 108 108 108 55 53 108 to 118m

Dump truck 1 117 117 2 119 1 120 120 55 65 352 to 387m Laying base Bulldozer 1 115 115 Grader 1 113 2 diff 113 6 dif

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4) Concrete Construction Poker, vibratory, hand-held 1/3 113 113 3 116 2 118 1 119 1 120 0.5 121 120 55 66 388 to 427m Poker, vibratory, hand-held 2/3 113 113 Poker, vibratory, hand-held 3/3 113 0 diff 113 In-situ Concrete Crane, mobile/barge mounted (diesel) 1 112 work 3 dif 113 Concrete lorry mixer 1 109 5 diff 112 Concrete pump, stationary/lorry mounted 1 109 7 dif 109 Generator, standard 1 108 11 dif

Lifting elements Crane, mobile/barge mounted (diesel) 1 112 112 112 55 57 160 to 175m

5) Travelling on Access Road Construction Lorry 1 112 112 112 55 57 160m

6) Manufacturing Area Lorry 1 112 112 3 115 1 116 0.5 117 0.5 117 0 117 55 62 261 to 268m Excavator/loader, wheeled/tracked 1 112 112 Batching plant (asphalt / concrete) 1 108 0 diff 108 Batching plant (asphalt / concrete) 1 108 7 diff 108 Generator, standard 1 108 8 dif 108 Generator, silenced, 75 dB(A) at 7 m 1 100 8.5 dif 100 Power pack for hand-held items of PME 3 100 17 dif Bar bender and cutter (electric) 1 90

Alaoa Multi-Purpose Dam Project - Environmental Impact Assessment Revision No: 3.1 E307132 10-Feb-20