Sri Lanka: DRY ZONE URBAN WATER and SANITATION PROJECT - for Vavuniya Per Aru Reservoir

Environment Impact Assessment Report

Project Number: 37381-013 November 2012

Sri Lanka: DRY ZONE URBAN WATER AND SANITATION PROJECT - for Vavuniya Per Aru Reservoir

Prepared by Project Management Unit for

Dry Zone Urban Water and Sanitation Project,

For Water Supply and Drainage Board Ministry of Water Supply and Drainage, Sri Lanka.

This report has been submitted to ADB by the Ministry of Water Supply and Drainage and is made publicly available in accordance with ADB’s public communications policy (20011). It does not necessarily reflect the views of ADB.

THE DEMOCRATIC SOCIALIST REPUBLIC OF SRI LANKA

MINISTRY OF WATER SUPPLY AND DRAINAGE

NATIONAL WATER SUPPLY AND DRAINAGE BOARD

ENVIRONMENTAL IMPACT ASSESSMENT ON THE PROPOSED SURFACE WATER EXTRACTION FROM A RESERVOIR ACROSS PER ARU VAVUNIYA DISTRICT

November 2012

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

ABBREVIATIONS

ADB = Asian Development Bank APs = Affected People BCR = Benefit Cost Ratio BOD = Biological Oxygen Demand BOP = Blocking out Plans CBO = Community Based Organization COD = Chemical Oxygen Demand DCSMS = Design, Construction, Supervision and Management Support DFC = Department of Forest Conservation DFO = Divisional Forest Officer DOA = Department of Agriculture DS = Divisional Secretary DWC = Department of Wildlife Conservation DZ = Dry Zone EC = Electrical Conductivity EMU = Environmental Management Unit FD = Forest Department FOs = Farmer Organizations FR = Forest Reserve FSL = Full Supply Level GA = Government Agent GDP = Gross Domestic Product GIS = Geographical Information Systems GN = Grama Niladhari – A village Headman GPS = Global Positioning System GSMB = Geological Survey and Mines Bureau ha. = Hectare HBPL = Household Population below poverty line IEE = Initial Environmental Examination IRR = Internal Rate of Return IUCN = International Union for Conservation of Nature JICA = Japan International Cooperation Agency LAA = Land Acquisition Act LARC = Land Acquisition & Resettlement Committees

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

LGA = Local Government Authority LHG = Low Humic Gley Soils MASL = Mahaweli Authority of Sri Lanka MCM = Millions of Cubic Meters MSL = Mean Sea Level MSW = Municipal Solid Waste NCP = North Central Province NEA = National Environmental Act NGO = Non Governmental Organization NIRP = National Involuntary Resettlement Policy NP = National Park NPV = Net Present Value NWSDB = National Water Supply and Drainage Board O&M = Operations and Maintenance OFC = Other Field Crops PD = Project Director RBE = Reddish Brown Earths RE = Resident Engineer RIP = Resettlement Implementation Plan RIS = Reservoir Induced Seismicity SIA = Social Impact Assessment SLS = Sri Lanka Standards SPM = Small Particulate Matter SPM = Suspended Particulate Matter SWM = Solid Waste Management TDS = Dissolved Solids TOR = Terms of Reference UNDP = United Nations Development Programme WRB = Water Resources Board WTP = Water Treatment Plant

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir CONTENTS

EXECUTIVE SUMMARY EXECUTIVE SUMMARY ...... I

A. BACKGROUND ...... I

B. PROJECT CONFIGURATION ...... I

C. PROJECT IMPACT AREA AND THE STUDY AREA ...... I

D. PROJECT JUSTIFICATION ...... II

E. PHYSICAL AND BIOLOGICAL ENVIRONMENT ...... II

F. SOCIO ECONOMIC ENVIRONMENT ...... III

G. ARCHAEOLOGICAL AND CULTURAL CONSIDERATIONS ...... IV

H. KEY ENVIRONMENTAL IMPACTS AND MITIGATORY MEASURES ...... IV

I. ENVIRONMENTAL MANAGEMENT AND MONITORING PLAN ...... VI

J. CONCLUSION AND RECOMMENDATION...... VI

I. INTRODUCTION ...... 1

A. BACKGROUND OF THE PROJECT ...... 1

B. OBJECTIVES AND JUSTIFICATION OF THE PROJECT ...... 1

C. OBJECTIVE OF THE EIA REPORT ...... 1

D. METHODOLOGIES AND TECHNOLOGIES ADOPTED FOR PREPARATION OF THE EIA REPORT ...... 2 1. Survey of existing literature 2 2. Field investigations 3 3. Geological investigations 4 4. Soil study 4 5. Study on surface water quality 4 6. Study on ground water quality 4 7. Study on air quality 4 8. Study on noise and vibration 5 9. Observations on archaeology 5 10. Spatial data 5 11. Non‐spatial data 5 E. GOVERNMENT POLICY REGARDING THE PROJECT ...... 5

F. CONFORMITY WITH OTHER DEVELOPMENT PLANS IN THE AREA ...... 7

II. DESCRIPTION OF THE PROPOSED PROJECT AND REASONABLE ALTERNATIVES ...... 9

A. DESCRIPTION OF THE PROJECT ...... 9 1. Name and location of the project area 9 2. Key feature of the proposed project 9 3. Temporary constructions and construction material 15 4. Methodology of construction of Per Aru reservoir 15 5. Methodology of operation 19 6. Workforce requirements 19 7. Phased implementation plan of the project 19 8. Total project cost, investment and funding sources 19 B. EVALUATION OF ALTERNATIVES ...... 21

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir 1. No action alternative 21 2. Site alternatives 21 3. Design alternatives 22 III. DESCRIPTION OF THE EXISTING ENVIRONMENT ...... 25

A. TOPOGRAPHY AND THE STUDY AREA ...... 25

B. PHYSICAL ENVIRONMENT ...... 31 1. Geology 31 2. Geotechnical condition 32 3. Leakage conditions 35 4. Agro‐ecological regions 35 5. Land suitability 37 6. Climate of the low country dry zone 37 7. Mineral resources 38 8. Rainfall 41 9. Temperature 42 10. Evaporation 42 11. Hydrology 43 12. Groundwater 51 13. Land use 58 14. Air quality and noise 63 C. BIOLOGICAL ENVIRONMENT ...... 66 1. Proximity to wildlife reserves and forest reserves 66 2. Ecological status of the project area 71 3. Per Aru upper catchment area 73 4. Inundated area and downstream of the Dam 79 5. Species habitat of potential resettlement land for inundated agricultural lands 97 D. HUMAN SETTLEMENT AND LAND USE ...... 101 1. Settlement of the affected population 101 2. Population characteristics of the affected population 101 3. Income generation sources and patterns 104 4. Present water supply and water uses 108 5. Culture and historical aspiration of the affected people 110 6. Existing infrastructure facilities. 110 7. Reported environmental incidents 110 IV. ANTICIPATED ENVIRONMENTAL IMPACTS ...... 111

A. IMPACTS ON SOIL AND TOPOGRAPHY ...... 111

B. IMPACTS ON HYDROLOGY AND WATER QUALITY ...... 111 1. Changes in surface water flow 111 2. Changes of groundwater table 111 3. Favorable aspects of impoundment 112 4. Water pollution due to machinery and site activities 112 5. Impacts on surface water quality (operation phase) 112 C. IMPACTS OF AIR POLLUTION ...... 112

D. IMPACTS OF NOISE AND VIBRATION ...... 113

E. ECOLOGICAL IMPACTS ...... 115 1. Impacts onterrestrial fauna and flora due to habitat losses 115 2. Impacts on aquatic fauna and flora due to the project. 116 3. Impacts on nearby forest reserves (if any) 117 4. Impacts on nearby wildlife reserves and wildlife migration 117

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

5. Impacts on wetlands due to changes in water balance 117 6. Risk of invasive species 117 7. Impact on threatened species and biological diversity 118 F. SOCIOLOGICAL / CULTURAL IMPACTS ...... 118 1. Impacts on existing water usage/ extraction/irrigation schemes 118 2. Relocation of affected people 118 3. Change/disruption of life style 119 4. Change in land use pattern 119 5. Impact on quality of life 119 6. Employment generation during construction and operation 119 7. Impacts on historical, cultural and religious significance 120 V. ENVIRONMENT MANAGEMENT AND MITIGATION ...... 121

A. MITIGATION OF PHYSICAL IMPACTS ...... 121 1. Land management 121 B. SUSTAINABILITY ON CRITICALLY ENDANGERED FAUNA SPECIES ...... 134 1. Mitigating the impacts on aquatic fauna and flora 142 2. Mitigating measures for new agricultural lands 142 3. Mitigation of air pollution impacts in construction phase 143 4. Mitigation of air pollution impacts in operation phase 144 5. Mitigation of noise and vibration impacts during construction 144 6. Mitigation of noise and vibration in the operation 144 7. Grievance redress mechanism 145 VI. ENVIRONMENTAL MANAGEMENT PLAN AND COST BENEFIT ANALYSIS ...... 149

A. ENVIRONMENTAL MANAGEMENT ACTIVITIES ...... 149 1. Extended cost‐ benefit analysis 161 VII. ENVIRONMENTAL MONITORING PROGRAM ...... 167

A. PARAMETERS TO BE MONITORED ...... 167 1. Engineering and physical aspects; 167 2. Water quality 168 3. Ecological parameters 168 4. Public Health 168 5. Institutional arrangements 168 VIII. CONCLUSIONS AND RECOMMENDATIONS ...... 177

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

LIST OF TABLES

Table 1 : Design details of the proposed water treatment plant ...... 14 Table 2 : Quantities of excavation requiring disposal ...... 17 Table 3 : Construction schedule for Per Aru reservoir...... 20 Table 4 : The design alternatives with affecting lands ...... 22 Table 5 : The options of dam and the land use ...... 23 Table 6 : Summary of VES observations – Vavuniya ...... 32 Table 7 : The characteristics of sub regions ...... 35 Table 8 : Monthly rainfall at different probability levels ...... 42 Table 9 : Monthly average stream flow from Dec. 2008 to Dec. 2010 (m3 /sec) ...... 44 Table 10 : Elevation ‐ discharge relationship...... 45 Table 11 : Monthly In generated In flow (MCM) at dam site ...... 46 Table 12 : Probability inflow ...... 47 Table 13 : The probability levels of dry season flow in River ...... 48 Table 14 : Main hydrological parameters of proposed dam ...... 49 Table 15 : Water quality measured in 2011 of River (Average) ...... 51 Table 16 : Land use/land cover pattern of the catchment area ...... 58 Table 17 : The land use of the inundation area and 100m buffer zone ...... 61 Table 18 : Air quality data obtained in October, 2011 ...... 64

Table 19 : The measurements of C02 and CO in sampling locations ...... 65 Table 20 : Noise measurements in project locations ...... 66 Table 21 : Land cover types within the catchment area ...... 72 Table 22 : Distribution of the flora according to habitats ...... 74 Table 23 : Distribution of flora according to species & conservation status and habitat ...... 75 Table 24 : Summary of the fauna species according to the habitat ...... 77 Table 25 : Distribution of fauna according to species & conservation status and habitat ...... 78 Table 26 : Summary of the plant species according to plant variety ...... 84 Table 27 : Distribution of flora according to species & conservation status and habitat ...... 85 Table 28 : Distribution plant species according to habitats ...... 86 Table 29 : Summary of the faunal species recorded during the field study ...... 87 Table 30 : Summary of the distribution of the birds according to habitats ...... 88 Table 31 : Distribution of birds according to species & conservation status and habitat ...... 88 Table 32 : Summary of the distribution of the butterflies according to habitats ...... 89 Table 33 : Distribution of butterflies according conservation status ...... 90 Table 34 : Summary of the distribution of the dragonflies according to habitats ...... 90 Table 35 : Distribution of dragonflies according to species status and habitat ...... 91 Table 36 : Summary of the distribution of the mammals according to habitats ...... 91 Table 37 : Distribution of mammals according to conservation status ...... 92 Table 38 : Summary of the distribution of the reptiles according to habitats ...... 93 Table 39 : Distribution of reptiles according to conservation status ...... 93 Table 40 : Summary of the distribution of the amphibians according to habitats ...... 94 Table 41 : Distribution of amphibians according to species status and habitat ...... 94

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir Table 42 : Distribution of the land snails according to habitats ...... 95 Table 43 : Distribution of land snails according conservation status ...... 95 Table 44 : Summary of the distribution of the fishes ...... 96 Table 45 : Distribution of fishes according to conservation status ...... 96 Table 46 : Summary of the recorded other fauna species during the field study ...... 97 Table 47 : The floristic composition and the conservation & species status ...... 98 Table 48 : Population by Grama Niladhari divisions affected by the inundation ...... 102 Table 49 : The sex of the affected population in the study area...... 102 Table 50 : Population by age group ...... 102 Table 51 : Marital status of the population in the affected area ...... 103 Table 52 : No of members in the household in the affected area...... 103 Table 53 : Educational attainments ofe th affected persons ...... 103 Table 54 : The occupational trends of the affected persons ...... 104 Table 55 : The ownership assets of the affected population...... 105 Table 56 : Sources of income of the affected population...... 105 Table 57 : Total monthly income of the affected persons ...... 106 Table 58 : Pattern of expenditure of the affected families ...... 107 Table 59 : Livestock owned by the affected people ...... 108 Table 60 : Availability of water for the affected people for different uses ...... 109 Table 61 : The socio environmental problems prevailing in the affected area ...... 110 Table 62 : Typical values of noise produced by common vehicles and equipment ...... 113 Table 63 : Types of equipment/machinery/vehicles for construction ...... 114 Table 64 : The assessment of the noise modelling data ...... 115 Table 65 : Reservoir inflow and environmental release ...... 123 Table 66 : List of proposed plant species for afforestation ...... 127 Table 67 : List of proposed plant species for understory afforestation ...... 128 Table 68 : Proposed plant species for afforestation at riverine areas ...... 128 Table 69 : Extent of forest inundation and afforestation ...... 129 Table 70 : Details of near threaten fauna species related to classified land covers ...... 136 Table 71 : Critically endengered fauna species and their habitats ...... 139 Table 72 : Land cover types in inundation area, study area and catchment area...... 140 Table 73 :Total lost habitat of each critical endangered species ...... 141 Table 74 : Mitigation of air pollution during construction period ...... 143 Table 75 : Environmental management plan (EMP) ...... 150 Table 76 : Cost estimate for mitigation measures proposed in the project ...... 159 Table 77 : Sub estimates for afforestation and boundary demarcation aren show in ...... 160 Table 78 : Cost breakdown of Per Aru impounding reservoir ...... 161 Table 79 :Computation of expected annual revenue of the project ...... 162 Table 80 :Cost benefit analysis of the project ...... 163 Table 81 : IRR values under benefit cost analysis of the project ...... 165 Table 82 : Environmental monitoring plan ...... 170

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

LIST OF FIGURES

Figure 1 : Location of the proposed reservoir over 1: 50,000 topographical map...... 11 Figure 2 : Forest classification of the forest conservation department ...... 12 Figure 3 : Wildlife conservation sites declared by wildlife conservation department ...... 13 Figure 4 : Potential areas for land to land compensation ...... 18 Figure 5 : Proposed reservoir and forest classification in the Vavuniya District ...... 27 Figure 6 : Forest cover within the upper catchment of the Per Aru ...... 28 Figure 7 : Classified land cover/land use map of the catchment area ...... 29 Figure 8 : Biotic study area and the inundation area ...... 30 Figure 9 : Geology of the study area ...... 31 Figure 10 : Locations of bore holes and test locations of air quality ...... 33 Figure 11 : Geotechnical condition of the dam ...... 34 Figure 12 : Agro Ecological Regions of the surrounding area ...... 36 Figure 13 : Existing water bodies and streams ...... 39 Figure 14 : Mineral resources map of the Northern Province ...... 40 Figure 15 : Mean monthly rainfall distribution in Vavuniya...... 41 Figure 16 : Mean monthly evaporation distribution at Vavuniya from 2001 to 2008 ...... 43 Figure 17 : Water level at gauging station (morning) ...... 44 Figure 18 : Water level at gauging station (evening) ...... 45 Figure 19 : The varaition of the minimum flow between the most dry months of the year ...... 47 Figure 20 : The flood hydrograph of 100 year return period ...... 48 Figure 21 : A longitudinal section of the river reach ...... 50 Figure 22 : Types of aquifers within the reservoir area ...... 52 Figure 23 : Ground water quantity map of the reservoir area ...... 53 Figure 24 : Salinity concentration of the ground water at the reservoir area ...... 54 Figure 25 : The water quality in the ground water in Vavuniya ...... 57 Figure 26 : Land use/land cover of the catchment area ...... 59 Figure 27 : Land use/ land cover of the inundation area and the 100 m buffer zone ...... 60 Figure 28 : Land use development potentials of the area ...... 62 Figure 29 : Proposed elephant corridor ...... 68 Figure 30 : Wildlife reserves, sencuries and proposed jungle corridor ...... 69 Figure 31 : Proposed elephant corridor and inundation area ...... 70 Figure 32 : The habitat types in the inundated area ...... 80 Figure 33 : Proposed locations for afforestation ...... 130 Figure 34 : Proposed elephant corridor and moving path of animals ...... 132 Figure 35 : Reservoir boundary over the elephant corridor ...... 133 Figure 36 : Transect survey lines over classified land cover and land use areas ...... 5 13 Figure 37 : Grievance redress process ...... 145

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

EXECUTIVE SUMMARY A. Background 1. The Report presents the results of studies on the environmental impact assessment (EIA) of the proposed Per Aru Reservoir and Water Treatment Plant located in the Sastriloolamkulam Grama Niladhari Division (i.e. smallest administrative level within a district) in Vavuniya District of Sri Lanka. The proposed project is an integral component of the ADB Assisted Dry Zone Urban Water and Sanitation Project to be executed by National Water Supply and Drainage Board (NWSDB) with the intention of facilitating sustainable development in underprivileged districts in Sri Lanka. The Project expects to achieve its objective for providing safe drinking water and sewerage/sanitation facilities in selected urban and rural areas namely, Mannar, Vavuniya, Puttalam and Chilaw. The EIA study has been conducted by a team of experts in the field of ecology & forestry, water resource & sanitation engineering, social development & resettlement, surface water hydrology, ground water, geology, soils, and air & noise pollution etc. The study period was 8 months from June 2011 to January, 2012. 2. A part of the proposed reservoir area falls on the southern border of a proposed jungle corridor. The Integrated Strategic Impact Assessment carried out in 2011 suggested to establish this new jungle corridor connecting the wildlife Sanctuary of Giant Reservoir from the North West part of the country to the proposed Padaviya Forest Reserve from the North East part of the country. However, the location (Figure 35) of the reservoir has been selected to ensure that it does not obstruct the proposed new jungle corridor. Further, the agricultural areas of three minor irrigation reservoirs namely, Odavysinnakulam, Paranatakkal and Periyakulam will be affected by the inundation of the proposed reservoir which will be replaced as part of the resettlement compensation package for the affected families. B. Project configuration 3. The project envisages surface water extraction by constructing a storage reservoir with a 3 km long and 10 m high earth dam across Per Aru, one of the tributaries of the river Parangi Aru which flows to Indian Ocean at North Western part of the country. The proposed project will also comprise a water treatment plant which is located at immediate downstream of the reservoir. The project is located at the village Sastrikoolamkulam which is about 12 km away from the Vavuniya Town to north western direction. The reservoir will collect the seasonal runoff flow of the Per Aru and distribute treated water to the urban areas of the Vavunia District. The storage capacity of the reservoir is 3.85 MCM at its Full Supply Level (FSL) which is 71 m above the mean sea level (MSL) and daily water abstraction rate is 6700 cu.m. The reservoir proposes to inundate 168 ha of land when the water level is at its designed High Flood Level (HFL) which is 72 m above the MSL. C. Project impact area and the study area 4. The project directly impacts on the area of inundation, water treatment plant and to the downstream river section until it meets the next tributary called Turumpamaddai Aru which is 12 km away from the dam. According to the Environmental regulations, there should be a buffer zone for any water body and accordingly a 100m buffer area along the periphery of the inundation area has been allocated in the proposed project. The impact of the project is assessed by considering a study area of 1066 ha which extends to both upstream and the downstream of the proposed reservoir. The study area considered at the upstream consists of the inundation area and 500 m buffer zone outside the inundation area. At the downstream, sample study was extended to 2.5 km along the Per Aru with a lateral coverage of 500 m either side of the river. Figure 8 shows the study area with major project components.

ii National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

D. Project justification 5. The projected water demanding population may increase to 76,701 in 2030 from 35,958 at present. The water abstraction rate which would be required to supply this demand is around 21,000 cum/day. A maximum of 3000 cum/day is planned to be extracted from ground water sources whereas the rest has to be sought from surface water sources. The existing pipe born water supply scheme in Vavuniya comprises with11 ground water wells of which only 8 are in operation at present. The dearth of water can cater for 2-3 hour supply per day with the extraction rate of about 400 cum/day of treated water against 1500 cu.m per day. The quality of ground water is not as good as the quality of surface water because ground water contains high levels of calcium, magnesium etc. contributing to hardness and subsequently leading to diseases. Already the number of cases with Chronic Renal Failure is increasing in Vavuniya District. 6. In order to explore the available of surface water resources in close proximity, several alternatives were considered at the feasibility study stage under the ADB TA 4853 - Small Town and Rural Arid Areas Water Supply and Sanitation. Feasibility of pumping water from the largest irrigation reservoirs located in the Vavuniya District named Pawatkulam reservoir was studied. This reservoir has been exclusively used for irrigated agriculture with the present average copping intensity (CI) of 1.0 whereas the maximum expected cropping intensity of irrigated agriculture is standardized to 2.0 by considering two cultivation seasons which are dry season and the wet season. The CI can be increased to 1.3 only by improving irrigation efficiency. However, both the Irrigation Department and farmers have objected to this option. A similar situation was shown in the feasibility study carried out in the Vavunia District for pumping water from another two reservoirs namely, Irateperiyakulam reservoir and Vavuniya Kulam reservoir of which CI was even less than 1.0. Another alternative water source was studied at the Tekkama Anicut (Anicut refers the diversion weir) across Malwathu Oya (Oya refers perennial stream) located to the west of Vavuniya town. Tekkama Anicut presently diverts water to two major irrigation reservoirs named as Giants Reservoir and Akathimuruppu reservoir through diversion canals. The Vavuniya water supply scheme is located at about 35 km away from the Tekkam Anicut and 104m above the proposed water intake at the Tekkama Anicut. The salient factors such as high lift, long distance and limited water during the dry months hampered the use of water in the Malwathu Oya at the Tekkam Anicut 7. Another feasibility study was carried to explore the available surface water resources of Per Aru. Hydrological model studies were carried out by using daily rainfall data from 1979 to 2010 (31 years) to assess the surface runoff from the catchment area at the proposed location of the dam. Feasibility of 04 optional models was tested. Option 4 showed that the water supply demand of 1200 cu.m per day could be met exclusively from the surface water by keeping the full supply level at 71 m MSL at reliability of 90% probability level. The bed rock of the designed location of the spillway was exposed to a length of more than 100 m. Therefore foundation condition was very much favourable for the radial gated concrete spill way with 03 radial gates of 6 m x 4.35 m. A biotic survey was carried out to assess the flow regime that is needed to meet its socio-cultural and ecological needs. The river has been not used for any human needs such as irrigated agriculture, fishing, drinking, washing or bathing. A comprehensive study has been carried out to assess in stream flow needed to sustain the ecosystem functions that native fish and wildlife species depend upon to survive and flourish. By considering hydrological conditions, engineering design requirements, social needs and ecological sustainability the project was found feasible. E. Physical and biological environment 8. Physical environment of the reservoir location was studied by focusing on the study area detailed in section B of Chapter III. The Vavuniya District falls within the Dry Zone of Sri Lanka where tropical dry climate is prevalent. The Per Aru basin falls within the DL1 Agro

iii National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir ecological zone with reference to the agro ecological map 2004 as shown in Figure 12. The annual rainfall in the District varies from 1000 – 1500 mm, and experiences heavy rains from October to December during North East monsoonal season. In comparison, amount of rainfall received during the rest of the months is considerably low. The elevation of the topography ranges from 0 - 125 m near the coast and 125 – 750 m at the central part of the district from the average mean sea level (MSL). In general, the Reddish Brown Earths (RBE) and Low Humic Gley Soils (LHG) occupy the area. 9. The total land area covered by the buffer zone and the reservoir inundation is 315 ha of which 80 ha is agricultural land (25%) and 235 ha is different kinds of forest (75%). Out of the 229 ha of the proposed inundated area 168 ha (73%) of forest cover will be lost. The designated buffer area around the reservoir is 86 ha of which currently 66 ha (76%) is forested. 10. A part of the study area comprises Dry Monsoon Forest and Riverine Forest as classified by the Department of Forest Conservation. Significant impact is presumed from the development of the proposed reservoir which will result in the loss of 168 ha of forest comprising of riverine forest, dry mixed evergreen forest and scrub forest. About 1559 trees which belongs to major genera Kumbuk (Terminalia arjuna), Palu (Manilkara hexandra), Weera (Drypetes sepiaria), Mee (Madhuca longifolia), Timbiri (Diospyros malabarica), Damba (Syzygium spp), Hurimara (Albizzia odoratissima), Koon (Schleichera oleosa) will have to be removed from the inundation area of the reservoir. 11. The type of faunal and floral species was recorded in the field study area during the field survey. Impact of recorded species in the standard categories of endemic, critically endangered, endangered, and vulnerable was critically evaluated to propose mitigation measures. F. Socio economic environment 12. The study area encompasses two administrative divisions, namely, Vavuniya and Vavuniya South. The catchment area of the proposed reservoir falls within the Vavuniya South Division, while the reservoir and its downstream within the Vavuniya Division.The project affected families are mostly rural, and many of them depend on agriculture for their livelihood. Unemployment is high (20%) among them and could be attributed to slow growth of agro-based industries and the lack of employment opportunities in the area. 13. Ninety three percent of the affected families are Tamils. The remaining ethnic groups are Moors (5%) and Sinhalese (2%). The majority (78%) of affected families is nuclear families, and 22% are extended families. There are 34 vulnerable households among the affected families including 13 female-headed families. No family will be physically displaced because of the sub project. It will however affect 03 temporary houses (huts), 06 masonry wells, 05 ground water wells, and 01 Hindu kovil (temple). 14. The subproject will impact on cultivated lands causing economic displacement of to 107 families. The inundation area of the proposed reservoir and the 100-m buffer zone around it cover 334 ha of land of which 79 ha are paddy land. On 23 ha of the remaining land, farmers cultivate seasonal crops under chena (slash-and-burn) cultivation method. There are 130 claimants to these agricultural lands of 102 ha either sole or joint land users. They are members of the affected 107 families. Nineteen percent of claimants possess land title deeds, while 17% hold 'cultivation permits' from the Government. Another 3% received land grants or “Jayaboomi” deeds from the Government. 24% of claimants are registered as 'cultivators' at the Agrarian Service Center. The other claimants (37%) do not have any documents to show their rights over the land they possess and cultivate. The Resettlement Plan 2012 of the subproject indicates that 54% of the claimants have been cultivating the land for more than 25 years, while 9% have started cultivation within the past 5 years. The

iv National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir project authorities will provide land for claimants under the land-for-land compensation package. G. Archaeological and cultural considerations 15. There are no archeologically designated areas in the proposed reservoir site. However, there are many places of historic and archaeological value in the Per Aru upper catchment area. With regard to religious and cultural values, there is one small kovil located in the affected area and two more trees used for worshiping. H. Key environmental impacts and mitigatory measures 16. Major impacts of the project during construction and reservoir inundation were studied and analyzed carefully. While most of such impacts have been addressed in the EIA Report, some additional investigations are required to be conducted on critical endangered and endangered species, their habitat and its overall management in the context of the project site and the overall study area constituting both downstream and upstream areas from the proposed reservoir. 17. The key environmental impacts anticipated from the proposed project are (i) disruption to ecological system, (ii) disturbance to land surface, (iii) changing the Per Aru river flow pattern, and (iv) economical displacement of 107 families. 18. Due to the construction of the reservoir, about 168 ha of forest which belongs to the categories of dry monsoon forest (146 ha), open sparse forest (18 ha), and scrub lands (4 ha) will be inundated. A tree survey estimated about 1559 of mature trees in the inundated areas will be uprooted. While it would be hard to mitigate this loss, by way of compensation it has been proposed to plant trees over an extent at least equivalent to the forest area which will be inundated. 19. Forest Conservation Department (FCD) has classified the forest cover within the catchment area under the categories of dry monsoon forest, open & sparse forest, shrub jungle, and non forest. Within the non forest area of FCD map, there exist land cover /land use types classified by the Survey Department (SD) topographical map of 1:50,000. They are scrub jungle, garden, paddy, water bodies and grasslands. The “non forest” classified for grasslands was selected for afforestation. The suitable areas for afforestation of the project was selected by considering areas adjoining to the existing forest cover types which were similar to the affected forest cover types inside the inundated area. For the afforestation of riverine type, river banks of two streams which join to the Per Are at the upstream were selected within the residual area. 20. While recommending plant varieties for afforestation, care will be taken to factor such plant species which will be lost due to inundation, agro-ecology of the re-plantation areas. Availability of recommended plant types in the nurseries will also be considered. There are 279 plant species in total including 92 trees, 25 shrubs, 95 herbs, 4 epiphytes, 63 climbers/creepers that will be lost due to inundation. Among them there were 11 endemic species, 4 vulnerable species and 2 endangered species associated with the dense forest, open scrubland, river and riverine and Reservoir associated habitats. Out of these aquatic species are most affected. Cryptocoryne beckettii, (Ati Udayan) an aquatic plant which occurs in the river and associated localities will lose its habitat however, it is prevalent widely in similar habitats in the region. Kaluwara (Diospyros ebenum), which occurs in the riverine habitats is an endangered tree species but it occurs in similar habitats in the region. 21. A total number of 316 faunal species including 28 endemic, 03 proposed endemic, 3 critically endangered, 1 endangered, 11 vulnerable and 19 near threatened species were recorded in the field study area during the field survey. Three recorded species namely, Mycalesis visala (a butterfly), visala Euplecta colletti (land snail) and Japonia vesca (a land snail) were identified as critically endangered. One land snail species Theobaldius

v National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir subplicatulus was identified as endangered. Among the mammals there are many endemic species which are also nearly threatened and vulnerable in the habitats which will be lost due to reservoir construction. They are Sri Lanka Toque Monkey, Purple faced Leaf Monkey, Grey Langur, Elephant, Jungle Cat, Fishing Cat, Grey Slender Loris, Pangolin, Otter, Parker’s Black Turtle, Indian Star Tortoise, Flapshell Turtle). They will be greatly affected during the construction phase of the project but the impact will be reduced during operation stage. As there are other conservation areas existing in close proximity of the reservoir such as Melkulam forest reserve, Padaviya forest reserve and Gients sanctuary the impact will be much reduced. Due to the high mobility of the birds, dragonflies and butterflies they will be less affected. The ecological impact will not make significant impediments to animal movements in the corridor especially the elephants as the reservoir will be filled up to the full supply level only during the seasonal rains of the North East monsoon (November to February) and during the rest of the months there will be ample room for movement across the corridor. Even during the former months elephants are able to cross the waters. The Melkulam Forest Reserve located on the northern side and the scrub forests located in the southern side will facilitate animal movements along the corridor without threatening the neighboring community. In addition, no fence will be erected around the reservoir to facilitate consumption of water by migratory animals through the area. However, during the construction stage, some impacts are anticipated. Safety of the workers and the neighboring community can be jeopardized if migration of elephants through the area is not managed properly during construction stage. It is proposed to observe and note the migration path and timing of the elephants in the area and accordingly arrange common transport facilities for the workers within pre-arranged time periods such as once in the morning and once in the afternoon. Transportation of material, goods and machineries/equipments across the jungle corridors shall also be controlled on the basis of observation of the regular movements of animals. Additional security measures shall be provided along the border villages bounded to wildlife corridors by consultation with the department of wild life conservation. 22. Additional ecological survey and study will be carried out to ensure the protection measures of endangered and critically endangered species. A report on biodiversity and critical habitat protection and management will be also prepared before the award of contracts. 23. As a result of land clearing and earth excavation for construction purposes, soil erosion, surface & drainage water pollution, water stagnation and sedimentation will take place. Construction of soil conservation bunds, silt traps and regular cleaning of drainage paths are proposed. Suitable soil material is required for the formation of the earth dam. Soil investigation is proposed to be carried out within the inundation area to check its mechanical properties. The leaves and branches which will be left after removal of trees within the inundation area can be used for the bottom filling of the burrow pits before reinstating them. Adequate care will be taken to protect the surrounding environment and maintain the sediment and erosion control measures during the construction period by conducting labor awareness programs and establishing a regular surveillance program. Water quality tests will be carried out in regular intervals as specified in the environmental monitoring program to ensure appropriate measures are taken for any potential breaches to meeting the national water quality standards. 24. The water extraction at the weir site will impact the water supply downstream of the weir especially during the dry season. There are three endemic fish species in the river (Flying barb, Bearded rasbora, Lanka labuca and Filamented barb) and one nearly threatened species (Climbing perch). Due to the reservoir loading and the reduced flow to the downstream viability of these species may be impacted. This impact has been mitigated to a certain extent by releasing an environmental flow which varies from a minimum flow of 0.038 cu.m/sec to a maximum flow of 0.1538 cu.m/sec during the entire year. Measures e.g. fish passes will also be installed in the dam to facilitate fish migration. The impact of tapping

vi National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir the stream for the other downstream users is not very significant as there are no legal water users of the river for cultivation of paddy in the downstream river. Further, the river is not being widely used for bathing, fishing or any other activity as there are many minor irrigation reservoirs in the downstream used by the local people. After about 08 km from the bund, Turumpamaddai Aru tributary will join the river enabling resumption of normal flow. 25. The inundation of proposed reservoir will affect the irrigated agricultural lands belonging to 107 families. A resettlement plan has been prepared addressing the economical displacement issues and appropriate mitigation measures have been recommended in the plan. Alternative lands along the outside periphery of few abandoned irrigation reservoirs have been identified by the district administration as replacement for the affected areas. Department of Forest Conservation is currently undertaking assessment of this alternative land in terms of its forest value which needs to be completed prior to the release of these lands. 26. Also impacted from the project are the occupants of 3 temporary houses located in the buffer zone who will have to be relocated. Resettlement plan prepared for the project has made appropriate compensation provisions for affected occupants of these dwellings who are not the legal owners of this land. I. Environmental management and monitoring plan 27. An environmental management plan (EMP) has been prepared to summarize the project impacts, mitigation measures and identify responsible authority for each of the activities corresponding to impacts. The performance indicators of the EMP are closely related to the monitoring plan. A number of parameters related to engineering, hydrological, biological and social aspects have been selected for monitoring during the construction and operational phases. Bi-annual monitoring reports will be submitted to CEA and ADB by NWSDB for verification of project performance. J. Conclusion and recommendation 28. Having assessed the key positive and negative environmental impacts and identified possible mitigation measures in this EIA report, the study team concludes that the project may go ahead with due consideration of the recommended mitigation measures and the monitoring mechanisms proposed. Outcome of the additional ecological study and finalization of the land to land survey for agricultural practices of the affected farmer community will be added as a supplement to the current EIA report.

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

I. INTRODUCTION

A. Background of the project 1. The proposed project is an integral component of the larger ADB Assisted Dry Zone Urban Water and Sanitation Project that intents to facilitate sustainable development in disadvantaged districts in Sri Lanka. The Project hopes to achieve its objective by investing in priority water supply and sewerage/sanitation infrastructure in selected urban and rural areas in addition to the institutional reforms and capacity development of water sector institutions. The total project cost is US $ 113.33 Million. Chosen urban areas are the towns of Mannar, Vavuniya, Puttalam and Chilaw. The Project implementing period is from June 2009 to June 2014. The Ministry of Water Supply and Drainage is the Executing Agency for the Project and the National Water Supply and Drainage Board (NWSDB) is the implementing Agency. B. Objectives and justification of the project 2. Improvement in water supply is required in Vavuniya because the present infrastructure is inadequate for satisfying the needs of the growing population. The present water supply system was based on groundwater extraction from 08 ground wells (4 shallow wells of large diameter and 4 wells of small diameter and relatively deep). 3. In an effort to improve the resources, additional drilling was done in 2003 mainly in the immediate town area and 3 deep tube wells were eventually developed and turned over to the NWSDB for the town water supply. The town water supply now comprises 11 wells. However, only 8 of them can presently be operated due to the low efficiency of the pumps. 4. The distribution system is beset with leaks and water is available only 12 hours a day in the wet season which is restricted to 3 to 4 months and during the rest of the year water supply is restricted to 2-3 hours a day. Few existing ground water wells, which are located near Vavuniya irrigation reservoir, are extremely vulnerable to pollution from agrochemicals and also from the sewage and from other liquid or soluble contaminants. 5. With the end of the 30 year war, Vavuniya is becoming more and more popular for living and it is projected that the water demanding population may increase from 35,958 at present to 76,701 in 2030. The water extraction rate which would be required to supply this demand is around 21,000 cum/day and from this a maximum of 3000 cum/day can be procured from ground water sources, and the rest has to be sought from surface water sources. 6. After evaluation of the feasibility of 04 alternative studies that have been conducted to explore the available surface water resources, tapping the waters of Per Aru, which is a tributary of Parangi Aru, has been found feasible. The mean in flow during the rainy months of Maha Season (Wet Season) ranges from 6.85 MCM in December to 2.25 MCM in January, after which it varies between 0.3 MCM and 0.1 MCM. The overland flow during the seasonal rains can be stored by constructing a dam across Per Aru and used for supplying safe drinking water. The land use of the area is predominantly forest while some agricultural lands also remain. There are no houses within the potential inundated area of the proposed reservoir. C. Objective of the EIA report 7. The overall objective of the EIA is to achieve sustainable development in the context of harnessing the waters of the Per Aru basin for human welfare and for the health of associated ecosystems.

2 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

8. It is a statutory requirement to obtain formal environment approval for Prescribed Projects of certain magnitude published in the Government Gazette Extraordinary No. 772/22 of June 1993under the provisions of National Environmental Act No 47 of 1980.In pursuance of this requirement the NWSDB, being the project proponent, was expected to conduct an EIA on the proposed Per Aru reservoir based water supply project. . The aim of the present EIA study is to conduct a comprehensive investigation of all aspects of the proposed project and assess its impacts in conformity with the Terms of Reference (TOR) established by CEA. 9. The present EIA study identifies the significant impacts, (both positive and negative), potential risks and appropriate mitigation measures while also conducting an extended cost- benefit analysis of the project. 10. The specific objectives of the EIA Report include the following: a. Identification of the impact areas b. Comparison of reasonable alternatives c. Evaluation of significant environmental impacts on the bio-physical, socio- economic and cultural environment d. Recommendation of measures for mitigation of negative impacts e. Analysis of the environmental costs and benefits f. Preparation of a monitoring plan to be implemented by appropriate agencies over the construction and operation stage of the project. D. Methodologies and technologies adopted for preparation of the EIA report 11. Environmental impacts of the Project were assessed through reviewing existing information, conducting field investigations and collection of spatial and non-spatial data and by using standard evaluation techniques adopted from Leopold Matrix.

1. Survey of existing literature 12. Following relevant literature sources were reviewed; • Feasibility studies conducted for by M/s Nippon Koei in association with IDP Consult Inc. for identifying water resources for the Small Towns and Rural Arid Areas Water Supply and Sanitation Project (the previous name of the Project) and published in March 2008. • Initial Environmental Examination (IEE) conducted in 2008 by M/s Nippon Koei in association with IDP Consult Inc., for the project in Vavuniya town under the Small Towns and Rural Arid Areas Water Supply and Sanitation Project (ADB TA 4853 – SRI)funded by the Asian Development Bank • Short investigation report prepared by M/s RDC in association with M/s NIRAS, in January 2011, on water supply to the urban area of Vavuniya by the ADB Assisted Dry Zone Urban Water and Sanitation Project Package C. • Interim Report of the ADB Assisted Dry Zone Urban Water and Sanitation Project Package C, prepared by M/s RDC in association with NIRAS, in August, 2011. • Policies, Acts and other legislative instruments applicable in water

3 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

supply and in particular reservoir construction and implementation.

2. Field investigations 13. Field studies were carried out by the consultants in order to gather new information and to verify/update existing information. The studies conducted on physical, biological and sociological parameters of the Project were used for the EIA study and wherever necessary additional studies were conducted. Field sampling was carried out in areas selected after the examination of all available information. Laboratory tests were conducted to supplement the existing information where there were significant issues. The purpose of the field survey and laboratory tests was to fill the gaps in the existing data and to verify their accuracy. 14. The project directly impacts the upstream inundation area and also the downstream river section until it meets the next tributary called Turumpamaddai Aru which is 08 km away from the proposed dam. According to the environmental regulations, there should be a buffer zone of 100 m wide adjacent to the periphery of the inundation area of any water body when it is at the full supply level. 15. The biological survey included survey of Flora species in different land cover areas and Fauna species together with their habitats in land areas, river section and water bodies. The impact of the project extends to both upstream and the downstream of the proposed reservoir. 16. The biological survey included survey of flora species in different land cover areas and fauna species together with their habitats in land areas, river section and water bodies. The study area was chosen considering the climatic and geographical aspects of the site and its environs and on the assumption that the impact of the project can potentially extend to both upstream and the downstream of the proposed reservoir. Accordingly, the upstream boundary of the study area was determined to cover 500m around the full supply level (71m MSL) of the reservoir and on the downstream of the reservoir, 2.5 km along Per Aru river from the reservoir with a lateral cover of 500m on either side of the river.

a. Biotic survey

17. Over the study area, the sampling intensity and sampling sites for each habitat/land use type was determined by categorizing as degraded forest and water body associated vegetation. The detailed survey was carried out with both day and night time sampling in each identified sampling location in order to assess and document the biotic resources within the study area. This survey included field sampling of both aquatic and terrestrial fauna and flora using variety of methods suitable for such a rapid biodiversity assessment.

i. Fauna

18. Line transect survey method was used to assess the terrestrial fauna and plot survey method was used to assess aquatic fauna within each identified habitats in the study area. Several techniques were used to collect information within transects or plots on the main selected taxonomic groups, namely, dragonflies, butterflies, land snails, freshwater fish, herpetofauna (reptiles and amphibians), birds and mammals. The observed animal species were identified by using the most recent published descriptions and taxonomic keys such as by D’Abrera (1998), Bedjanic et al., (2007), Harrison (1999), Phillips (1935), Kotagama (2005), Goonatilake (2007), Fernando (1990), Naggs and Raheem (2000), Manamendra- Arachchi and Pethiyagoda (2006), Das and De Silva (2005), Somaweera (2007), Somaweera and Someweera (2009). The national conservation status of the species was recorded according to the 2007 Red List of Threatened Fauna and Flora of Sri Lanka (IUCN & MENR, 2007). Nomenclature of the fauna was based on Bambaradeniya (2006).

4 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

ii. Flora

19. Gradsect (gradient-directed transect) sampling technique was used to gather data on plant diversity. Plots of 100-m x 5-m were carried out within each identified habitats to asses terrestrial flora in the study area. The higher plants and selected lower plants (Bryophyta and Pteridophyta) observed within each plot, were identified to their families, genera and species. Specimens of unidentified species collected and numbered for subsequent identification at the National Herbarium of the Department of Agriculture, Peradeniya. Identification of the observed plant species were based on published descriptions and taxonomic keys provided by Dassanayake and Fosberg (1980-1991), Dassanayake, Fosberg and Clayton (1994 -1995), Dassanayake and Clayton (1996-2000), Dassanayake, Clayton and Shaffer-Fehre (2006). The national conservation status of the species was recorded according to the 2007 Red List of Threatened Fauna and Flora of Sri Lanka (IUCN & MENR, 2007). Nomenclature of flowering plant was based on Senaratna (2001).

3. Geological investigations 20. Underlying geology and geomorphology (regional and local geological structure, presence of active linear faults and rock mass strength, leakage conditions, land slide potentials, occurrence of minerals, availability of groundwater etc.), geophysical investigations were carried out by resistivity method at selected locations along the bund. Field observations and geological information extracted from maps were used to interpret the geo-morphological situation of the Project area.

4. Soil study 21. Soil types and their characteristics (soil depth, drainage, stability, fertility etc.) to determine the land suitability and stability were studied by observing bore hole samples taken at selected cross sections. Data were interpreted with identified soil series and by using published data tables.

5. Study on surface water quality 22. Surface water quality was determined by testing the samples collected from the project area for the physical, chemical, and biological water quality parameters. The results were compared with the Sri Lankan Standard for Drinking Water Quality (SLS 614:1983)

6. Study on ground water quality 23. Ground water quality was studied by testing the samples collected from 08 wells in the study area for chemical analysis. The results were compared with the Sri Lankan Standard for Drinking Water Quality (SLS 614:1983)

7. Study on air quality 24. While there are no major concerns over air quality in the vicinity of the project area (the nearest habitated village being 2.5 km away from the site), baseline conditions were measured at the project site for comparison with national standards and any potential future impacts. Air quality parameters included suspended particulate matter (SPM), particulate matter less than 10 micro grams (PM 10 ), SO2 , NO2, obtained as a 24 hour average and CO, CO2 obtained from one hour samples at the three locations identified in the project area and environs (Figure 10). These measurements were carried out by the Industrial Technology Institute (ITI). Results were compared with the Maximum Permissible Ambient Air Quality Levels stipulated by the Central Environmental Authority under the Gazette Extraordinary No. 850/4, dated 20, December 1994.

5 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

8. Study on noise and vibration 25. The noise and vibrations were recorded in four locations (Figure 10) of the project area. Two hour measurements were taken at each location between 10.00 to 18.00 hrs during the day time while one hour measurements were taken between 19.00 to 21.00 hrs during the night time. The data were compared with Noise and Vibration Standards set by the Pollution Control Division, of Central Environmental Authority (25/02/2004). In anticipation of the noise that will be generated by the use of machinery and equipment during the construction phase and also during the implementation phase, a modelling exercise was carried out and a noise map was generated by the ITI.

9. Observations on archaeology 26. Visual observations of potential archaeological impact areas under the proposed project were made. In addition to this, due documentation was lodged with the Department of Archaeology in connection with archaeological clearance.

10. Spatial data 27. The following topographic maps were procured from the Survey Department: a. 1:50,000 scale topographic maps with contours at 20 m intervals. Sheets covering the Per aru basin are: 16 - Palampiddi; 17 – Padaviya b. District forest conservation map prepared by the Department of Forest Conservation. c. Wildlife Conservation map of the Department of Wildlife Conservation d. Soil and geological maps available in the Survey Department covering the study areas e. Agro-ecological map of the Department of Agriculture, 2004 f. Engineering survey maps prepared in 2011 for the Project by the Survey Department to cover the inundated area of the proposed reservoir and the 100m buffer zone including elevations. g. River valley cross-sections at dam site taken from surveyed map at 100m intervals. Cross-sections of the dam site were taken from the topographic map with 1 m contour intervals.

11. Non-spatial data 28. Data and results of the socio-economic survey carried out for the preparation of resettlement plan of this project by following techniques such as house to house questionnaire surveys key informant interviews, focus group meetings with stakeholders, official meetings held at district offices, consultants scoping sessions by using Leopold Matrix as a tool, and direct field observations were used giving appropriate reference. Socio- economic surveys were conducted for 76 affected families randomly selected out of the population size of 107. Moreover, field studies were carried out for testing of air quality, noise vibration, water quality, and ground water recharging rate. E. Government policy regarding the project 29. At present, the overarching policy governing all development activities of the Government is Mahinda Chintanaya; a development strategy oriented more towards the development of backward rural areas. The northern regions were opened for development largely after the end of the 30 year war in 2009. Afterwards the main development effort introduced to the North was ‘Uthuru Wasanthaya’ (Northern Spring). The development

6 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir program of the ‘Uthuru Wasanthaya’ includes development of infrastructure, resettlement, development of agriculture and other livelihood programs. 30. These programs are being implemented at an accelerated rate under the patronage of the Minister of Economic Development and Chairman of the Presidential Task Force for the North. In Vavuniya, thirty five villages are being developed under the 180 day accelerated program launched by the Government to resettle the Tamil civilians sheltered in the welfare camps and displaced by the conflict. The pre-identified infrastructure of these villages will be improved and that includes provision of drinking water. 31. Nearly 30,000 civilians of 35 villages under the purview of Vavuniya, Vavuniya South, Vavuniya North and Settikulam Divisional Secretariat is due to be resettled immediately after the infrastructure development is completed. Infrastructure facilities for drinking water, electricity, road, health, education, irrigation and agriculture are the main development initiatives. The proposed project is a much needed impetus to the above as it aims at providing much needed safe drinking water to the people who are living in the area and also the people who have newly moved into the area following end of civil war. Therefore, the proposed project is of vital importance and in par with the policy of the Government. 32. Sri Lanka is a signatory to the Declaration of Strategies for Achieving Millennium Development Goals of the United Nations. Goal 7 of the MDG is Ensuring Environmental Sustainability. It has 4 targets of which target 3 deals with halving by 2015 the proportion of people without safe drinking water and basic sanitation. The key indicators are proportion of population with sustainable access to an improved water source and proportion of urban and rural population with access to improved sanitation. 33. The NWS&DB has set its own target to provide safe drinking water to 85% of the whole population by 2010 and to 100% by 2020. The Sri Lanka National Campaign for Achieving the MDGs is spearheaded and administered by the Ministry of Finance & Planning, with the support of the United Nations Country Team and with direct implementation assistance by the United Nations Development Programme (UNDP). 34. The National Drinking Water Policy of Sri Lanka has the vision for a healthy society that values the safety of drinking water and is committed for its sustainable use. It aims at achieving the goals and objectives set by the Government, resolving issues related to qualitative and quantitative aspects and promoting commitment of service providers and users for sustainable utilization of drinking water. It provides guidance to all the actors involved in the sector including Ministry of Water Supply & Drainage, NWSDB, Provincial Councils and Local Authorities, Lending Institutions and External Supporting Agencies, Community Based Organisations, Non-Government Organizations and the users. It directs the NWSDB to undertake design, construction and operation of small, medium and major pipe borne water supply schemes and implement water shed water source protection programmes among many others which are in line with the present project. 35. The TOR of this EIA had beed furnished by the CEA to fulfil the requirements stipulated in the national environment act No. 47 of 1980 and subsequent amendments. The EIA has been prepared in conformity to the said act. There are several national policies that have some bearing on the proposed Per Aru Project and the EIA Study paid due attention to them. and according Some of them are: • National Environmental Policy & Strategies 2003 • National Involuntary Resettlement Policy (NIRP) • National Physical Planning Policy • National Watershed Management Policy • National Drinking Water Policy • National Agricultural Development Policy

7 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

• National Land Use Policy • National Water Resources Policy • National Forest Policy • Wild Life Conservation Policy • Policy on Elephant Management F. Conformity with other development plans in the area 36. Upon a directive given by the Cabinet Ministers in 2002, Integrated Strategic Environmental Assessments (IESA) was conducted for many regions in the country. The most recent attempt focused on the Northern Province and was completed and launched in 2011. During the ISEA exercise conducted by the CEA in the Northern Province, with the participation of all relevant stakeholder agencies, a jungle corridor linking Padaviya Forest Reserve and Giant Reservoir Sanctuary, has been proposed by the DWC. 37. Following consultation with DWC it has provided permission to construct the reservoir including the water treatment plant in the proposed location as the reservoir is bordered by the the southern edge of the proposed jungle corridor. As a measure for mitigation of negative impacts the DWC has advised the NWSDB not to erect an electric fence around the reservoir so that the wildlife can also utilize the water. An electric fence could be erected around the water treatment plant as it occupies a small area (5-acres). In addition to the above, at the meeting of the Technical Evaluation Committee held on 14.5.2012, the DWC requested to include a fish pass to the design to enable free movement of fish and this has also been incorporated into the design. 38. Out of the 250.5 ha of land which will be inundated by the Project, 168 ha is forest land. As classified by the Department of Forest Conservation this forest land comprises of Dry Monsoon Forest (including Riverine Forest), Open & Sparse Forest and Scrub jungle. The other declared forest reserves situated outside and in close proximity to the inundated area are Melkulam Forest Reserve and Rasentrikulam Forest Reserve. The Forest Department has provided permission to build the reservoir in the intended location subject to the acceptance of the EIA. They have further recommended compensatory reforestation for the forest that will be lost due to inundation. 39. A MOU was signed between the NWSDB and Ministry of Agriculture, Livestock Development, Lands, Irrigation and Fisheries of Northern Provincial Council for designing and construction of the reservoir. Another MOU was signed between the NWSDB and Department of Agrarian Development, Vavuniya for conducting a feasibility study for development of alternative paddy lands for economically displaced people in the downstream areas of the proposed reservoir. 40. The project is located in a largely forested area, within which a number of minor irrigation reservoirs are situated. At downstream of each reservoir, there had been an irrigated agriculture command area. Cultivation pattern was restricted to paddy or other field crops (OFC) subject to availability of water in the reservoir and from seasonal precipitation. However, the war effected areas in the North has yet to return to normal conditions with some irrigation reservoirs completely abondonned. 41. The agricultural command areas of three minor irrigation reservoirs namely Odavysinnakulam, Paranatakkaland, and Periyakulam will be affected by the inundation of the proposed reservoir. Therefore, alternative lands which situate along but outside the periphery of the few other abandoned irrigation reservoirs have been identified by the district administration. Prior to releasing the lands, the forest cover assessment survey needs to be conducted by the Department of Forest Conservation and it is in progress.

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9 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

II. DESCRIPTION OF THE PROPOSED PROJECT AND REASONABLE ALTERNATIVES

A. Description of the project

1. Name and location of the project area 1. The Project is located in the Sastrikoolamkulam Grama Niladhari Division of the Vavuniya Divisional Secretariat in Vavuniya District. The project components include the construction of a reservoir with a10.5-m high earth filled dam across the Per Aru (FSL-71 m MSL) located about 12-km north west of Vavuniya Town in Vavuniya District of Sri Lanka. 2. Location map of the proposed reservoir is shown in Figure 1. Only 1:50,000 maps are available to cover the entire project area while survey maps are available for the area inundated by the reservoir and for the proposed 100 m wide buffer zone. The land which will be used for the project is predominantly state owned. The total affected area including inundation area & buffer zone is 333.5 ha. It includes different kind forest, agricultural lands, and water bodies. Of the 107 persons in the affected farmer community who will loose their agricultural lands of nearly 102 ha, 37% do not have any document to claim ownership of land. The Resettlement Plan 2012 of the same project discloses that 54% of the claimants have been cultivating in the said location more than 25 years while 9% have started cultivation within the last 5 years. The agricultural lands are fed by three minor irrigation reservoirs for the cultivation of paddy and other field crops.

2. Key feature of the proposed project

a. Reservoir

3. Key technical features of the reservoir are as follows; Net Catchment area - 42.0 sq km Gross Catchment area - 185.320 sq km Reservoir at full supply level (FSL) - 71 m MSL Reservoir at High Flood Level (HFL) - 72 m MSL Minimum Operating Level (MOL) - 68.0 MSL Bund Top Level (BTL) - 73.5 m MSL Bund Top Width (BTW) - 5.0 m Bund Top Length (BTL) - 3.0 km Radial Gated Spillway Section - 3 Radial Gates (6.0 x 4.65m) with Ogee Crest Sill at 67.5m MSL Labyrinth Spillway (Crest Wall Type) - Crest Sill at 71.0 m MSL of length 135m Flood Diversion Discharge (Both Spillways) - 18,000 cusec (510 m3 /sec) Area inundated at FSL - 238.74 ha Area inundated at HFL - 340.45 ha Capacity at FSL (71m MSL) - 3.849 MCM Capacity at HFL (72m MSL) - 6.691 MCM Capacity at MOL (Dead Storage) - 0.145 MCM Average depth of water - 3.0 m

10 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir The area of the water treatment plant - 2.27 ha Rate of abstraction - 6700 cu.m/day Intake Structure - 5 m diameter RC intake well with 4 m water depth and pump house 4. The forest type of the surrounding area is classified according to the forest classification map prepared by the Forest Conservation Department (FCD) as shown in Figure 2. The existing water bodies including minor irrigation reservoirs and agricultural lands under each reservoir were excluded from the forest cover of FCD map Present Wildlife conservative sites of the surrounding area declared by the Wildlife Conservation Department (WCD) are shown in Figure 3 which indicates that there are no existing wildlife conservative sites in the immediate vicinity of the proposed reservoir.

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Figure 1 : Location of the proposed reservoir over 1: 50,000 topographical map.

12 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

Figure 2 : Forest classification of the forest conservation department

13 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

Figure 3 : Wildlife conservation sites declared by wildlife conservation department

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b. Water treatment plant

5. Water from the reservoir will be treated in the water treatment plant to the standards meeting the national drinking water quality standards for supplying to consumers. The Treatment Plant consists of a series of open and closed RCC tanks spread in an area of around 0.8-ha. This includes an aerator, an up flow clarifier with hydraulic flocculator, a rapid filter chlorinator, and sludge thickener. The proposed treatment plant with a working capacity of 12,000 cum/day is located at the left bank immediate downstream of the reservoir. The treatment plant will primarily treat for color, turbidity, ammonia and total iron in the waters. It will also treat the water for any concerns arising from impoundment including potential taste and odor issues due to algae, and potential anaerobic condition developing at the bottom of the reservoir. The design details of the treatment unit are shown in Table 1.

Table 1 : Design details of the proposed water treatment plant

Process Related Units Description Pre Chlorine Chamber 2 units (or 1 unit with 2 cells) Each unit; approx 4.5 x 4.0 m2 (area in plan) Aerator 1 unit – cascade area of 19 m2 Rapid mixing Hydraulic – horizontal flow thru vertical baffles 2 units each unit approx. 8 x 4.8 m2 (area in plan) Flocculation Tank Hydraulic – horizontal flow thru vertical baffles 2 units each unit approx. 8 x 4.8 m2 (area in plan) Clarifiers with Tube Settlers 2 units each unit approx 15 x 4.8 m2 (area in plan) Rapid Gravity Filter 4 units each unit approx. filter area 5 x 5 m2 Filter media: multi media UC & ES to be determined based on under drain system Backwash: Air & Water Under drain: Low profile type GAC Absorption Tank 2 units. GAC in each tank approx. 4.3 x 4.3 x 4.6 m3 Contact /Clear Water Tank Min 2 hours Flow measurement Plant effluent: Ultrasonic over channel Filter Effluent: Magflow meter Plant Effluent: Magflow meter Chemical Storage 1 unit Sludge Drying Bed 1 unit but 2 cells. Area of each cell 16 x 8 m2 Non process related units Staff housing 1 unit (dimensions) Generator room 1 unit Standby generator and fuel storage

6. Treatment process comprises follow steps; • Pre oxidation with chlorine (for algae, taste and odor removal) • Aeration (to remove the anaerobic condition prior to adding coagulants) • Coagulation • Clarification

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• Filtration • Activated carbon adsorption • Disinfection 7. With regard to the steps for managing the process waste stream, the treatment residuals will be sent to thickening beds, dewatered and then dried in sludge drying beds. The dried sludge will then be disposed from the site at set intervals. c. Water storage, transmission and distribution system

8. The treated water transmission main conveys the treated water from the water treatment plant to ground sump at Nelukkulam for storage. The pipes used will be 9.6 km of 450-mm diameter DI and 5.9-km of 350-mm diameter DI. For the temporary storage of treated water prior to distribution, an RCC tank of 2500-cum capacity (15 mx17 mx10 m), will be constructed 5-m above and below the ground level. This would be erected on government land at Nelukkulam. The pumping main will convey treated water from Nelukkulam Ground Sump (3000 m3) to 03 new overhead towers at Nelukkulam (1000 m3), Puthukulam (300 m3) and Moontrumurippu (1500 m3), and the existing overhead tower in Vavuniya Town. This will be done by using 41 km of DI or PVC pipes of 110-400-mm diameter lay in trenches alongside paved public roads in the town. 9. High lift pump houses will be erected to pump treated water from the water treatment plant to Puthukulam overhead tower and Nelukkulam Ground Storage tank. High lift pump houses will be erected to pump treated water from Nelukkulam ground sump to 03 overhead towers at Nelukkulam, Vavuniya and Moontrumurippu. This will be a brick and a 4-mx3- mx3-m masonry house containing 2 pumps of 4700 cum/day capacity erected on government land at Puthukulam and Nelukkulam. Treated water will be distributed to the customers via 95-km of UPVC pipes of 90-160 mm in diameter. They will be buried in trenches alongside public roads in the part of Vavuniya administered by the Divisional Secretary. In order to store water prior to distribution and provide a head of water for distribution by gravity, new overhead reservoirs will be built.

3. Temporary constructions and construction material

a. Contractor’s and engineer’s site office

10. To perform construction activities, site offices for both contractor’s staff and engineer’s staff are required. Temporary buildings are to be constructed at the downstream of the dam with adequate sanitary facilities. Labour camps and other temporary buildings

11. For efficient stock management in construction, separate buildings and yards will be required for stocking pipes, fittings and electro mechanical items etc. Labour camps are to be constructed by providing adequate sanitary facilities. A fleet of earthwork machinery, hauling equipment and other equipment such as rock drilling machines will be in operation throughout the construction period. At least one work shop will be required close to the dam site.

4. Methodology of construction of Per Aru reservoir

a. Site preparation activities

12. Sites, where the permanent structures are to be located, will be cleared of all vegetation and top soils. Areas coming under access roads to construction sites and temporary establishment will be thinned of vegetation and trees will be cut only where

16 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir facilities will be constructed so that sites can be rehabilitated later to its original condition by planting trees. 13. The Dam consists of an impervious centre core and a more pervious Clayey Sand material. All zones are laid together layer by layer, initially after laying the sand blanket in the downstream section of the dam. The chimney filter is constructed by excavation to manageable depths and by filling with sand. Following activities will be encountered in preparation of site. • Removal of vegetation and top soil with root zone to prepare the base of dam. • Removal of overburdened, weathered rock down to about 10-m up to the slightly weathered or fresh rock for the cut off trench. • Grouting with cement slurry to seal possible fracture in rock. • Filling of the core trench with Silty Clay impervious material in the river section up to the gated spillway. • The results of geotechnical investigations indicated that presence of sandy layers at deep horizon of the dam section. This material may result significant seepage losses and ground water level is also high. Removal of this material will require costly deep excavations in account of dewatering requirements. Due to these constraints it was decided to provide 1 m wide cutoff wall with soil betonite slurry up to a rock layer having relatively low permeability. This cut off wall will cause to minimize the seepage losses. b. Facility construction

14. The overburdened and highly weathered rock will be excavated, to a depth between zero and a few meters under the dam, in order to provide seepage control cut off trench/Bentonite Slurry Wall. On the embankment a deep excavation of up to 10 m will be required in sections to remove the pervious material such as Silty Sandy clay and highly weathered rock, (generally the amount of excavation varies from 0.5 m to 10 m.) Groundwater table varies from 1.5 m to 5.5 m and dewatering will be required during construction. 15. During the dry seasons (from May to September) of the construction phase, a portion of the river section is scheduled to be excavated and refilled with suitable material. The “dry weather flow” is diverted through the other part of the river section or through a suitable diversion canal which connects the river section through spill tail canal. Coffer dams will be built up to protect the construction area from the river flow. Thereafter the other portion will be completed by following a similar method. 16. As measures of seepage control, a Silty Clay Cut off Trench is provided for the river section and Bentonite Slurry Wall for the rest of the dam. The Cut off Trench will be constructed on Slightly Weathered or Fresh Rock. High pressure cement slurry grouting will be injected to stop any possible seepage through rock fractures. The main dam will be constructed as a zoned dam with a centre core in the centre of the dam. The core will be constructed out of low permeable earth fill (Silty Clay). The 135 m long clear fall spill way with ogee section and 3/6.05 m X 4, 65 m Radial gated spill structure will be founded entirely on sound bedrock of high strength. 17. Existing cart track up to the bund road of the proposed dam will be improved and gravelled with carriageway width of 5 m. The access road will continue along the dam up 1. 425 km and connect to a by-road located downstream of the spill way and again join the bund road at 1.150 km. Contractor may construct temporary roads to burrow areas and to other required places during the construction phase with minimum disturbance to the forest.

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c. Construction activities related to resettlement sites

18. There are three temporary built houses within the 100 m buffer zone but no houses in the inundation area. An extent of 79 ha will be affected due to the inundation of the proposed reservoir and declaration of 100 m buffer zone. There are 107 affected persons in the farmer community. The Divisional Secretary of Vavuniya has already identified two locations as alternative lands for irrigated agriculture in the abandoned command areas of two abandoned minor irrigation reservoirs namely Katkulam reservoir in Puthukulam GN Division and Pandrikketakulam reservoir in Pandrikketakulam GN Division. In addition to this, investigation for identifying more alternative lands is also in progress. Since alternative lands are covered by jungle, it is required to obtain clearance from the Forest Conservation Department prior to allocating lands for agricultural practices. Figure 4 shows the downstream area for the identification of suitable areas for land to land compensation. d. Other construction activities

19. Large quantities of rock and soil will be generated in the dam construction. Preparation for foundations for permanent structures will be by excavating soil and rock as per engineering designs and site conditions. All boulders and rock that cannot be removed with excavating equipment will be blasted to manageable size and uase for rip rap protection. All unsuitable excavated material will be hauled to reinstatement of burrow pits or reused where suitable. Disposal material under main items of the engineering estimate is shown in Table 2.

Table 2 : Quantities of excavation requiring disposal

Structure Quantity in cu.m

Stripping topsoil in dam base and borrow areas 75,000

Toe Filter - Silty Clay 3,500

Cutoff trench – Silty Clay 10,500

Bentonite Slurry Cutoff wall – Bentonite/Soil mixture 1,500

Common Excavation in spill approach and spill tail canal 23,000

Common Excavation and soft rock excavation in spill foundation 6,500

18 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

Figure 4 : Potential areas for land to land compensation

20. Due to the construction of the bund, the existing gravel road has to be redone on the newly constructed bund. The existing Hindu Temple on the inner slope of the Periyakulam Bund also will have to be relocated at a higher elevation. There are no public or private buildings in the project area.

a. Material to be used

21. Total volume of excavation in Dam and Spillway is estimated to be 55,500 m3. Construction of the Dam involves 225,000 m3 of burrow earth and 22,000 m3 of sand including Sand Blanket and Chimney filters as per engineering estimate. The dam fill materials such as impervious soil material which meets the design standards, filter material suitable for the treatment plant, and other construction material such as sand, metal will be required. Soil material available in the reservoir bed will be used as much as possible after carrying out a burrow area investigation. Other materials will be transported from licensed quarries. The quantity of concrete in the works does not warrant establishing a concrete batching plant with cement silos. However a small Batching Plant or 21/15 or 16S construction mixers will be deployed, with cement being supplied in bag form.

19 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

5. Methodology of operation 22. Reservoir system will be operated and maintained by the NWS&DB. Regular maintenance of the reservoir head works such as bank erosion, pump houses, and transmission lines,repairs of the lifting pumps and submersible pumps, transmission & distribution lines will be the responsibility of NWSDB.

6. Workforce requirements 23. During the construction phase of the project, the required work force will be nearly 200 workers in different categories such as managers, engineers, technical officers, draft persons, quantity surveyors, supervisors, office assistants, accounting staff, machine operators, heavy & light equipment operators, carpenters, masons, bar benders, mechanics, electricians, drivers, nursery & planting workers, and other skilled, semi-skilled& un-skilled workers. During the maintenance phase, the work force will be not more than 15 including pump operators, treatment plant staff, technical officers and security personal. 24. Arrangements shall be made to educate and provide necessary training to employees, occupiers, workers or any other person requiring knowledge and training in occupational safety and health and related subjects either in collaboration with any other institution or university in Sri Lanka. On completion of such education or training, it is necessary to provide advisory services to contractor’s staff on the correct use of equipment, hazardous substances, physical, chemical or biological agents or products or any other hazards.

7. Phased implementation plan of the project 25. The tentatative construction schedule of Per Aru Earthen Dam and Spillway is shown in Table 3.

8. Total project cost, investment and funding sources 26. Total estimated cost of the Per Aru Dam Project is Rs. 616 million (US$ 5.5 Million) and funding is from ADB and surface water Development in through Grant Aid.

20 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

Table 3 : Construction schedule for Per Aru reservoir

21 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir B. Evaluation of alternatives

1. No action alternative 27. The ‘no action alternative’ is considered here under the scenario that the Per Aru Project would not be undertaken. Water for the existing pipe borne water supply scheme in Vavuniya comes from 11 ground water wells, of which only 8 can be operated presently due to shortage of pumps. Owing to the scarcity of water, the water is available only for 3-4 hours per day and the overhead reservoir can be filled partly once per day with about 400 cum/day of treated water. 28. The wells of the existing water supply system are mainly within the urban area therefore will be vulnerable to pollution from sewage and contaminants. The ground water too is of poor quality, having high levels of calcium, magnesium etc. contributing to hardness and subsequently leading to diseases. Already the number of cases with Chronic Renal Failure is increasing in Vavuniya. Without the introduction of surface water, the water supply situation will be 1500 cum/day whilst the projected demand for water in the urban area in 2030 is 12,000 cum/day. With the water demanding urban population is expected to increase to 76,701 persons, it would be impossible to meet the expectations. Therefore the aspirations of the Uthuru Wasanthaya, the massive development program in the North, which aims at resettling displaced persons in their own villages and creating a sound quality of life, will be able to meet, without provision of safe drinking water. This will also be contrary to the Millennium Development Goals and National Drinking Water Policy. On the positive side, 250.5 ha of land comprising largely of forests (riverine forests, dry mixed evergreen forests and shrub forests), some paddy lands and upland cultivated lands will be saved from inundation.

2. Site alternatives 29. In order to develop surface water resources, several options were considered at the pre-feasibility stage (ref. Small Town and Rural Arid Areas Water Supply and Sanitation Project - ADB TA 4853 – SRI conducted by Nippon Koei in association with IDP Consult Inc. in 2008). They are as follows;

a. Abstraction of water from Pawatkulam reservoir

30. Pawatkulam irrigation reservoir is the largest irrigation reservoir in the Vavuniya District. It lies about 11 km south west of the town. A supply from this potential source would require a pipeline about 15 km and a lift of about 58 m. However, this is exclusively used for irrigation with the present cropping intensity under the irrigation reservoir less than 1.0. Even with improved irrigation practices it may not be possible to increase the cropping intensity to 1.3. There is also no possibility of increasing the yield to the reservoir. The use of Pawatkulam Irrigation reservoir for public water supply may not be feasible and both the irrigation Department and farmers have objected to this. b. Abstraction of water from Irateperiyakulam and Vavuniya kulam reservoirs

31. The capacity of these irrigation reservoirs are too small compared to Pawatkulam reservoir. A similar cultivation pattern could be observed. In addition the Vavuniya reservoir receives sewage waste from the Vavuniya town area. As the cropping intensity is less than 1.0 and the storage available is small compared to Pawatkulam, further evaluation of this option was not conducted.

22 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

c. Pumping water from Tekkam anicut

32. The Tekkam Anicut (Anicut - Diversion Weir) across Malwathu Oya (Oya - Perennial Stream) located in the west of Vavuniya town, presently diverts water to Giants Reservoir on the right bank and Akathimuruppu irrigation reservoir on the left bank via diversion canals. The sill level of the Tekkam Anicut at this location is 19.00 m MSL. The existing tower level of the Vavuniya water supply scheme is 123.5 m MSL and is about 35 km from the Tekkam Anicut. Thus the lift of water from Tekkam Anicut to water tower is about 104 meters. The high lift, long distance and limited water during the dry months will hamper the use of water in the Malwathu Oya at Tekkam, as a source of water for Vavuniya Town. 33. Despite the fact that there is sufficient water during the months of October to January and that water normally flows over the Tekkam Anicut during the dry periods of the year, all water in the Malwathu Oya is diverted to both Giant’s irrigation reservoir and Akthimuruppu irrigation reservoir. The water available during this period is not sufficient to meet the agriculture demand in the command areas of the above-mentioned reservoirs. As such it is not possible to extract the water at Tekkam Anicut during this period for meeting the drinking water requirement of Vavuniya town. Further there is hardly any additional storage available to store water during the wet period of October to January

3. Design alternatives 34. Another feasibility study was carried to explore the available surface water resources of Per Aru. Hydrological model studies were carried out by using daily rainfall data from 1979 to 2010 (31 years) to assess the surface runoff from the catchment area at the proposed location of the dam. Feasibility of 04 optional models was tested. Table 4 shows the details of the design alternatives used in this connection.

Table 4 : The design alternatives with affecting lands

Alternative Demand Capacity FSL Area of Area of agricultural lands Designs (m3/day) (MCM) (m) inundation and forest land that MSL (ha) would be inundated Highland Paddy Forest (ha) land land (ha) (ha) 1 12,000 4.621 71.80 288.8 33.8 86.9 152.0 15,000 5.969 72.25 367.3 38.8 127.3 168.7 2 12,000 4.644 71.50 262.8 28.6 67.8 156.7 15,000 6.107 72.00 322.5 32.4 87.3 179.1 3 12,000 4.938 71.50 277.8 30.0 68.8 161.2 15,000 6.452 72.00 333.0 33.8 88.4 183.8 4 12,000 5.143 71.50 278.8 30.0 68.8 166.4 15,000 6.691 72.00 340.5 33.8 88.4 189.0

35. With a view to striking a balance between the area inundated by the reservoir and the water storage capacity even at the same contour, for example 72 m MSL or 71.80 m MSL or 71.50 m MSL, the shape of the dam was changed to minimize the inundation while maximizing the capacity. Subsequently, with the scope of minimizing the inundated area of the reservoir while fulfilling the demand of 12,000 cum/day, three full supply levels were tried as shown in Table 5.

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Table 5 : The options of dam and the land use

Demand Water Capacity FSL Area of Area of agricultural lands (cum/day) Supply (MCM) (m) inundation and forest land that would (cum/day) (ha) be inundated

Paddy Highlands Forest (ha) (ha) (ha)

12,000 2050 2.76 70.50 198.0 32.0 16.0 150.0

12,000 3925 3.31 70.75 218.0 42.5 16.5 159.0

12,000 6700 3.85 71.00 238.7 33.1 10.4 183.2

36. Striking at the best compromise, the dam design at the 71 m FSL was selected for the project. The bed rock of the designed location of the spillway was exposed to a length of more than 100 m. Therefore foundation condition was very much favourable for the radial gated concrete spill way with 03 radial gates of 6 m x 4.35 m. A comprehensive study has been carried out to assess instream flow needed to sustain the ecosystem functions that native fish and wildlife species depend upon to survive and flourish. By considering hydrological conditions, engineering design requirements, social needs and ecological sustainability 71m FSLfor the project was found feasible.

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25 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

III. DESCRIPTION OF THE EXISTING ENVIRONMENT

A. Topography and the study area 1. In a nutshell the proposed project envisages extraction of surface water from an impounding reservoir created by construction of dam acrossa river named Per Aru for the purpose of providing safe drinking water to residents of Vavuniya town in the Northern Province of Sri Lanka. 2. Vavuniya District falls within the Dry Zone of Sri Lanka where tropical dry climate is prevalent. The area covered by the District receives somewhat low rainfall throughout the year. The annual rainfall in the District varies from 650mm – 1100mm, and experiences heavy rains from October to December during Noth East monsoonal season. In comparison, the amount of rainfall received during the rest of the months is considerably low. The highest average monthly temperature (36°C), is recorded in the months of June, July and August while the lowest(29°C) is experienced in the months of January and December. The mean annual temperature is about 34°C. 3. Physiographically the area covered by Vavuniya District belongs to lowest peneplain of Sri Lanka. Generally, the area comprises of flat terrain with small scattered hillocks. The topography becomes more pronounced in South Eastern sector of the district while a flat terrain is identified in rest of the area. Madukanda, Thammannakanda and Velikanda are the prominent strike ridge structures identified within the South Eastern sector, representing higher elevations in the district. Major river systems are absent within Vavuniya District. However, a number of small to medium scale streams flows through the district and all of them are seasonal streams, which are active only during NE monsoonal rainy periods. Kanakarayan Aru, Chamali Aru, Kiul Aru, Chamalankulam Aru, Per Aru, Kal Aru and parts of Malwathu Oya are the main river systems flowing through the district. These river systems show a remarkable variability in discharge during dry and wet seasons 4. The river in question in this proposal is Per Aru, across which an earthern bund will be constructed to form a reservoir,for the purpose of providing drinking water to the Vavuniya urban areas. The river originates as a tributary of Parangi Aru in the north of the Vavuniya Town. At Palaimodai, it joins Turumpamoddai Aru, after which it is called Manal or Paranki Aru. Another river called Periyakatte Aru joins the Paranki Aru further downstream and finally discharges into the Indian Ocean about 35 km north east of Mannar. 5. Land areas are classified by Forest Conservation Department (FCD) and Survey Department for different purposes. Land areas classified by the FCD within the Vavunia district is shown in Figure 5. According to FCD, the forest cover within the catchment area falls under the categories of dry monsoon forest, open & sparse forest, shrub jungle, and non forest as shown in Figure 6. Within the non forest area of FCD map, there exist land cover /land use types classified by the Survey Department (SD) using topographical map of 1:50,000. They are scrub jungle, garden, paddy, water bodies and grasslands. The composite land cover classification map is shown in Figure 7. The “non forest” classified for grasslands was selected for afforestation. The suitable areas for afforestation of the project was selected by considering areas adjoining to the existing forest cover types which were similar to the affected forest cover types inside the inundated area. For the afforestation of riverine type, river banks of two streams which joint to the Per Aru at the upstream were selected within the residual area. 6. The boundaries of the study area is shown in Figure 6 and sample study area of the biotic survey is shown in Figure 8. .The catchment area consist of dry monsoon forest, open sparse forest, shrubs, riverine forest, scrub, paddy (agricultural lands), chena (perrenialcrop

26 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir cultivation), chena cultivations, gardens, and water bodies (streams, minor irrigation reservoirs and water logged areas). Some of the minor irrigation reservoirs are abandoned because of the past war situation.

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 5 : Proposed reservoir and forest classification in the Vavuniya District

28 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 6 : Forest cover within the upper catchment of the Per Aru

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 7 : Classified land cover/land use map of the catchment area

30 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 8 : Biotic study area and the inundation area

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir B. Physical Environment

1. Geology 7. Geologically this area belongs to the Precambrian Wanni complex which is characterised by thick sequences of ortho gneisses in northwest and western sections of the country. A substantial part of the Wanni Complex is made up of amphibolites facies rocks but areas adjacent to the Highland Complex comprise of granulite grade rocks which include both charnockites and meta pelites. These are pink granitic gneiss and biotitic gneiss and the latter includes hornblende gneiss, granodioritic, banded streaky and magmatic rocks. About 300-m downstream from the proposeddam, there is a 6 - 8m thick alluvium formation on either side of the river banks. This lies between Kaddiyarkulam and Velankulam Reservoirs. Shallow rock bands crossing the stream were detected during the resistivity surveys. Figure 9 shows the geology in the project area based on the geological map prepared by the Survey Department and relevant field information. Vertical Electrical Sounding (VES) tests were carried out to investigate geophysical characteristics of deep subsurface and the results of the VES on the project is shown in Figure 9.

Figure 9 : Geology of the study area

National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir

Table 6 : Summary of VES observations – Vavuniya

Area Over burden Depth of weathered Fractured thickness (m) rock (m) zones found (m)

Upstream (Thandikulam area) 0 – 6 6 – 10 12 – 28 Immediate upstream side of the Alluvium (0 – 4) 4 – 5 15 – 35 proposed Per Aru Reservoir Downstream side of the proposed Alluvium (0 – 6) 6 – 8 16 – 30 Per Aru Reservoir Source: Interim Report, Package C

2. Geotechnical condition 8. Geotechnical profile of the area was studied by investigating 52 bore holes along the proposed dam axis and 04 bore holesin the reservoir bed area. In the proposed location of the dam a fairly strong rock, quartzite, exists at the proposed crest overflow spillway site to support the structure. A fairly strong rock, Chernockite, exists in the stream bed along the new dam axis.Figure 10 shows the locations of the bore holes and the Geotechnical profile of 05 bore holes are shown in Figure 11.

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Figure 10 : Locations of bore holes and test locations of air quality

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 34

Figure 11 : Geotechnical condition of the dam

35 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir 9. The results of geotechnical investigations indicate that the ground conditions are fairly variable, probably due to the curved nature of the dam axis with respect to the direction of flow in the river. The general stratigraphy of the site consists of upper overburden soils formed due to weathering of the parent rock, which is mainly chernockite and granite. These rocks comprise around 50% feldspar mineral, 30 % quartz and 10 % of mica along with numerous other minerals. The feldspar mineral has broken down into clays whereas the quartz and mica remain unaltered since they are more resistant to weathering.

3. Leakage conditions 10. The geo-structural conditions in the Per Aru area do not indicate major lineaments or shears and therefore development secondary porosity is poor. It is assumed that tectonical activity has not taken place and pressure exerted on the rocks is very limited. Few major shear zones and lineaments were observed close to the Thandikulam area (In the upstream area of the proposed Per Aru dam). In most of places of the Per Aru catchment, deep fractures are not prominent. Weathered rock and fragmented rock which are associated with shears and lineaments are the major groundwater bearing zones.

4. Agro-ecological regions 11. The Per Aru basin falls in the DL 1 Agroecological Region, which is situated in the dry zone of the country as classified by the Department of Agriculture in 2004. In DL1 region mean annual rainfall is about 800 mm. Mean temperature is about 300C . The main soil groups are Reddish Brown Earth (RBE) and Low Humic Gley (LHG). Drainage classes are well drained to poorly drained. Rice is mainly grown in moderately to poorly drained soils. Dry zone of the country has been sub-divided in to 11 sub Agroecological Regions (AERs) and 03 AERs namely DL1b, DL1e, DL1f appear in the study area as shown in Figure 12 and the characteristics of sub regions are shown in Table 7.

Table 7 : The characteristics of sub regions

Climatic Agro- 75% Terrain Major Soil Group Land Use Zone Ecological expectancy region Value of Rainfall(mm) DL1b > 900 Undulating Reddish Brown Earth Rainfed upland & Low Humic Gley crops, Paddy soils. Scrub, Mixed home gardens, Forest

plantations. DL1e > 900 Undulating Reddish Brown Earth Rainfed upland & Low Humic Gley crops, Paddy soils. Scrub. DRY ZONE DRY ZONE Low Country DL1f > 800 Undulating Reddish Brown Earth Rainfed upland & Low Humic Gley & crops, Paddy Grumusol soils. Scrub, Natural forest.

36 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 12 : Agro Ecological Regions of the surrounding area

37 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir 5. Land suitability 12. Reddish Brown Earths (RBE) are the prominent soils in the dry zone. They have the characteristic reddish brown colour. Generally there is a layer of gravel. The texture may vary from sandy loam to sandy clay. Low Humic Gley Soils (LHG) occupies larger areas of the lowlands in the dry, wet, and intermediate zones. They have dark grey and grayish brown colours. Low Humic Gley Soils soils are poorly drained. Long periods of wetness have caused the iron and manganese in the soil to remain in a reduced state giving their characteristic dark grey and grayish brown colors. Calcium carbonate concretions occur at some depths. The soils are most suitable for intensive wetland paddy cultivation or irrigated paddy cultivation. The land form pattern of this region is mainly undulating and the slope varies from 2-8%. Rice growing LHG soils are confined to the valley bottoms of the undulating terrain where the slope ranges from 0-2%. 13. The topsoil is sandy loam or sandy clay loam while the sub soil is sandy clay loam or sandy clay. The soil type in the downstream river section is alluvial. This is a deep, poorly drained soil with dark brown to light grey surface soil. The texture of the surface soil is loamy sand. This soil is structureless and single grained. The colour of the sub surface soil ranges from dark grayish brown, light olive brown to olive gray. The texture of the subsurface soil varies from sandy loam to sandy clay loam. Clay content of the soil increases with increasing. 14. During Maha (Wet) season, all the rice lands are used for cultivation of paddy, but during Yala (Dry) season imperfectly to poorly drained soils can onlybe used for paddy cultivation under rainfed condition and moderately drain RBE soil needs fair amount of water as supplementary irrigation for a good rice crop. In RBE there is a layer of gravel which is a mixture of quartz, ironstone, iron manganese nodules and feldspar. Therefore, these moderately drained lands are suited for other field crops during Yala season. However, rainfed cultivation of rice in lowland in those regions is possible only during the major rainy season (Maha season) with limited irrigated water. When the Wet zone of Sri Lanka experiences Southwest monsoon rains, the same monsoonal wind blows over the Dry zone as a warm and dry wind. Hence, crop water requirement during this period, May to September (Dry season) is very much higher than that of the other times of the year (Wet season). Crops like onions, shallots and leafy vegetables are grown under irrigation with bedded basin systems to provide irrigation and drainage. Since the water holding capacity of RBE soils are moderate, deep rooted other field crops can be grown with high irrigation intervals. The infiltration rate of the RBE is about 25-mm per hour in cultivated soils (Mapa et al, 2010). Since most of the sub soils of RBE are rich in clay and the presence of a thick gravel layer, surface drainage should be adequately provided to prevent temporary water logging conditions especially for crops such as chilli, tomato, maize etc which are susceptible to soil saturation. In eroded areas addition of green manure can increase productivity of crops by increasing the content of organic matter.

6. Climate of the low country dry zone 15. The expected annual rainfall at 75% probability level in this region ranges from 650 to 1,100 mm depending on the agroecological region. As shown in Figure 13. there are number irrigation reservoirs constructed in this area to store the rainfall runoff and use it during the dry period. In some Agroecological Regions (AERs) monthly rainfall distribution depicts a bi-modal pattern where as AERs found in the northeastern and eastern parts of the Dry zone shows a uni-modal monthly rainfall distribution. The general wind speed of the Dry zone is 3- 5 km/hr. However, during said period, it may reach even 12 -15 km/hr. The average maximum temperature in the Dry zone ranges from 29 to 38 0C depending on the AER. The highest values are being recorded during the period of late February to late September irrespective of the

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir location. Thus, high temperature injuries are being experienced in rice grown during Yala season in the Dry zone. Continuous weather observations have shown that it is becoming a more and more common feature in rice cultivation during recent times and it could be a repercussion of global warming. The average minimum temperature ranges from 260 C to 290 C where the lowest values are generally observed during the period of December to February, a common phenomenon for the entire island. However, further low nighttime temperatures are experienced during winter months in the northern peninsula of the island due to the influence of the huge land mass of the Indian sub-continent making it possible to grow potato. However, rice is hardly grown in this region due to some other edaphic limitations. The day time relative humidity in the Dry zone is generally ranged from 50% to 75% whereas nighttime values may reach even up to 90%, especially during winter months of the year.

7. Mineral resources 16. The mineral resources map of the Northern Province is shown in Figure 14.There are no mineral resources within the project area or in close proximity of it that would be inundated by the proposed reservoir or its downstream river section. In the Upper catchment there are dune sand and mineral sand scattered over the area. In the downstream area dune sand and red bed plots are apparent.

39 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 13 : Existing water bodies and streams

40 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 14 : Mineral resources map of the Northern Province

41 National Water Supply and Drainagee Board EIA Study on Per Aru Reservoir

8. Rainfall 17. The average annual rainfall which is derived from the data obtained from the Meterrological Department for the period from 2000- 2009 is 1,420 mm. Most of the rainfall is experienced during NE monsoon (November – January) and the inter-monsoonal months of October and April. The months of February- March and May- September are generally dry. Average rainfall during NE monsoon, inter-monsoonal months of October and April are 615 mm, 239 mm and 121 mm respectively. PerAru catchment received over 2,000 mm annual rainfall in 1963, 1972 and 1984. The monthly rainfall over 450 mm was observed in several occasions during last 50 years as 495 mm in Oct 2007, 623 mm in Feb 1984, 601 mm in Dec 1983, 483 mm in Nov 1979, 556 mm in Dec 1973, 484 mm Oct 1969, 459 mm in Dec 1967and 584 mm in Nov 1963. The mean monthly rainfall distribution for Vavuniya is shown in Figure 15. Slight reduction in maha rainfalls and an increase in yala rainfalls during recent past indicates the need to perform trend analysis for estimating the inflow levels to projected year 2025. The 50%, 75%, 80% and 90% probability rainfalls for Vavuniya are given in Table 8. Rainfalls at 75 % probability were considered for safe storage calculations and rainfalls at 50% probability were used to calculate for alternative use of groundwater in the water supply scheme.

Figure 15 : Mean monthly rainfall distribution in Vavuniya

42 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Table 8 : Monthly rainfall at different probability levels

Probability Rainfall (mm) Month 50% 75% 80% 90%

Jan 76.4 13 7.6 2.2 Feb 57.9 6 0.2 0

Mar 56.3 17 14.0 7.6

Apr 130.4 94 81.6 66.2

May 73.1 48 23.4 18.6

Jun 13.4 0 0 0

Jul 45.5 4 1.4 0

Aug 67.2 15 8.0 0.2

Sep 97.5 46 33.4 15.2

Oct 231.4 143 116.4 101.6

Nov 271.4 182 157.6 140.2

Dec 246.0 133 115.2 90.2 Total 1,366.50 701 558.8 442

Source: M. Thuraisingham, Pacakge C, NWSDB

9. Temperature 18. The monthly temperature for the Vavuniya varies between 26⁰ C – 34⁰ C.

10. Evaporation 19. Mean monthly evaporation distribution for the Vavuniya is given in the Figure 16. Minimum and maximum monthly evaporation measured at the Vavuniya meteorology station are 32.4 mm in Nov 2003 and 186.3 Sep 2002 respectively.

43 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 16 : Mean monthly evaporation distribution at Vavuniya from 2001 to 2008

11. Hydrology

a. General description of the catchment area

20. The Parangi Aru originates in the Vavuniya District, north of the town of Vavuniya as PerAru in the North Western direction. At Palaimodai the Turumpamoddai Aru joins the river on right side, afterwards this river is referred to as Manal or Paranki Aru and further downstream of the Paranki Aru, the Periyakatte Aru enters the Paranki Aru from the left side. Finally this river discharges into the Indian Ocean about 35-km North-East of Mannar. The PerAru crosses the A-9 road at Nochchimoddai. Paranki Aru crosses the A-32 road at 37thkm, and its branch crosses it at 34thkm at Illupaikkadavai. The river basin has an elongated form with a length of 70-km and the width ranges from 10-m to 20-m. The Catchment of the Parangi Aru is located in the Northern dry zone and its area is 832-km2. As per the design report of Per Aru reservoir, average discharge volume to sea is 312-MCM per year (Hydrological Studies for the Per Aru Reservoir in Vavuniya, 2011). The catchment of the Parangi Aru is bounded by the basins of the Pali Aru and Chamalakulam Aru in the north, the Kanagararayan Aru and Ma Oya in the east and the Kal Aru, a tributary of the Malwathu Oya, and Nay Aru in the south. The banks and beds of river normally consist of unconsolidated sandy to silt material with some outcrops or boulders of hard rock. 21. Water to the proposed reservoir flows from two main streams located in the Per Aru upper catchment. The upper catchment hast wo medium reservoirs and numerous minor reservoirs. The northern stream within the catchment has the water released from Mamaduwa reservoir together with the catchment runoff from the northern area between Mamaduwa reservoir and proposed reservoir. The southern stream within the catchment has the water released from Vavuniya reservoir passing two minor reservoirs before entering the proposed reservoir. The flow includes the run-off from the southern catchment between Vavuniya reservoir and the proposed reservoir. 22. The landscape of sub catchment is quite flat with an altitude ranging from 150-m to 65- m. The total catchment area and effective catchment area of the proposed reservoir are 185- km2 and 42-km2 respectively.The northern part of the catchment is covered with a dense forest. With the construction of the dam across the river, a reservoir will be built and the water spread area will extend up to 71.0 m contour elevation at the full supply level.

44 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

b. Flow details including mean annual flow, average flow, annual variation of the flow in the river

23. Weekly average stream flow had been computed for the period December 2008 to December 2010 at the dam site. Table 9 shows the average,monthly values for the above period.

Table 9 : Monthly average stream flow from Dec. 2008 to Dec. 2010 (m3 /sec)

Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Aver 2008 11.29 2009 2.97 0.2 0.25 0.12 0.01 0.01 0.00 0.14 0.15 0.00 0.12 18.0 1.83 2010 1.08 0.03 5.48 0.88 0.48 0.06 0.01 0.00 0.06 0.12 4.84 14.91 2.33 Source: Hydrological Studies for the Per Aru Reservoir in Vavuniya conducted by the ADB5 Project, 2011.

c. Discharge

24. The gauging station has been in operation at proposed dam axis from December 07, 2008. Water levels are measured in the morning and the evening using two 2.4-m gauge posts installed at 65-m MSL and 67.4-m MSL. Observed water level at gauging station during morning and evening are given in Figure 17 and Figure 18. Highest water level was observed during December and lowest water level during July and August.The lowest water level recorded is mentioned as zero at several days due to the guage position.However, thefield observation shows that the river is experiencing very low flow at the end of July 2011 in the range of 40 l/s to 20 l/s. The last few days of the long dry spell showed absolutely no flow in mid August 2011 at the proposed dam site.

Figure 17 : Water level at gauging station (morning)

45 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 18 : Water level at gauging station (evening)

25. The morning and evening flow was calculated using morning and evening water levels at the gauging station and elevation - discharge relationship is shown in Table 10.

Table 10 : Elevation - discharge relationship

Elevation m at MSL 65.25 65.59 65.94 66.00 66.38 67.18 68.00

Discharge (m3/sec) 0.0 2.3 4.6 4.8 21.5 105.0 367.0

26. As the rainfall data are available from 1979 the stream flow at the weir site was simulated for better predictions. Table 11 shows the monthly generated inflow at the dam site from 1979 to 2010.

46 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Table 11 : Monthly In generated In flow (MCM) at dam site

Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total 1979 0.625 0.053 0.518 0.313 0.063 0.026 0.026 0.010 0.926 0.786 8.092 8.357 19.794 1980 1.685 1.021 0.086 0.301 0.059 0.026 0.026 0.000 0.152 0.663 2.085 4.507 10.611 1981 1.450 0.657 0.129 0.231 0.084 0.026 0.026 0.035 0.693 1.070 1.315 4.315 10.029 1982 0.608 0.460 0.088 0.275 0.124 0.026 0.026 0.000 0.130 0.421 2.330 8.015 12.501 1983 0.554 0.318 0.069 0.158 0.199 0.021 0.026 0.023 0.126 0.802 3.147 20.625 26.067 1984 4.139 0.279 5.410 0.394 0.077 0.026 0.026 0.000 0.110 0.296 3.924 3.037 17.718 1985 1.899 0.247 0.447 0.280 0.145 0.026 0.026 0.000 0.063 0.525 5.054 10.411 19.122 1986 3.837 0.246 1.457 0.177 0.063 0.026 0.026 0.045 0.000 1.256 2.051 2.004 11.189 1987 1.358 0.244 1.122 0.279 0.137 0.026 0.026 0.000 0.208 1.617 1.854 0.506 7.376 1988 0.886 0.219 0.351 0.392 0.074 0.026 0.026 0.099 0.352 0.000 0.380 0.210 3.016 1989 1.001 0.199 0.597 0.252 0.101 0.026 0.021 0.000 0.156 0.494 2.204 2.048 7.097 1990 2.689 0.180 1.192 0.173 0.137 0.026 0.026 0.000 0.000 0.000 0.000 0.000 4.423 1992 0.623 0.156 0.086 0.126 0.007 0.026 0.026 0.014 0.135 0.038 4.316 3.347 8.899 1993 0.806 0.137 0.437 0.283 0.048 0.026 0.032 0.038 0.193 1.086 4.489 21.322 28.897 1994 2.495 0.135 1.934 0.300 0.027 0.032 0.026 0.000 0.199 1.084 3.041 2.247 11.520 1995 3.205 0.117 0.109 0.360 0.179 0.026 0.026 0.094 0.000 0.508 3.417 0.765 8.806 1996 0.844 0.113 0.406 0.589 0.086 0.026 0.032 0.221 0.110 0.752 1.694 10.953 15.825 1997 1.183 0.102 0.110 0.392 0.181 0.032 0.026 0.063 0.192 0.300 8.372 10.941 21.896 1998 2.419 0.100 0.777 0.187 0.212 0.026 0.026 0.110 0.000 0.042 3.535 6.337 13.773 1999 7.833 0.085 0.188 0.470 0.134 0.026 0.026 0.000 0.000 1.604 2.007 9.196 21.570 2000 2.753 0.082 3.024 0.187 0.024 0.026 0.032 0.226 0.007 0.478 3.973 5.174 15.988 2001 7.211 0.080 0.087 0.468 0.100 0.026 0.032 0.059 0.320 0.797 1.418 7.188 17.788 2002 2.505 0.077 0.111 0.394 0.140 0.026 0.026 0.000 0.033 0.894 4.428 6.324 14.956 2003 2.501 0.060 0.338 0.253 0.162 0.026 0.026 0.086 0.140 0.532 4.397 7.164 15.684 2004 0.839 0.059 0.620 0.309 0.261 0.026 0.026 0.047 0.173 0.738 3.429 8.747 15.273 2005 3.381 0.059 0.171 0.383 0.082 0.026 0.026 0.166 0.034 0.494 5.677 2.918 13.418 2006 2.119 0.059 1.338 0.411 0.038 0.026 0.032 0.000 0.268 0.790 3.345 2.964 11.391 2007 0.585 0.052 0.572 0.197 0.032 0.026 0.026 0.021 0.355 2.034 0.467 9.076 13.443 2008 1.181 0.043 0.482 0.288 0.048 0.026 0.026 0.066 0.244 0.630 3.038 11.867 17.940 2009 1.064 0.032 0.690 0.262 0.053 0.026 0.026 0.496 0.105 0.772 3.597 6.600 13.724 2010 5.321 0.154 0.090 0.299 0.124 0.026 0.026 0.026 0.023 0.450 4.013 15.052 25.604

Source: Hydrological Studies for the Per Aru Reservoir in Vavuniya conducted by the ADB5 Project, 2011.

d. Probability inflow

27. The probability inflow to the proposed reservoir was computed on monthly basis by incorporating inflow due to effective rainfall in the hydro-catchment, catchment Inflow, and the inflow by spilling of irrigation reservoir in the hydro-catchment and drainage water flowing from the command areas in the hydro-catchment. The computed probability inflow to the proposed reservoir is given in Table 12.

47 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Table 12 : Probability inflow

Probability Inflow (MCM) 75% 50% 90% Jan 0.220 0.464 0.220 Feb 0.180 0.330 0.180 Mar 0.040 0.164 0.040 Apr 0.342 0.486 0.232 May 0.144 0.214 0.080 Jun 0.072 0.072 0.072 Jul 0.056 0.097 0.056 Aug 0.020 0.104 0.020 Sep 0.058 0.202 0.000 Oct 0.488 0.839 0.324 Nov 1.747 2.490 1.400 Dec 2.313 4.273 1.571 Total 5.68 9.735 4.195

Source: Thuraisingham, 2011, Interim Report on Hydrology of Vavuniya and Manner, Package C

e. Minimum dry season flow

28. As an average, from June to August the river shows a vey low flow (Ref. Table 9). The minimum flow for the years 1979 to 2010 is shown in Figure 19. According to the Figure, in general, the stream flow shows a minimum during the months June, July and August.

Min monthly flow (cum/sec) 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Figure 19 : The varaition of the minimum flow between the most dry months of the year

48 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

29. Table 13 shows the probability levels of dry season flow in River

Table 13 : The probability levels of dry season flow in River

50% probability 75% probability 95% probability

Dry season flow (cum/sec) 0.01 0.04 0.04

f. Base flow

30. The field observation shows that the river is experiencing very low flow at end of July 2011 in the range of 40 l/s to 20 l/s. The last few days of the long dry spell showed absolutely no flow in mid August 2011 at the proposed dam site.

g. High flood pattern of the project area

31. The flood hydrograph at the damsite for a 100 year return period is shown in Figure 20.

Figure 20 : The flood hydrograph of 100 year return period

32. Flooding occurs during the Maha rains, especially in the month of December. The peak flood return periods 100, 50, 25 and 10 are 22,000 cuft/s, 18,779 cuft/s.16,393 cuft/s,13,940 cuft/s respectively. 33. Table 14 shows the main hydrological features of the dam.

49 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Table 14 : Main hydrological parameters of proposed dam

Project Feature Unit Value Catchment area km2 42.00 Mean annual flow at dam site MCM 14.19 Mean flow at dam site m3/s 0.45 1:100 year flood peak discharge m3/s 623.00 1:50 year flood peak discharge m3/s 531.76 1:25year flood peak discharge m3/s 464.19 1:10 year flood peak discharge m3/s 394.73 Net evaporation loss from reservoir MCM 2.84 Seepage Loss MCM 0.27

h. Existing water use pattern of the project area

34. The Parangi Aru originates in the Vavuniya District, North of the town of Vavuniya in the North Western direction. Its immediate catchment goes upto the Mamaduwa reservoir which is a medium irrigation reservoir. The river is not tapped for any irrigation scheme before, at or after the site of proposed dam. It supports a riverine forest vegetation on either side of the river all the way upto the point of its discharge to the sea. The waters of the river are sometimes tapped illegally for paddy and other field crop cultivation downstream of the proposed dam. 35. The Figure 21 shows the longitudinal section of the river reach.

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 50

Figure 21 : A longitudinal section of the river reach

51 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

i. Surface water quality

36. The water quality of the Per Aru river is shown in Table 35 while the Sri Lankan standards for potable water is shown in Table 15.

Table 15 : Water quality measured in 2011 of River (Average)

SLS Standard for Parameter Value Unit Observation drinking water Colour 70 Pt Co. 30-May Above allowable limit Turbidity 6.49 NTU 08-Feb Within the maximum permissible level pH 8.52 7-8.5 Above allowable limit EC 393 Us/cm 750safe Chloride 36 mg/l 200 safe Alkalinity 32 mg/l 200 safe

NH3 0.39 mg/l 0.06 Above allowable limit

NO3 nil mg/l 10 safe Fl 0.2 mg/l 0.6-1.5 safe Total Phosphates nil mg/l safe TDS 175 mg/l 500 safe Total Hardness 152 mg/l 250-2000 safe Total Iron 1094 mg/l 250-600 Above allowable limit

SO4 nil 0.3-1.0 safe Mg nil 100-240safe Source: Piyasiri (2011) Catchment Management Plan Report 7, ADB Package C, NIRAS and RDC Consultants

12. Groundwater 37. On either side of the River there is alluvium formation. The extent of the alluvium formation and associated fractured zones or favourable lithological boundary zones, indicates that a considerable amount of ground water could be obtained. However, yield testing had not been performed. Types of aquifers and ground water quantity and salinity levels are shown in Figure 22, Figure 23 and Figure 24.

52 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 22 : Types of aquifers within the reservoir area

53 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 23 : Ground water quantity map of the reservoir area

54 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 24 : Salinity concentration of the ground water at the reservoir area

55 National Water Supply and Drainage Board EIA Study on Per Aru Reservo

a. Groundwater availability and recharge

38. Vertical electrical sounding testswere carried out in downstream areas of the proposed Per Aru dam for making indirect observations of the sub surface and consequently eight test tube wells were constructed to identify soil characteristics, groundwater quality and water table fluctuations. There is no hydraulic continuity through subsurface soil strata and limited localized pockets in some places of the area. Thickness of sand formation varies from place to place and generally it lies in between 1 – 3 m. Excess iron, manganese hardness and alkalinity are major water quality issues in the shallow aquifer of this area. Groundwater table lies 2.0 – 4.5 m below the ground surface and it varies with the monsoonal rains and drought. Soil and weathered rock formations and flushing yield of the test tube wells indicate that the porosity and permeability of overburden soil is fairly satisfactory for large scale development of shallow groundwater. Investigations carried out for the preparation of the design report of proposed reservoir, indicate that storage and recharge capacities are satisfactory for development of potential aquifers as the porosity and permeability of soil and weathered rock strata are fairly high. Further, the underground geological formations have formed natural barriers and consequently shallow aquifers get fully saturated with catchment water. 39. Alluvial deposits were encountered near the river banks spreading over 75 -100-m along the width of the river where the valley is flatter. An outcrop of fairly strong metamorphic rock, quartzite, was encountered in few places. The following general conclusions have been drawn from the results of the geotechnical investigations. • The overburden on the right side of river is predominantly residual in nature, probably due to higher ground levels; • A fairly impervious silty clay residual soil layer of more than 1-m thickness was observed in almost all the bore holes. This layer of impervious material is likely to minimize seepage losses from the reservoir and it is anticipated that the reservoir will be fairly water tight; • The Lugeon permeability tests conducted in the rock indicate that the slightly weathered to fresh rock is water tight and even the moderately weathered rock has low permeability. Due to presence of a more than 1-m thick cover of silty clay all over the project area and provision of deep cutoff trench (where required), the grouting of bed rock is not required. 40. According to the resistivity surveys, 6-8m thick alluvium cover exists in the downstream area of the proposed Per Aru dam. Rock bands are extended across the stream and between these rock banks underground water reservoirs exist. Alluvial and regolith aquifers mainly refresh with monsoonal rains, Reservoirs and flooded water of the Per Aru river. Top soil layers consist of clay rich formations and due to the that direct infiltration is limited. Flat topographical conditions and north south directed rock bands, restrict the groundwater flow velocity and therefore in some areas flow is almost nil. This may lead to increasing the accumulation of minerals in groundwater aquifers. With the increase of the water head in upstream area of the Per Aru river, it will help to enhance the water retention period in soil strata and recharge capacity of the groundwater aquifers. The groundwater sources in the downstream area of the proposed dam are underutilized. Extraction of groundwater from this area will help to flush off formation and subsequently water quality will be improved (Interim Report of the ADB5 Package C, 2011)

56 National Water Supply and Drainage Board EIA Study on Per Aru Reservo

b. Ground water quality

41. The water quality in the ground water in Vavuniya is shown in the Figure 25.

57 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Max. desirable level = 250

Max. permissible level = 600

a. The mean conductivity values of Vavuniya b. Mean Fluoride values in Vavuniya c. Mean hardness in the waters of Vavuniya from 1992 to 2010 (NWSDB) from 1992 to 2010 (NWSDB) from 1992 to 2010 (NWSDB)

d. Nitrate and phosphate level fluctuations in the waters in Vavuniya e. Total hardness and conductivity fluctuations in Vavuniya f. Fluoride and total hardness fluctuations in the waters in Vavuniya from 2009 to 2010 (NWSDB) from 2009 to 2010 (NWSDB) from 2009 to 2010

Figure 25 : The water quality in the ground water in Vavuniya

58 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

13. Land use

a. Existing land use pattern of the Per Aru catchment area

42. The existing land use/land cover patternswithin the catchment area including, inundated area and sample study area were extracted from the forest classification map of the Forest Conservation Department (FCD) and the 1:50,000 topographical map of the Survey Department and they are shown in Figure 26. The existing land use/ land cover types comprise dry monsoon forest, open sparse forest and shrub, paddy (agricultural) lands, Chena (perrenial crop cultivation), garden, irrigation reservoirs, and other water bodies including streams. The area close to the Vavuniya Town is residential and commercial.Thereby land use is classified as garden and other commercial infrastructure. In the downstream river segment, the land use is primarily dry monsoon forest, scrub and non forest. The landuse/land cover types and extents extracted from the maps are shown in Table 16.

Table 16 : Land use/land cover pattern of the catchment area

Land cover/ Land use Extent (ha) % Classification authority

Dry Monsoon Forest 7521 30.1 Forest Conservation Department

Open and Sparse Forest 2248 9.0 Forest Conservation Department

Shrub 875 3.5 Forest Conservation Department

Non Forest 3009 12.1 Forest Conservation Department

Scrub 2152 8.6 Survey General's Department

Garden 2440 9.8 Survey General's Department

Paddy 3852 15.4 Survey General's Department

Chena 1080 4.3 Survey General's Department

Water bodies 1707 6.9 Survey General's Department

Roads 51 0.2 Survey General's Department

Rock 15 0.1 Survey General's Department

Total 24950

43. The land use/ land cover pattern in the inundation area including the 100-m buffer zone is shown in Figure 27 and the extents in Table 17.

59 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 26 : Land use/land cover of the catchment area

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 27 : Land use/ land cover of the inundation area and the 100 m buffer zone

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir Table 17 : The land use of the inundation area and 100m buffer zone

Reservoir 100 m buffer zone Total extent of land Forest Classification inundation area of the reservoir cover and land use Extend (ha) % Extend (ha) % Extend (ha) % Dry Monsoon Forest 146.0 58.0 45.0 53 191 57 Open Sparse Forest 18.0 7.0 5.0 6 23 7 Scrub 4.0 1.5 10.0 12 14 4 Non Forest 21.0 8.0 4.0 5 25 7 Paddy 60.0 24.0 19.0 23 79 24 Water Bodies 1.5 0.5 0.5 1 21 Total 250.5 83.5100 334 100

b. The land use potential of the area & zone

44. Due to the 30year war, some of the cultivated lands had been abandoned and subsequently turned to jungle. However, due to the culmination of the war, people are returning to their original land and also many are being resettled in new areas which had hitherto been a forest land use. In order to facilitate sustainable development while conserving the important ecosystems, an Integrated Strategic Environmental Assessment has been done on the Northern Province by the Central Environmental Authority with 25 other agencies who have a stake in development of the Northern Province. This exercise was coordinated and funded by UNDP. Figure 28 shows the map of areas with potential for development in the Nothern Province including Vavuniya District.

62 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 28 : Land use development potentials of the area

63 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir 14. Air quality and noise

a. Air quality

45. There is no serious air pollution in the study area. It was proven through the air quality measurements obtained at existing places of important human activity and the proposed construction activity sites. Testing was carried out during 18-21 October, 2011 from 16.00 hrs to 13.00 hrs next day. 46. Air stressor measurements including Suspended Particulate Matter (SPM), Particualte Matter less than 10 micro grammes (PM 10 ), SO 2 , NO2, obtained as a 24 hour average and CO, CO2 obtained from one hour samples at the 3 locations identified in the project area and environs are shown in the Table 18 and Table 19. 47. According to the field air quality measurements the pollutant contents measured are well below the permissible ambient air quality levels stipulated by the Central Environmental Authority.

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 64

Table 18 : Air quality data obtained in October, 2011

Parameter Concentration (micro g/m3) GPS positions of CEA max CEA max CEA max CEA max sampling locations permissible PM permissible permissible permissible SPM level 10 level SO2 level NO2 level 401153.17 mN 51 300 12 100 11 80 <10 100 165720.97 mE 401634.88 mN 26 300 6 100 <10 80 <10 100 164911.33 mE 402196.58 mN 27 300 10 100 <10 80 <10 100 164158.48 mE

Source: ITI Report No. SS 1113385 on Air Quality Assessment (2011)

65 National Water Supply and Drainage Board EIA Study on Per Aru Reserv

48. Table 19 shows the measurements of C02 and CO in sampling locations

Table 19 : The measurements of C02 and CO in sampling locations

0 GPS Time C02 (ppm) CO (ppm) RH (%) DBT ( C)

1 401153.17 mN 9.00 – 10.00 415 0 78.6 30.2 165720.97 mE 10.00-11.00 372 0 72.0 30.8 11.00-12.00 350 0 67.3 31.6 12.00-13.00 388 0 67.8 30.6 13.00-14.00 351 0 64.7 30.8 14.00-15.00 353 0 64.7 30.8 15.00-16.00 353 0 62.0 30.1 16.00-17.00 375 0 81.4 27.0 2 401634.88 mN 9.00 – 10.00 415 0 77.2 30.7 164911.33 mE 10.00-11.00 405 0 63.5 31.0 11.00-12.00 406 0 57.0 33.0 12.00-13.00 405 0 63.1 33.3 13.00-14.00 381 0 68.5 32.6 14.00-15.00 361 0 60.7 32.1 15.00-16.00 385 0 65.1 30.2 16.00-17.00 420 0 76.2 28.0 3 402196.58 mN 9.00-10.00 417 0 68.3 30.1 164158.48 mE 10.00-11.00 418 0 60.2 30.7 11.00-12.00 409 0 62.6 32.4 12.00-13.00 389 0 64.8 32.8 13.00-14.00 380 0 63.7 32.0 14.00-15.00 372 0 60.3 30.9 15.00-16.00 387 0 61.5 30.6 16.00-17.00 365 0 83.0 25.9

b. Baseline information on noise/vibration quality

66 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

49. The proposed site is located in a very quiet area. The residential areas are located far away from the site. There is no predominant existing noise sources in the vicinity of the proposed site. As the land is within a Pradeshiya Sabha area, which is predominantly rural, the surrounding area can be considered as ‘Low noise’ area according to the Gazette Notification No. 924/12 of 1996 on noise pollution control. The noise and vibrations were recorded in four locations of the project area. Two hour measurements were taken at each location between 10.00 to 18.00 hrs during the day time while one hour measurements were taken between 19.00 to 21.00 hrs during the night time. 50. At present there is no evidence of any irritating noises in the project area and environs. Feedback obtained from the people through discussions and interviews gives an idea about the absence of irritating noise condition in the area. Noise and vibration measurements obtained at existing important places of human activity and the proposed construction activity sites are given in the Table 20 Field observations were conducted by the Industrial Technology Institute (ITI). Testing was carried out during 18-21 October, 2011 from 16.00 hrs to 13.00 hrs next day.

Table 20 : Noise measurements in project locations

GPS Locations Noise Level Day Time Night Time ENL dB(A) RBL dB (A) ENL dB(A) RBL dB (A) 1 401153.17 mN 38 34 43 39 165720.97 mE 2 401634.88 mN 41 36 43 40 164911.33 mE 3 402196.58 mN 46 42 43 42 164158.48 mE 4 402465.09 mN 33 32 37 33 166646.69 mE

Source: ITI Report SS 1113352 on existing noise and vibration levels (2011)

C. Biological environment

1. Proximity to wildlife reserves and forest reserves 51. The proposed project location lies in a forest area, and about 168-ha of forest is estimated for inundation.The existing forest types within the inundated area as well as the surrounding envoirnment needs to be further studied to assess the habitat status of critically endangered and endangered species in the area and develop appropriate mitigatory measures. 52. Forest Conservation Department (FCD) has classified the forest cover within the catchment area under the categories of dry monsoon forest, open & sparse forest, shrub jungle, and non forest (Figure 6). Riverine forest type is not included in the FCD map. However, since Per Aru is a small river, a narrow strip of forest type along either sides of the Per Aru can be considered as riverine forest.Within the non forest area of FCD map, there exist land cover /land use types classified by the Survey Department (SD) topographical map of 1:50,000. They are scrub jungle, garden, paddy, water bodies and grasslands. Detail information on the “non forest” area of the FCD map was populated with the land use/ land cover types of the 1: 50,000

67 National Water Supply and Drainage Board EIA Study on Per Aru Reserv

topographical map of SD (Figure ?). According to present wildlife conservation map developed by the DWC,as shown in Figure 3, no wildlife conservation sites are located in close proximity of the proposed reservoir. The Integrated Environment Assessment (ISEA) report prepared in 2011 for the Northern Province proposes a jungle corridor to link Padaviya forest reserve located at Eastern side of the proposed reservoir and the wildlife sanctuary of the Giant’s reservoir located at the western side of the proposed reservoir. The proposed jungle corridor is shown in Figure 29.The forest cover maps incorporated with the proposed jungle corridor are shown in Figure 30 and Figure 31.

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 29 : Proposed elephant corridor

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 30 : Wildlife reserves, sencuries and proposed jungle corridor

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Figure 31 : Proposed elephant corridor and inundation area

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

2. Ecological status of the project area 53. The inundated area comprises of two land cover types namely, dry monsoon forest, and open & sparse forest, as classified by the FCD and scrubland classified by the Survey Department (Figure 8). Rest of the area comprises paddy cultivation, streams, and non forest lands. While the FCD map does not include riverine forest it is found in the project and surrounding environ either sides of the river Per Aru. The land cover extents and their types within the study area are shown in Table 16 and same details within the inundated area and 100-m buffer zone are shown in Table 17. Extents of different varieties of land cover within the catchment area including sample study area and reservoir inundation area are shown in Table 21.

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 72

Table 21 : Land cover types within the catchment area

Inundation Area Catchment Area Study Area (SA) LC in IA LC in IA LC in (IA) (CA) as a % as a % SA as a Land Cover (LC) Each Each Each LC Each Each of of % of Each LC Classification LC Area LC as a % LC LC as a similar similar similar as a % of of IA Area of of total Area of % of LC in LC in LC in total IA (ha) SA (ha) SA CA (ha) total CA SA CA CA Dry Monsoon Forest (DMF) 146 58 448 42 7521 30.132.5 1.9 6 Open Sparse Forest (OSF) 18 7 77 7 2248 923.4 0.8 3.4 Shrub (Sh) 0 0 0 0 875 3.5 0 0 0 Scrub (Sc) 4 2 160 15 2152 8.6 2 0.2 7.4 Non Forest (NF) 21 8 135 13 3009 12.1 15.6 0.7 4.5 Paddy (Pd) 60 24 202 19 3852 15.4 29.7 1.6 5.2 Chena (Ch) 0 0 0 0 1079 4.3 0 0 0 Water Bodies (WB) 1.5 1 29 2.9 1707 6.9 5.2 0.1 1.7 Garden (Gd) 0 0 14 1 2440 9.8 0 0 0.6 Road (Rd) 0 0 1 0.1 51 0.2 0 0 2 Rock (Rk) 0 0 0 0 15 0.1 0 0 0 Total LC Area 250.5 1066 24949

73 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

3. Per Aru upper catchment area

a. Habitat types in the upper catchment

54. Habitat types of the uppercatchment area were identified by the field investigation team under the categories of riverine forest, dry mixed evergreen forest, secondary distributed forest (shrub forest) and home gardens. Investigations were carried out up to Mamaduwa reservoir in the upper catchment.

i. Riverine forests

55. Riverine forests occur on either side of the Per Aru river. The vegetation comprises trees, shrubs and lianas. Kumbuk (Terminalia arjuna) was the most important tree species in terms of density, frequency, girth and stature and thus showing a character of Riparian Forest ecosystem. The other canopy trees were Kunu-Mella (Diospyros ovalifolia), and Timbiri (Diospyros malabarica),while the higher sub-canopy trees consisted of species such as Tammenna (Mischodon zeylanicus), Puwangu (Aglaia elaeagnoidea), Kunumella (Diospyros ovalifolia), and Dambu (Lepisanthes tetraphylla). Karanda (Pongamia pinnata), Kota-dimbula (Ficus hispida) and Attikka (Ficus racemosa) formed the lower levels among the tree flora. Shrub species in the Riparian Forest such as Bol-pana (Glycosmis mauritiana), Bulu-petta (Mallotus eriocarpus) and Mi-wenna (Polyalthia korinti) etc. represents the undergrowth of the forest. 56. An important medicinal aquatic plant; Cryptocoryne beckettii (Ati Udayan) which is listed as a Nationally Endangered and a threatened endemic species was observed in the river mostly as thick mats on the exposed river bed.

ii. Dry mixed evergreen forest

57. The dominant canopy trees of this ecosystem comprised Palu (Manilkara hexandra), Weera (Drypetes sepiaria), Buruta (Chloroxylon swietenia), Dambu (Lepisanthes tetraphylla) and Godakaduru (Strychnos nux-vomica) while Kunumella (Diospyros ovalifolia), Kiri-kon (Walsura triofoliolata), Tumpat-kurundu (Pleiospermium alatum), and Bu-seru (Premna tomentosa) etc dominate the sub-canopy layer. However, some individuals of Kunumella and Kiri-kon reach up to the canopy level. Of all trees in the Dry Mixed Evergreen Forest Weera is clearly the most important species in terms of density and frequency. The common shrubs consist of Bol-pana (Glycosmis mauritiana), Mi-wenna (Polyalthia korinti), Kuratiya (Phyllanthus polyphyllus), Kora-kaha (Memecylon umbellatum) and Wel-keppetiya (Croton aromaticus) etc. while Katu-keliya (Scutia myrtina) and Sudu-kala-wel (Derris parviflora) etc are the common lianas.

iii. Secondary disturbed forest (scrub forest)

58. Some of the most abundant species in the Shrub area are Kuratiya (Phyllanthus polyphyllus), Hin-katupila (Securinega leucopyrus), Andara (Dichrostachys cinerea), Heenkaramba (Carissa spinarum), Ganda-pana (Lantana camara) and Karapincha (Murraya koenigii) etc. while woody creepers (or lianas) such as Katu-keliya (Scutia myrtina), and Heen- eraminiya (Zizyphus oenoplia) often form thorny tangles over shrub. Some of the common tree species, although of low stature, are Maila (Bauhinia racemosa), Kohomba (Azadirachta indica), Bu-seru (Premna tomentosa), Ehela (Cassia fistula), Ma-dan (Syzygium cuninii) and Tumpat- kurundu (Pleiospermium alatum). There are also some large trees such as Palu (Manilkara

74 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir hexandra) and Kunumella (Diospyros ovalifolia) usually left uncut during clearing for chena cultivation.

iv. Home gardens

59. There were homegardens in the southern part of Upper Catchment of the Per Aru River.Most of such lands were used for different human activities such as building houses, home gardens, perennial cultivation, etc.

b. Flora in the Per Aru upper catchment

60. Table 22 shows the summary of the flora observed in the different habitat types in the Upper Catchment of Per Aru River. Species status are categorized as Endemic and Indigenous. Conservation sratus are categorized as Critically Endengered (CR), Endengered (EN), Vulnerable (VU), and Near Threatened (NT).

Table 22 : Distribution of the flora according to habitats

Habitat No. of Endemic Conservation Status Species Species River and Riverine 55 3 NT – 1, Forest Dry Mixed Evergreen 63 6 EN – 1, NT - 1 Forest Open scrublands 77 0 VU - 1 Homegardens 374 2 VU -3 Reservoirs and 90 1 CR -1, EN – 1, VU - 1 Associated Vegetation Paddy fields 36 0 0 Total 695 12 CR – 1, VU – 5, NT – 2, EN - 1 Conservation Status: CR – Critically Endangered, VU – Vulnerable, NT – Near Threatened,

61. The detail distribution of the endemic, threatened and vulnerable flora with respect to identified habitats are shown in Table 23.

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 75

Table 23 : Distribution of flora according to species & conservation status and habitat

Habitat Family Scientific Name Local Name Sp. Status Con. Status OS DF FO RR RA HG Araceae Cryptocoryne beckettii Athi-udayan E DNT + Euphorbiaceae Mallotus eriocarpus Bulu-petta E D + Flacourtiaceae Hydnocarpus venenata Makulu E D + Celastraceae Cassine glauca Neralu E D + + Fabaceae Derris parviflora Sudu-kalawel E D + Euphorbiaceae Mallotus eriocarpus Bulu-petta E D + Melastomataceae Memecylon Dodan-kaha E D + capitellatum Hippocrateaceae Salacia reticulata Himbutu E D NT + Ebenaceae Diosphyros ebenum Kaluwara E D EN + + Rubiaceae Mitragyna parvifolia Helamba VU + Euphorbiaceae Phyllanthus emblica Nelli VU + Euphorbiaceae Phyllanthus emblica Ratanelli VU + Amaranthaceae Achyranthes aspera Maduruthala CR + Rubiaceae Mitragyna parvifolia Helamba VU + Erythroxylaceae Erythroxyllum sp VU + Species Status: ED – Endemic, IN – Indigenous, Conservation Status: CR – Critically Endangered, EN – Endangered, VU-Vulnerable, NT – Near Threatened, Habitat: OS – Open Scrublands, DF – Degraded Forests, FO – Forests, RR – River and Riverine, RA – Reservoirs and Associated Vegetation, HG – Homegardens

76 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

c. Fauna in the Per Aru upper catchment

62. A good faunal diversity was present in the different habitats in the Upper Catchment and associated areas ie forests, homegardens, shrublands, reservoirs. Most of the birds species are common such as Common wood shrike, Pale billed flowerpacker, red wettled lapwing, white bellied drongo, baya weaver etc. Most common species were the red vented bulbul, common mynah, oriental magpie robin, Spotted Dove, Yellow billed babbler and white rumped munia. These birds species are not in the list of threatened catogeroius defined by the IUCN. 63. The common butterfly species White four ring and Common Indian crow found in the area. Papilio Polymnestor is an endemic butterfly species found in the area. They are not in the threatened list of IUCN. Table 24 shows the summary of the fauna observed in the different habitats of the Upper Catchment along with their conservation status.Table 25 shows detail the distribution according to species and conservation ststus and habitat in the upper catchment.

77 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir Table 24 : Summary of the fauna species according to the habitat Habitat Taxonomic No. of Endemic Conservation status Exotic Group Species Species Species Reservoir Birds 45 0 VU – 1 associated Butterflies 19 0 EN – 1, NT -1 Dragonflies 10 0 0 Mammals 14 2 EN – 1, VU – 3, NT - 2 Reptiles 5 0 0 Amphibians 5 0 0 Fishes 17 0 0 1 Dense Forest Birds 7 0 R/M - 1 Butterflies 10 1 EN - 1 Dragonflies 2 0 Mammals 2 1 Reptiles 1 0 Open Birds 27 0 NT - 1 Scrublands Butterflies 15 1 NT - 2 Dragonflies 5 0 Mammals 8 2 (1+1) VU - 2 Homegardens Birds 18 0 Butterflies 7 0 Dragonflies 4 0 Mammals 4 1 VU - 2 Reptiles 4 0 Amphibians 1 0 Paddy fields Birds 18 0 NT - 1 Butterflies 7 1 EN - 2 Dragonflies 4 0 Mammals 2 0 VU - 1 Reptiles 1 0 Amphibians 1 0 263 08 EN = 04, VU = 07, 01 NT= 05 Conservation Status: EN – Endangered, VU-Vulnerable NT – Near Threatened, R/M – Resident/Migrant

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 78 Table 25 : Distribution of fauna according to species & conservation status and habitat

Con. Habitat Type Scientific Name Local Name Sp. Status Status OS DF FO RR RA HG PA Butterflies Cirrochroa thais Tamil Yeoman NT + + Pachliopta jophon Ceylon rose ED EN + + Papilio Polymnestor Blue mormon ED + Birds Accipiter virgatus Besra VU + Chrysocolaptes Greater flameback NT + lucidus Cethosia nietneri Ceylon lace wing NT Mycalesis rama Cingalese Bush ED EN + Brown Udaspes folus Grass Demon EN + Mammals Ursus ursinus Sloth bear EN + Panthera pardus Leopard VU ++ Prionailurus viverrinus Fishing cat VU + Elephas maximus Asian elephant VU + Macaca sinica Toque monkey NT + + Semnopithecus priam Grey langur NT + Semnopithecus Purple faced leaf ED VU + vetulus monkey Moschiola meminna Mouse deer ED + Felis chaus Jungle cat VU + Ratufa macroura Giant squirrel ED VU + + Species Status: ED – Endemic, IN – Indigenous, Conservation Status: CR – Critically Endangered, EN – Endangered, NT – Near Threatened, Habitat: OS – Open Scrublands, DF – Degraded Forests, FO – Forests. RR – Riverine forest, RA – Reservoir Associated, HG – Homegardens, PA – Paddy fields,

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

4. Inundated area and downstream of the Dam

a. Habitats in the inundated area and downstream of the dam

64. There are six major natural and semi natural habitat types in the area. The forests, river, riverine forests, degraded or disturbed forests and open shrub lands (shrub lands with open grassy area) are the major natural habitat types present in the study area while the irrigation reservoirs and associated vegetation is the major semi natural habitat present in the area. In addition, few specific microhabitats were also identified within some of the above mentioned major natural habitat types (for example in the open shrub lands and forest habitat there are small seasonal waterlogged areas (water holes) that can be considered as a unique habitat. Figure 32 shows the study areas in the inundated area. Sampling was done in the entire inundated area and in area within 500-m on either side of the downstream up to 2.5-km from the proposed dam.

80 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Riverine forests Dry monsoon forest

Secondary degraded forest Shrub forest

Periyakulam Reservoir Paddy fields

Figure 32 : The habitat types in the inundated area

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir i. River

65. Per Aru can be classified as a perennial, slow moving, medium sized river. It undergoes major fluctuation in the flow dynamics during the wet and dry seasons. The river descends rapidly in the wet season and slows down considerably during the dry season. The substratum comprises mostly sand and mud. Large pools of water can be seen scattered along the river. Because of these differences many microhabitats are formed along the river. The herbaceous aquatic species Cryptocoryne beckettii (Ati Udayan in Sinhala) is the only aquatic plant observed in the river. This endemic plant that is also listed as an endangered (EN) plant species, is very common along the river and formed thick mats on the exposed river bed. Semi- aquatic herb Crinum defixum (Heen Tolabo) is also found scattered along the edge of the river. However, it is not abundant in this habitat. 66. The faunal assemblage observed in the river comprised 21 species of fish (including three endemic and one exotic species), one water insect, 8 species of aquatic snails and one bivalve. One recorded fish species is listed as near threatened (NT). A detailed discussion of the flora and fauna was recorded during the study is given in section below.

ii. Riverine forest

67. Riverine forest can be seen along both banks of the river as a thin belt. It is subjected to seasonal inundation due to flooding of the river banks during the heavy rain in wet or rainy season. The boundary of such habitat cannot be identified as it gradually merges with the immediate habitat. Plant species such as Terminalia arjuna (Kumbuk / Marutu), Diospyros malabarica (Timbiri / Panichchai), Hydnocarpus venenata (Makulu / Makul), Syzygium cumini (Madan / Naval), Filicium decipiens (Pehimbiya / Chitteraivempu), Madhuca longifolia (Mi / Illupai), Berrya cordifolia (Halmilla / Chavandalai) were observed closer to the water’s edge in the riverine forests. Manilkara hexandra (Palu / Palai), Lepisanthes tetraphylla (Dambu / Nekota), Drypetes sepiaria (Wira / Virai), Drypetes gardneri (Gal Wira) are the other common trees observed in the riverine forest. The undergstorey of the riverine forest was formed by plant species such as Glycosmis mauritiana, Dimorphocalyx glabellus (Weliwenna / Tentuikki), Ixora pavetta (Maha Ratambala / Kanmuttankirai), Ixora coccinea (Ratambala / Vedchi), Eugenia bracteata (Tembiliya / Kaya), Murraya koenigii (Karapincha / Karivempu), Clausena indica (Migon Karapincha / Pannai), Diospyros ovalifolia (Kunumella / Vedukkanari), Diospyros nummulariifolia, Miliusa indica (Kikili Messa), Polyalthia korinti (Ulkenda / Uluvintai). The ground layer comprised species such as Trichopus zeylanicus (Bim Pol) and Elytraria acaulis. Number of climbers such as Pothos scandens (Pota Wel), Combretum sp. Ventilago madraspatana (Yakkada Wel / Vempadam), Salacia reticulata (Kotala Himbutu), Derris parviflora (Kala Wel) were also observed in the riverine forest. 68. The plants observed in the riverine forests included one tree species listed as nationally endangered (EN), Diospyros ebenum (Kaluwara / Karunkali) and Margaritaria indicus (Karawu) and Vanda tessellata, a tree and epiphyte respectively, listed as nationally vulnerable (VU). 69. Several endemic plant species such as Semecarpus nigro-viridis (Badulla), Diospyros nummulariifolia, Drypetes gardneri (Gal Wira), Derris parviflora (Kala Wel), Hydnocarpus venenata (Makulu / Makul), Memecylon capitellatum (Dedi Kaha / Katti Kaya) were observed in the riverine forest. 70. Several plant species such as Crossandra infundibuliformis, Rhinacanthus nasutus (Anitta / Nagamulli), Semecarpus nigro-viridis (Badulla), Pothos scandens (Pota Wel), Pleurostylia opposita (Panakka / Chiru Piyari), Combretum sp., Mucuna atropurpurea (Buchariwa / Phandatullai), Hydnocarpus venenata (Makulu / Makul), Scolopia acuminata (Katu

82 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Kenda), Strychnos sp. Piper sylvestre (Wal Gam Miris), Glycosmis pentaphylla (Dodan Pana / Kulapannai), Dimocarpus longan (Mora / Nurai), Mimusops elengi (Munamal / Makil), Trichopus zeylanicus (Bim Pol) were recorded only in the riverine forest of the during the study.

iii. Forests

71. This was the most dominant habitat type observed within the project area. It can be generally classified in to the dry mixed evergreen forest type. The forests in the area appear secondary in origin that has established after clearance of primary forest for agriculture and human settlements in the past. These areas have been abandoned for a long period allowing forests to re-grow to its present form. An important microhabitat, isolated seasonal water logged areas (water holes), was found scattered within the forest. 72. The canopy of the forest is formed by species such as Manilkara hexandra (Palu / Palai), Drypetes sepiaria (Wira / Virai), Chloroxylon swietenia (Buruta / Moodudad Marum), Schleichera oleosa (Koon / Kula). The other dominant tree species observed in the forests habitat included Lepisanthes tetraphylla (Dambu / Nekota), Grewia helicterifolia (Bora Daminiya / Taviddai), Diospyros ebenum (Kaluwara / Karunkali). The undergrowth of the forest comprised of tree species such as Glycosmis mauritiana, Dimorphocalyx glabellus (Weliwenna / Tentuikki), Ixora pavetta (Maha Ratambala / Kanmuttankirai), Murraya koenigii (Karapincha / Karivempu), Clausena indica (Migon Karapincha / Pannai), Diospyros nummulariifolia, Miliusa indica (Kikili Messa), Polyalthia korinti (Ulkenda / Uluvintai), Tarenna asiatica (Tarana / Karanai), Memecylon capitellatum (Dedi Kaha / Katti Kaya), Phyllanthus polyphyllus (Kuratiya). Number of climbers such as Ventilago madraspatana (Yakkada Wel / Vempadam), Salacia reticulata (Kotala Himbutu), Derris parviflora (Kala Wel), Cissus latifolia (Wal Diya Labu), Ziziphus oenoplia (Heen Eraminiya / Churai), Carissa spinarum (Heen Karamba / Chiru Kila) were common among the forest vegetation. In addition plant species such as Oplismenus sp. is common in the ground layer and Acampe praemorsa is the commonest epiphyte observed in the forests. 73. The plants observed in the forest habitat included one tree species listed as nationally endangered (EN), Diospyros ebenum (Kaluwara / Karunkali) and Stenosiphonium cordifolium (Bu Nelu / Nelu) and Vanda tessellata, a tree and epiphyte respectively, listed as nationally vulnerable (VU). Further, plant species Tragia hispida (Wel Kahabiliya) and Mallotus repandus found in the forest habitat is listed as near threatened (NT) species. 74. The flora assemblage observed in the forest habitat also included several endemic plant species such as Uvaria sphenocarpa, Vernonia zeylanica (Pupula / Kappilay), Cassine glauca (Neralu Piyari), Diospyros nummulariifolia, Drypetes gardneri (Gal Wira), Derris parviflora (Kala Wel), Memecylon capitellatum (Dedi Kaha / Katti Kaya), Premna alstoni. 75. Several plant species such as Stenosiphonium cordifolium (Bu Nelu / Nelu), Uvaria sphenocarpa, Cassine glauca (Neralu / Piyari), Commelina kurzii, Sapium insigne (Tel Kaduru / Tilai), Jasminum auriculatum, Adiantum caudatum (Vala Venna), Premna alstoni were recorded only within the forest habitats present in the study area.

iv. Degraded forests

76. Some of the forest patches that are present in the study area are degraded due to various human activities such as felling of trees, forest clearance, etc. The degraded forests are characterized by the presence of an open canopy, thick understory, more climber species and more invasive species. The canopy of the forest is formed by Manilkara hexandra (Palu/ Palai), Drypetes sepiaria (Wira/Virai), Grewia helicterifolia (Bora Daminiya/Taviddai), Schleichera oleosa (Koon/ Kula), Lepisanthes tetraphylla (Dambu/Nekota). The understory of the degraded

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir forests comprised of plant species such as Glycosmis mauritiana, Murraya koenigii (Karapincha/ Karivempu), Clausena indica (Migon Karapincha/ Pannai), Catunaregam spinosa (Kukurumanna/ Karai), Phyllanthus polyphyllus (Kuratiya), Dimorphocalyx glabellus (Weliwenna/ Tentuikki), Diospyros nummulariifolia, Diospyros ferrea, Miliusa indica (Kikili Messa), Polyalthia korinti (Ulkenda/ Uluvintai) while Oplismenus sp. is commonly found on the ground layer of the degraded forests. The degraded forests had a high incidence of climbers such as Ventilago madraspatana (Yakkada Wel/ Vempadam), Derris parviflora (Kala Wel), Ziziphus oenoplia (Heen Eraminiya/ Churai), Carissa spinarum (Heen Karamba/ Chiru Kila). The plant assemblage observed in the degraded forest did not include any threatened species. However, Mallotus repandus observed in this habitat is listed as a near threatened (NT) species. The endemic plant species observed in this habitat included species such as Diospyros nummulariifolia, Drypetes gardneri (Gal Wira), Derris parviflora (Kala Wel), and Vernonia zeylanica (Pupula/ Kappilay).

v. Open scrublands

77. Open scrublands is the second most dominant habitat type observed in the study area. The open scrublands are characterized by open grassy areas scattered in between scrub patches. This type of a mosaic habitat pattern has resulted due to the agricultural practices that existed in this area in the past. Isolated seasonal water logged area (water holes) were observed scattered in the grassy areas within the open scrublands. These water holes functions as important microhabitats.

vi. Water bodies and associated vegetation

78. Open shrublands is the second most dominant habitat type observed in the study area. The open scrublands are characterized by open grassy areas scattered in between scrub patches. This type of a mosaic habitat pattern has resulted due to the agricultural practices that existed in this area in the past. Isolated seasonal water logged area (water holes) were observed scattered in the grassy areas within the open scrublands. These water holes functions as important microhabitats. 79. Only a few irrigation reservoirs were observed within the study area. These included Kaddiar Kulam, Velan Kulam, Periya Kulam, Chinna Kulam and Pawak Kulam. All of these are man made Reservoirs for agricultural purposes. However, these Reservoirs have become naturalized with time and support a natural assemblage of fauna and flora. Therefore in general these reservoirs can be considered as semi natural habitats

b. Flora in the inundated area and downstream of the dam

80. A total number of 279 plant species including 11 endemic, 6 nationally threatened and three nationally near threatened species were recorded during the field survey within the study area. Majority of the plant species recorded are herbaceous species (95) followed by trees species (92), climbers (63), shrubs (25) and epiphytes (4). About 4 % of the recoded plant species are endemic to the country and about 87 % of the recorded plant species are native to Sri Lanka while the remaining 9 % of the recoded plant species are exotic to the country. This indicates that most of these habitats have not had a major human influence during recent times. Summary of the plant species recorded during the field survey within the study area is listed in Table 26.

84 National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Table 26 : Summary of the plant species according to plant variety

Plant Type No. of Conservation Status Endemic Native Exotic Species Species Species Species Tree 92 EN – 1, VU – 2, NT – 2 6 82 4 Shrub 25 VU – 1 1 22 2 Herb 95 EN – 1 1 78 16 Epiphyte 4 VU – 1 0 4 0 Climber or 63 NT – 1 3 58 2 Creeper Total 279 EN – 2, VU – 4, NT- 3 11 (4%) 244 (87%) 24 (9%) Conservation Status: EN – Endangered, VU – Vulnerable, NT – Near Threatened Source: Biotic Survey done by ADB5, 2011 81. Out of 11 recorded endemic plant species within the study area during the field survey one herbaceous species, Cryptocoryne beckettii (Ati Udayan in Sinhala) that is present in the river (Per Aru) is listed as a nationally Endangered (EN). The other nationally endangered tree species is Diospyros ebenum (Kaluwara in Sinhala and Karunkali in Tamil) that was observed in forests, riverine forests and vegetation associated with Reservoirs. Four other plant species listed as Nationally Vulnerable (VU) was also observed in the study area. Further, three non endemic plant species observed within the study area is listed as nationally Near Threatened (NT) species. The distribution of endemic, nationally threatened and near threatened plant species according to the habitats where these plants are observed in the study area is listed in Table 27.and summery of the distribution of plant species according to habitats in the study area listed in Table 28.

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board

Table 27 : Distribution of flora according to species & conservation status and habitat

Family Species Spe. Spe. Con. Habitats Variety Status Status OS DF FO RR RA Acanthaceae Stenosiphonium cordifolium S IN VU + Anacardiaceae Semecarpus nigro-viridis T ED + Annonaceae Uvaria sphenocarpa C ED + Araceae Cryptocoryne beckettii H ED EN + Asteraceae Vernonia zeylanica C ED + + + + Celastraceae Cassine glauca T ED + Ebenaceae Diospyros ebenum T IN EN + + + Ebenaceae Diospyros montana T IN NT + Ebenaceae Diospyros nummulariifolia T ED + + + + + Euphorbiaceae Drypetes gardneri T ED + + + + + Euphorbiaceae Mallotus repandus T IN NT + + + + Euphorbiaceae Margaritaria indicus T IN VU + + Euphorbiaceae Tragia hispida C IN NT + + Fabaceae Derris parviflora C ED + + + + + Flacourtiaceae Hydnocarpus venenata T ED + Melastomataceae Memecylon capitellatum T ED + + Orchidaceae Vanda tessellata Ep IN VU + + + Rubiaceae Mitragyna parvifolia T IN VU + + Verbenaceae Premna alstoni S ED + Species Variety: T – Tree, S – Shrub, H – Herbaceous, C – Climber or Creeper, Ep – Epiphyte, Species Status: IN – Indigenous, ED – Endemic, Conservation Status: EN – Endangered, VU – Vulnerable, NT – Near Threatened, Habitat: OS – Open Scrublands, DF – Degraded Forests, FO – Forests, RR – River and Riverine, RA – Reservoirs and Associated Vegetation Source: Biotic Survey done by ADB5, 2011 85

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 86 Table 28 : Distribution plant species according to habitats

Habitat Type No. of Conservation Status Endemic Native Exotic Species Species Species Species

River and Riverine 117 EN – 2 , VU – 2 7 107 3 Forests 104 EN – 1 , VU – 2, NT – 2 8 91 5 Degraded Forests 60 NT – 1 4 55 1 Open Scrublands 160 VU – 1, NT – 1 4 141 15 Reservoirs and Associated 175 EN – 1 , VU – 3, NT – 3 4 148 23 Vegetation Water Holes in Open 17 0 0 17 0 Scrublands Water Holes in Forest 7 0 0 7 0 Conservation Status: EN – Endangered, VU – Vulnerable, NT – Near Threatened Source: Biotic Survey done by ADB5, 2011

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

c. Fauna of the inundated area and the downstream of the dam

82. A total number of 316 faunal species including 28 endemic and 3 proposed endemic were recorded in the study area during the field survey. Three recorded species including one fish species and two land snails are exotic to the country. Birds emerged to be the most diverse taxonomic group in the Per Aru basin where out of the recorded 316 faunal species recorded birds comprised of 109 species. Butterflies and Reptiles were the second and third most abundant taxa recorded during the survey with 60 and 28 species respectively. Table 29 shows the summary of the faunal species recorded during the study.

Table 29 : Summary of the faunal species recorded during the field study

Taxonomic No. of Endemic Conservation status Exotic Group Species Species Species Birds 109 ED-3, PE – 3 VU – 1, NT – 5 0 Butterflies 60 0 CR – 1, VU – 2, NT – 5 0 Dragonflies 26 3 0 0 Mammals 24 3 VU – 6, NT – 4 0 Reptiles 28 4 VU – 2, NT – 1 0 Amphibians 16 2 0 0 Fishes 21 3 NT – 1 1 Land Snails 21 10 CR – 2, EN – 1, NT – 3 2 Aquatic Snails 08 0 0 0 Aquatic 01 0 0 0 Bivalves Water Insects 01 0 0 0 Tarantulas 01 0 0 0 Total 316 ED- 28, PE – 3 CR – 3, EN – 1, VU – 11, NT – 19 3 Species Status: ED – Endemic, PE – Proposed Endemic, Conservation Status: CR – Critically Endangered, EN – Endangered, VU – Vulnerable, NT – Near Threatened. Source: Biotic Survey done by ADB5, 2011

83. Out of the 28 endemic and 03 proposed endemic faunal species recorded during the field survey within the study area, three species are listed as critically endangered (CR) and one species as endangered. These included land snail species, Euplecta colletti and Japonia vesca, one butterfly species, Mycalesis visala listed as Critically Endangered (CR) and one land snail species Theobaldius subplicatulus listed as Endangered (EN).

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

i. Birds

84. Birds were the prevalent group of fauna observed during the Per Aru Biotic Resource survey where a total number of 109 bird species were recorded in all the habitats within the study area. This included three endemic species, three proposed endemic species, one nationally vulnerable (VU) species and five nationally near threatened species. They have diversified among all five habitats identified in Per Aru displaying the highest abundance in each habitat compared to all other taxonomic groups of fauna. Summary of the distribution of the recorded bird species according to habitats in the study area is listed in Table 30. The distribution of endemic, proposed endemic, nationally threatened and near threatened birds species according to habitats are listed in Table 31.

Table 30 : Summary of the distribution of the birds according to habitats

No. of Species Habitats Conservation Species Species Status River and Riverine 59 ED-3, PE – 3 NT – 3 Forest Forests 33 ED-3, PE – 2 NT – 2 Degraded Forests 17 ED-2, PE – 1 NT – 1 Open Scrublands 55 ED-3, PE – 2 NT – 3 Reservoir and 91 ED-3, PE – 3 VU – 1, NT – 5 Associated Vegetation Total 109 ED-3, PE – 3 VU – 1, NT – 5 Species Status: ED – Endemic, PE – Proposed Endemic, Conservation status: VU – Vulnerable, NT – Near Threatened Source: Biotic Survey done by ADB5, 2011

Table 31 : Distribution of birds according to species & conservation status and habitat

Spe. Con. Scientific Name Local Name Status Status Habitat OS DF FO RR RA Elanus caeruleus Black Wing Kite BR NT + Ceyx erithacus Oriental Dwarf Kingfisher BR NT + + + Anthracoceros coronatus Malabar Pied Hornbill BR NT + + Ocyceros gingalensis Sri Lanka Grey Hornbill ED + + + + Ciconia episcopus Woolly Necked Stork BR NT + + + Pompadour Green Treron pompadora Pigeon PE + + + +

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Surniculus lugubris Drongo Cuckoo BR VU + Gallus lafayetii Sri Lanka Jungle Fowl ED + + + + + Pycnonotus melanicterus Black Crested Bulbul PE + + + Megalaima rubricapilla Crimson Fronted Barbet PE + + + + Pellorneum Sri Lanka Brown Capped fuscocapillum Babbler ED NT + + + + + Species Status, ED – Endemic, PE – Proposed Endemic, BR – Breeding Resident, Conservation Status: VU – Vulnerable, NT – Near Threatened, Habitat: OS -Open Scrublands, DF – Degraded Forests, FO – Forests, RR – River and Riverine, RA – Reservoir and Associated Vegetation Source: Biotic Survey done by ADB5, 2011

ii. Butterflies

85. Total number of 60 butterfly species was recorded in all five habitats during the field survey within the study area. This includes three nationally threatened species and five nationally near threatened species. Similar to the birds, they are also widespread in all five habitats (Table 32). However, the Critically Endangered Tamil Bush Brown (Mycalesis visala), was recorded only in the Open Shrublands . None of the butterflies recorded during the study are endemic to Sri Lanka.

Table 32 : Summary of the distribution of the butterflies according to habitats

Habitats No. of Species Conservation Status River and Riverine Forest 33 VU – 2, NT – 2 Forests 30 VU – 1, NT – 3 Degraded Forests 18 NT – 1 Open Scrublands 34 CR – 1, NT – 1 Reservoirs and Associated 34 NT – 1 Vegetation Total 60 CR – 1, VU – 2, NT – 5 Conservation Status: CR – Critically Endangered, VU – Vulnerable, NT – Near Threatened,

86. The distribution of Butterflies according to species & conservation ststus and habitat are shown in Table 33.

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Table 33 : Distribution of butterflies according conservation status

Spe. Con. Habitat Scientific Name English Name Status Status OS DF FO RR RA Badamia exclamationis Brown Awl IN VU + + Anthene lycaenina Pointed Ciliate Blue IN VU + Neopithicops zalmora Quaker IN NT + + Charaxes psaphon Tawny Rajah IN NT + Charaxes solon Black Rajah IN NT + Cirrochroa thais Tamil Yeoman IN NT + + Mycalesis visala Tamil Bush Brown IN CR + Colotis amata Small Salmon Arab IN NT + + Species Status: IN – Indigenous, Conservation Status: CR – Critically Endangered, VU – Vulnerable, NT – Near Threatened, Habitat: OS – Open Scrublands, DF – Degraded Forests, FO – Forests, RR – River and Riverine, RA – Reservoir and Associated Vegetation Source: Biotic Survey done by ADB5, 2011

iii. Dragonflies

87. A total 26 dragon fly species were found in all five habitats surveyed during the field study (Table 34). These include three species that are endemic to Sri Lanka. The recorded endemic species had a limited distribution within the study area where Rapacious Flange tail (Ictinogomphus rapax) and Adam’s Gem (Libellago adami) were restricted to the Reservoirs and Associated Vegetation and River and Riverine areas respectively (Table 35). Neither nationally threatened nor near threatened dragonfly species were recorded during the study.

Table 34 : Summary of the distribution of the dragonflies according to habitats

Habitats No. of Species Endemic Species River and Riverine Forest 14 2 Forests 8 0 Degraded Forests 8 1 Open Scrublands 17 1 Reservoir and Associated Vegetation 15 1 Total 26 3

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Table 35 : Distribution of dragonflies according to species status and habitat

Scientific Name English Name Spe. Habitat Status OS DF FO RR RA

Libellago adami Adam’s Gem ED + Ictinogomphus rapax Rapacious Flangetail ED + Prodasineura sita Stripe-headed ED + + + Threadtail Species Status: ED – Endemic, Habitat: OS – Open Scrublands, DF – Degraded Forests, FO – Forests, RR – River and Riverine, RA – Reservoir and Associated Vegetation Source: Biotic Survey done by ADB5, 2011

iv. Mammals

88. A total number of 24 mammal species was recorded from all five habitats present in the study area in more or less similar densities. This included three species that are endemic to Sri Lanka, six nationally vulnerable (VU) species and four nationally near threatened species. When considering the three endemic species recorded during the survey, Purple-faced Leaf Monkey (Semnopithecus vetulus) had a considerably large population but was limited only to the Per Aru riverine area and Kaddiar kulam Reservoir and its associated vegetation. The endemic species, Sri Lanka Mouse Deer (Moschiola meminna), has been recorded in the Open Scrubland only. The Grey Slender Loris (Loris lydekkerianus) and Pangolin (Manis crassicaudata) categorized as Near Threatened Species were observed only during night transects. A summary of the distribution of the recorded mammal species according to habitats in the study area is listed in Table 36. The distribution of endemic, nationally threatened and near threatened mammal species according to habitat listed in Table 37.

Table 36 : Summary of the distribution of the mammals according to habitats

Habitats No. of Species Endemic Species Conservation Status River and Riverine Forest 14 2 VU – 4, NT – 2 Forests 12 1 VU – 2, NT – 3 Degraded Forests 7 0 VU – 1, NT – 1 Open Scrublands 11 2 VU – 2, NT – 1 Reservoirs and 9 2 VU – 3, NT – 2 Associated Vegetation Total 24 3 VU – 6, NT – 4 Conservation Status: VU – Vulnerable, NT Near Threatened. Source: Biotic Survey done by ADB5, 2011

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Table 37 : Distribution of mammals according to conservation status

Scientific Name English Name Spe. Con. Habitat Status Status OS DF FO RR RA Macaca sinica Sri Lanka Toque Monkey ED NT + + + + Semnopithecus Purple-faced Leaf ED VU + + vetulus Monkey Semnopithecus priam Grey Langur IN NT + + + Elephas maximus Elephant IN VU + Felis chaus Jungle Cat IN VU + Prionailurus viverrinus Fishing Cat IN VU + + Loris lydekkerianus Grey Slender Loris IN NT + Manis crassicaudata Pangolin IN NT + Lutra lutra Otter IN VU + Ratufa macroura Giant Squirrel IN VU + + + + + Moschiola meminna Sri Lanka Mouse Deer ED + Species Status: ED – Endemic, IN – Indigenous, Conservation Status: VU – Vulnerable, NT – Near Threatened, Habitat: OS – Open Scrublands, DF – Degraded Forests, FO – Forests, RR – River and Riverine, RA – Reservoir and Associated Vegetation, Source: Biotic Survey done by ADB5, 2011

v. Reptiles

89. Among all taxonomic groups recorded during the survey, Reptiles have the third highest species composition within the study area. As shown in Table 38, a total number of 28 reptile species was recorded comprising four endemic species, two nationally vulnerable (VU) species and one nationally near threatened species. When considering their distribution in the five habitats, their abundance appeared to be high in Reservoirs and associated areas compared to the other four habitats. Further, three endemic species out of the total of four species recorded during the survey was also found within this habitat type only (Table 39).

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Table 38 : Summary of the distribution of the reptiles according to habitats

Habitats No. of Endemic Conservation Status Species Species River and Riverine Forest 10 1 VU – 1, NT – 1 Forests 5 0 0 Degraded Forests 3 0 0 Open Scrublands 11 2 0 Reservoirs and Associated 19 3 VU – 1 Vegetation Total 28 4 VU – 2, NT – 1 Conservation Status: VU – Vulnerable, NT – Near Threatened, Source: Biotic Survey done by ADB5, 2011

Table 39 : Distribution of reptiles according to conservation status

Habitat Spe. Con. Species Name Common name Status Status OS RR RA Otocryptis nigristigma Black Spotted ED + + Kangaroo Lizard Melanochelys trijuga Parker’s Black IN NT + Turtle Lycodon osmanhilli Flowery Wolf ED + Snake Xenochrophis asperrimus The Checkered ED + Keelback Lankascincus fallax Common Lanka ED + + Skink Geochelone elegans Indian Star IN VU + Tortoise Lissemys punctata Flapshell Turtle IN VU + Species Status: ED – Endemic, IN – Indigenous, Conservation Status: VU – Vulnerable, NT – Near Threatened, Habitat: OS- Open Scrublands: DF – Degraded Forests, FO – Forests, RR – River and Riverine, RA – Reservoir and Associated Vegetation, Source: Biotic Survey done by ADB5, 2011

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

vi. Amphibians

90. A total number of 16 amphibian species including two endemic species was recorded from all five habitats during the field survey. A summery of the distribution of the recorded amphibian species according to habitats in the study area listed in Table 40. Of these the two endemic amphibian species, Sri Lanka Wood Frog (Rana gracilis) and Common Hour-glass Tree Frog (Polypedates crucige), were observed in the forest and Riverine areas during both day and night transects (Table 41).

Table 40 : Summary of the distribution of the amphibians according to habitats

Habitats No. of Species Endemic Species

River and Riverine Forest 12 2 Forests 8 2 Degraded Forests 0 0 Open Scrublands 4 0 Reservoirs and Associated Vegetation 8 1

Total number of varieties 16 2 Source: Biotic Survey done by ADB5, 2011

Table 41 : Distribution of amphibians according to species status and habitat

Spe. Habitat Species Name Common Name Status FO RR RA Polypedates Common Hour-glass ED + + cruciger Tree Frog Rana gracilis Sri Lanka Wood Frog ED + + +

Species Status: ED – Endemic, Conservation Status: FO – Forests, RR – River and Riverine, RA – Reservoir and Associated Vegetation, Source: Biotic Survey done by ADB5, 2011

vii. Land snails

91. A total of 21 species of land snails were recorded in the study area. Of these ten species are endemic to Sri Lanka. Out of the 21 species of land snails recorded, two are recorded as critically endangered species, one is listed as endangeded species while a further three species are listed as nationally near threatened species. They have been distributed in almost all the habitats surveyed. However, the species richness seems to be comparatively high in the river and riverine forest area. A summery of the distribution of the recorded land snail species

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir according to habitats in the study area listed in Table 42. The distribution of endemic, nationally threatened and near threatened land snail species according to habitat listed in Table 43.

Table 42 : Distribution of the land snails according to habitats

Habitats No. of Endemic Conservation Status Exotic Species Species Species River and Riverine Forest 19 10 CR – 2, EN – 1, NT – 3 1 Forests 14 7 CR – 2, EN – 1, NT – 1 0 Degraded Forests 11 6 CR – 1, EN – 1, NT – 2 0 Open Scrublands 18 8 CR – 1, EN – 1, NT – 3 1 Reservoirs and Associated 7 2 EN – 1, NT – 1 0 Vegetation Total number of varieties 21 10 CR – 2, EN – 1, NT – 3 2 Conservation Status: CR – Critically Endangered, EN – Endangered, NT – Near Threatened, Source: Biotic Survey done by ADB5, 2011

Table 43 : Distribution of land snails according conservation status

Spe. Con. Habitat Family Scientific Name Status Status OS DF FO RR RA Ariophantidae Euplecta colletti ED CR + + + + Cyclophoridae Japonia vesca ED CR + + Cyclophoridae Aulopoma ED + + + + hofmeisteri Glessulidae Glessula ED + + + ceylanica Glessulidae Glessula lankana ED + + + Bulimininae Mirus panos ED + + + Cyclophoridae Theobaldius sp. ED + + Cyclophoridae Theobaldius ED EN + + + + + subplicatulus Cyclophoridae Cyc!ophorus ED NT + + menkeanus Ariophantidae Euplecta IN NT + + + semidecussata Cyclophoridae Pterocyclus IN NT + + + + + cumingi Camaenidae Beddomea ED + + + + + trifasciatus

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir Species Status: ED – Endemic, IN – Indigenous, Conservation Status: CR – Critically Endangered, EN – Endangered, NT – Near Threatened, Habitat: OS – Open Scrublands, DF – Degraded Forests, FO – Forests, RR – River and Riverine, RA – Reservoir and Associated Vegetation Source: Biotic Survey done by ADB5, 2011

viii. Fishes

92. Fish sampling was carried out in two main habitats identified within the study area; Per Aru river and the five Reservoirs. During the sampling period, a total number of 21 fish species were recorded out of which three are endemic species and one species is listed as nationally near threatened. A summery of the distribution of the recorded fish species according to habitats in the study area listed in Table 44. The distribution of endemic and near threatened fish species according to habitat listed in Table 45. It should be highlighted that all three endemic fish species and the near threatened fish species found during the survey has been recorded in the Per Aru River.

Table 44 : Summary of the distribution of the fishes

Habitats No. of Endemic Conservation Exotic Species Species Status Species Main River 21 3 NT – 1 1 Reservoirs 6 0 0 1 Total number of varieties 21 3 NT – 1 1 Conservation Status: NT – Near Threatened, Source: Biotic Survey done by ADB5, 2011

Table 45 : Distribution of fishes according to conservation status

Family Scientific Name English Name of fishes Spe. Con. Habitat Status Status RI Anabantidae Anabas Climbing perch IN NT + testudineus Cyprinidae Esomus Flying barb / Bearded ED + thermoicos rasbora Cyprinidae Labuca lankensis Lanka labuca ED + Cyprinidae Puntius singhala Filamented Barb ED + Species Status: ED – Endemic, IN – Indigenous, Conservation Status: NT – Near Threatened. Habitat: RI - Main River (Per Aru), Source: Biotic Survey done by ADB5, 201

ix. Other fauna (aquatic snails, bivalves, water insects, tarantulas)

93. In addition to the above-mentioned taxonomic groups, 8 freshwater snail species, one freshwater bivalve species, one freshwater insect and one tarantula species were recorded

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir during the field survey within study area. They are not in the category of threatened species defined by IUCN. A Summery of the recorded other fauna species in the study area listed in Table 46.

Table 46 : Summary of the recorded other fauna species during the field study

Taxonomic Group No. of Species Aquatic Snails 8 Aquatic Bivalves 1

Water Insects 1 Tarantulas 1 Source: Biotic Survey done by ADB5, 2011

5. Species habitat of potential resettlement land for inundated agricultural lands

a. Habitat

94. Two sites had been identified by the District Secretary/.Divisional Secretary Vavuniya as alterantive lands for the agricultural lands that will be lost due to the Proejct. These lands are located under 03 abandoned irrigation reservoirs of which two are located adjoining to each other at the right bank of the Per Aru. They are katkulam reservoir and Pathiniyar kulam reservoir. The other one, katkulam reservoir is located at the left bank. Identifing more alternative lands as shown in Figure 4, is still in progress. Under these reservoirs, paddy cultivation had been carried out many many years ago but they are now abandoned and the present land use is secondary dry mixed evergreen forest.

b. Flora

95. The vegetation and their taxonomic and conservation status in Dry Mixed Evergreen Forests in Katkulam is shown in Table 47.Only one shrub (Salacia Reticula) has been found to be near threatened in the area.

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Table 47 : The floristic composition and the conservation & species status

Family Species Common Life Con. Species Name Form Status Status ED N M Meliaceae Aglaia elaeagnoidea Puwangu Tr NM Lauraceae Alseodaphne Wewarana Tr N semecarpifolia Rutaceae Atalantia monophylla Perunkuruntu S N (T) Fabaceae Bauhinia racemosa Maila Tr NM Rubiaceae Benkara malabarica Pudan (T) S-Tr N Capparaceae Capparis brevispina Wal-dehi S N Capparaceae Capparis zeylanica Welangiriya S N Apocynaceae Carissa spinarum Heen-karamba S N M Boraginaceae Carmona retusa Heen-tambala S N M Fabaceae Cassia fistula Ehela Tr NM Celastraceae Cassine glauca Neralu Tr ED Rutaceae Chloroxylon Buruta Tr N swietenia Rutaceae Clausena indica Migonkarapinc S NM ha Boraginaceae Cordia monoica Naruvilli (T) Tr N M Euphorbiaceae Croton aromaticus Wel-keppetiya SS N Fabaceae Derris parviflora Sudu-kalawel L ED Fabaceae Derris scandens Kala-wel L N Sapindaceae Dimocarpus longan Mora T NM Euphorbiaceae Dimorphocalyx Weli-wenna S/T N M glabellus Ebenaceae Diospyros ebenum Kaluwara Tr N Ebenaceae Diospyros ferrea Kaluhabaraliya Tr N Ebenaceae Diospyros Timbiri Tr NM malabarica Ebenaceae Diospyros ovalifolia Kunumella Tr N Euphorbiaceae Drypetes sepiaria Wira Tr N Flacourtiaceae Flacourtia indica Katu-kurundu Tr N M

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Rutaceae Glycosmis Bol-pana S N mauritiana Tiliaceae Grewia carpinifolia Keliya SS N Tiliaceae Grewia helicterifolia Bora-daminiya Tr N Ulmaceae Holoptelea Goda-kirilla Tr N M integrifolia Linaceae Hugonia mystax Bu-getiya SS NM Apocynaceae Ichnocarpus Kiri-wel H NM frutescens Rubiaceae Ixora pavetta Goda-ratmal Tr N Oleaceae Jasminium auriculata H N Sapindaceae Lepisanthes Gal-kuma Tr N senegalensis Sapindaceae Lepisanthes Dambu Tr N tetraphylla Euphorbiaceae Mallotus eriocarpus Bulu-petta S ED Sapotaceae Manilkara hexandra Palu Tr NM Celastraceae Maytenus Kattamberiya S N emarginata Melastomataceae Memecylon Dodan-kaha S ED capitellatum Melastomataceae Memecylon Tr N sylvaticum Melastomataceae Memecylon Kora-kaha S NM umbellatum Rubiaceae Mitragyna parvifolia Helamba Tr NM Annonaceae Mitrephora Tr N heyneana Rutaceae Murrya koenigii Karapincha S-Tr N M Ochnaceae Ochna lanceolata Bo-kera S NM Euphorbiaceae Phyllanthus Kuratiya S N polyphyllus Rutaceae Pleiospermium Tumpatkurund Tr N alatum u Celastraceae Pleurostylia opposita Panakka Tr N Annonaceae Polyalthia korinti Mi-wenna S N Annonaceae Polyalthia longifolia O-wila Tr N Verbenaceae Premna tomentosa Bu-seru Tr NM

100

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir

Sterculiaceae Pterospermum Velang Tr NM suberifolium Hippocrateaceae Reissantia indica L N

Hippocrateaceae Salacia reticulata Himbutu SS NT ED

Rhamnaceae Scutia myrtina Katu-keliya L N Euphorbiaceae Securinega Heen-katu-pila S N M leucopyrus Loganiaceae Strychnos nux- Goda-kaduru Tr N M vomica Rubiaceae Tarenna asiatica Tarana S-Tr NM Rutaceae Toddalia asiatica Kudu-miris SS-L N M Rhamnaceae Ventilago Yakada-wel L N M maderaspatana Verbenaceae Vitex altissima Milla Tr N Meliaceae Walsura trifoliolata Kiri-kon Tr NM Rhamnaceae Zizyphus oenoplia Heeneraminiya SS-L N Veriety of Species: L- Liana, Tr-Tree, S-Shrub, H-Herbaceous or semi-woody vine, SS-Scandent shrub Conservation Status: NT - Threatened Species Status: ED - Endemic I - Introduced, N - Native M - Medicinal, Source: Biological survey coinducted by the Project, 2011

101

National Water Supply and Drainage Board EIA Study on Per Aru Reservoir D. Human settlement and land use 96. All data in this section were obtained from the report of the social economic survey conducted for the preparation of resettlement plan forthis project.

1. Settlement of the affected population 97. The study area encompasses two administrative divisions namely, Vavuniya and Vavuniya South. The catchment area of the proposed reservoir falls within the Vavuniya South Division, while the reservoir and its downstream within the Vavuniya Division. The project- affected families are mostly rural, and many of them depend on agriculture for their livelihood. Unemployment is high (20%) among them and could be attributed to slow growth of agro-based industries and the lack of employment opportunities in the area. 98. Ninety three percent of the affected families are Tamils. The remaining ethnic groups are Moors (5%) and Sinhalese (2%). Majority (78%) of affected families are nuclear families, and 22% are extended families. There are 34 vulnerable households among the affected families including 13 female-headed families. No family will be physically displaced because of the sub project. It will however affect 03 temporary houses (huts), 06 masonry wells, 05 ground water wells, and 01 Hindu kovil (temple). 99. The subproject will impact on cultivated lands causing imposing economic displacement of to 107 families. The inundation area of the proposed reservoir and the 100-m buffer zone around it cover 102 ha of land of which 79 ha are paddy land. On the remaining land of 23 ha, farmers cultivate seasonal crops under chena (slash-and-burn) cultivation method. There are 130 claimants to these lands either sole or joint land users. They are members of the affected 107 families. Nineteen percent of claimants possess land title deeds, while 17% hold 'cultivation permits' from the Government. Another 3% received land grants or “Jayaboomi” deeds from the Government. 24% of claimants are registered as 'cultivators' at the Agrarian Service Center. The other claimants (37%) do not have any documents to show their rights over the land they possess and cultivate. The Resettlement Plan 2012 of the subproject indicates that 54% of the claimants have been cultivating the land for more than 25 years, while 9% have started cultivation within the past 5 years. The project authorities will provide land for claimants under the land-for-land compensation package.

2. Population characteristics of the affected population 100. Population distribution of the 03 GN Divisions in the inundation area are shown in Table 48.

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Table 48 : Population by Grama Niladhari divisions affected by the inundation

Puthukulam Sastrikoolankulam Paranaddakal Family Status GN Division GN Division GN Division Family Pop. Family Pop. Family Pop. Resettlement & Relocation 142 392 665 2,413 180 626 Sub Family 8 32 33 100 Permanent 12 36 Displaced Families 217 934 442 1838 Temporary Attachment – released 52 215 20 71 from Welfare Centres Total 431 1609 1160 4422 180 626 • Pop – Population 101. Table 49 shows the sex of the affected population in the study area. This differs from the district sex percentages of 51.7% males to 48.3% females.

Table 49 : The sex of the affected population in the study area.

Male Female

54.43% 45.56 %

Source: Resettlement Plan for Vavuniya, 2012 102. Table 50 shows the population by age groups in the inundated area and the 100 meter buffer zone.

Table 50 : Population by age group

0-5 years 6-15 years 16-30 years 31-45 years 46-60 years 60>years

4.44% 17.16% 28.29% 16.27% 21.01% 11.83%

Source: Resettlement Plan for Vavuniya, 2012 103. The age profile shows a higher percentage of population representing the age category of 16-30 years followed by 46-60 years and 16-30 years. It is comparatively a lesser number in the age category of 0-5 years to the district level 27.2% (Household Income and Expenditure Survey 2009/10 of the Department of Census and Statistics). This could be attributed to decline in natural growth trend and delay of marriage among youth. The age above 60 years category is little more than the district level of 9.2% (Household Income and Expenditure Survey 2009/10 of the Department of Census and Statistics) among the Affected People. The decline in the

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir population growth is the result of rising educational levels of women and wide knowledge and awareness on reproductive health and also war. 104. Marital status of the population in the affected area is shown in Table 51.

Table 51 : Marital status of the population in the affected area

Married Unmarried Widow/widower Divorced Separated

46.45% 46.45% 5.33% 0% 0.89%

Source: Resettlement Plan for Vavuniya, 2012 105. The marital status of the population presents a different picture with a smaller number of widowed compared to the national average of 7.8% and the district average of 6.6%. Divorced or separated is negligible among the project affected households. (Household Income and Expenditure Survey 2009/10 of the Department of Census and Statistics). The percentage of unmarried category is higher than the national and district average. The national and district average of unmarried stands 33.4 and 39.2 respectively. This may be due to late marriage and employment migration as well as available open avenue for female education. 106. Table 52 shows the number of family members in the households in the affected area.

Table 52 : No of members in the household in the affected area.

2 Member 3 Member 4 Member 5 Member 6 Member 7 Member 11.84% 17.11% 22.37% 23.68% 18.42% 6.58% Source: Resettlement Plan for Vavuniya, 2012 107. The average family size in the area is 4.44 persons which is lower than the national average of 4.9 for the poor and higher than the national average of 3.9 for the non poor. (Household Income and Expenditure Survey 2009/10 of the Department of Census and Statistics). 24% of the household among the affected household are 5 members family. 108. Table 53 shows the educational attainments of the affected persons.

Table 53 : Educational attainments of the affected persons

Grade 1-V Grade VI- Passed Passed Undergraduates / Ordinary Level Ordinary Level Advanced Level graduates

16.86% 24.26% 26.92% 20.71% 5.03% Source: Resettlement Plan for Vavuniya, 2012 109. Illiteracy is almost negligible among the Affected People. The standard of education is high with 26.92% passing the GCE (Ordinary Level) Examination and 20.71% passing GCE (Advance Level) Examintion (both examinations are conducted by the Deprtment of Examinations of GOSL). The percentage of those qualified in O/L and A/L is above the national figures which stand at 14.7% and 11.2% respectively as well as district figure of O/L 11.7% and 6.5% of A/L. (Labor Force Survey, 2009/10 Department of Census and Statistics ). Higher

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir educational attainments could be attributed to parental aspirations for educating the children and proximity to a major centre of culture and education.

3. Income generation sources and patterns 110. Table 54 shows the occupational trends of the affected persons;

Table 54 : The occupational trends of the affected persons

Occupation % Farming own land 16.5 Agriculture labor 3.5 Non agriculture labor 2.7 Commercial activities 4.7 Executives 1.2 Employed in other grades 5.6 Housewife 9.7 Unemployed 20.1 Others 5.8 Students 30.2 Source: Resettlement Plan for Vavuniya, 2012 Note: Other category denotes fishing, weaving etc. 111. The population of the Affected People is mostly rural and many households depend on agriculture. Although agriculture is prominent, the number of households directly engaged in agriculture related activities is only 20.12%. Unemployment is high compared to the national rate of 4.9% (Labor Force Survey, 2010-Department of Census and Statistics) which could be attributed to the slow growth of agro based industries and lack of employment opportunities. Unemployment is high because the majority prefers white collar jobs in view of their higher educational attainments. On the other hand the expansion of the economy after the end of the war has not effectively reduced unemployment. At the same time due to the prevailed unstable political situation forced a transformation of the agrarian economy into a survival service economy and has failed to generate adequate employment in the area. It is noted that 31.96% of the population constitutes students and children below 5 years. 112. 6.8% of the population are employed in the public and private sector and receive a regular monthly income. Housewives represent 9.76% of the population and their contribution is not remunerated. Few of them are engaged in home based industries or wage labour for supplementary family income but not indicated under occupation. 113. Except for the owner cultivators, the earnings of the agricultural workers are meager causing them to fall into the poor category. Disruption of traditional agriculture and low productivity has led many farmers to abandon agriculture for a number of reasons e.g: • Massive displacement of population • Laying of landmines in agricultural lands • Absorption of agricultural lands into high security zones

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114. Consequently this situation has prevented many poor households to improve their financial status and has reduced the population to extreme poverty in the division. 115. The ownership assets of the sample of the affected population is shown in Table 55

Table 55 : The ownership assets of the affected population.

Ownership Numbers Car/Van 5 Bicycle 81 Motor cycle 39 Tractor 12 Lorry 1 Water pump 38 Gas cooker 15 Video 34 Refrigerator 28 Radio 53 TV 53 Source: Resettlement Plan for Vavuniya, 2012 116. Bicyclesare the main mode of transport in the area followed by motor cycle. Ownership of automobile is very low. However 6 affected households own car or van or lorry and they expected to provide the vehicles on hire basis to the project. TV has replaced the radio for entertainment and it is available among the low income families too. Few households own luxury items such as motor, gas cooker and electrical appliances. Since the Affected People are engaged in agricultures 12 own tractors and 38 own water pumps. 117. Table 56 shows the sources of income of the affected populations.

Table 56 : Sources of income of the affected population.

Source of Income Percentage of families

Agriculture 34.00 Livestock 10.00

Wage 12.75

Salary/Allowance/Pension 12.75

Remittance (Foreign/Samurdhi/donations) 6.00

Rent (land/buildings and other properties) 3.35

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Trade/Business 8.00

Non Farm products (household products) 2.00

Fishing 0.60

Renting heavy vehicles (Bus/lorry/trucks/tractor) 2.00

Renting light vehicles 1 (Van/car/land master) 0.67

Renting light vehicles 2 (Boat/3 Wheeler) 0.67

Interest (money lending/bank deposits) 00

Trees/Gardening 6.70

Source: Resettlement Plan for Vavuniya, 2012 118. Table 56 indicates that Most of the families earn an income from more than one source and the wage labour category is changing their occupation according to the season. Obtaining income information from individuals and households is a difficult task as many people were reluctant to disclose and often underreport. Therefore, to ease the field work, which is the most challenging activity of the survey, and to gather more accurate and reliable data, income information of the household members were collected individually at different levels and sections tactically arranged in the survey questionnaire. 119. Table 57 shows the monthly income of the affected persons.

Table 57 : Total monthly income of the affected persons

Income Level % Rs.50000 7.9 Source: Resettlement Plan for Vavuniya, 2012 120. Most Affected Peoples’ households get substantial income from their current occupations. The poverty level of the households falls into the first income category of less than Rs. 5000 and followed by the second category. Both comprise 19.73% of the population. 50% of the affected households are included in the well off income group of more than Rs. 20,000. Owner cultivators receive an income above Rs. 10,000. Those in business and the executives earn a monthly income of more than Rs. 15,000. Families having several employed members

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir and the remittances from family members employed abroad contribute largely to the family income. 121. The mean household income (average monthly) of the affected household stands at Rs. 25,306. It is below the national and district average of Rs. 36,415 and 39,640 respectively. Mean per capita income of the affected household (Rs. 5,840) is also below the national (Rs. 9,104) and district (Rs. 8,988) figures. (Household Income and Expenditure Survey 2009/10 of the Department of Census and Statistics). 122. Table 58 shows the pattern of expenditure of the affected families. It is an indirect way to get the real income level of the affected persons.

Table 58 : Pattern of expenditure of the affected families

Item of expenditure Percentage of families

Food 100 Clothing 100 Water 57 Firewood/Gas/Electricity 80 Dwelling house and other accommodation 11 Fuel for vehicles/boats/agricultural equipment 76 Medical health 100 Education 86 Equipment/inputs (household utensils) 82 Communication/transportation 91 Debt payment/interest 62 Social obligations 61 Religious functions 93 Smoking/alchohol/chewing betel 67 Maintenance cost of household structures and 72 equipments Charges for society membership scheme and 86 insurance policies Entertainment 57

Source: Resettlement Plan for Vavuniya, 2012 123. Table 58 reveals the expenditure patterns of the Affected People and it is obvious andinevitable that all the families need to spend for food, clothing and medicine. The important staple food is rice and curry supplemented with purchased other commoditiessuch as wheat flour, noodles, fish, meat sugar, vegetables and fruits. 124. Table 59 shows the types of livestock owned by the affected people.

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Table 59 : Livestock owned by the affected people

Poultry Cattle Goat 38 % 39% 3% Source: Resettlement Plan for Vavuniya, 2012 125. About 80% of the affected households are keeping livestock. Particularly cattle and chicken provide an additional source of food and cash income to a number of households. Relatively few households own goat. The demand for mutton and chicken is high in Vavuniya because of limited local supply. Poor slaughtering, processing and storage infrastructure hamper the market contribution of local producers.

4. Present water supply and water uses 126. The paddy land that will be inundated received irrigation water from three minor to medium irrigation Reservoirs namely Oodavy Sinnakulam, Periyakulam and Paranatakkal. The uplands were provided water from water pumps and also natural rain. Table 60 shows the availability of water in the sample of the affected communities for a variety of purposes.

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board

Table 60 : Availability of water for the affected people for different uses

Source Purpose Drinking Cooking Washing cloths Bathing Sanitation Agriculture Home garden House connection 5 0 5 5 5 0 1 Garden tap 0 0 0 0 0 0 2 Stand post (common tap) 1 0 1 1 1 0 0 Protected common well 9 10 9 9 9 0 2 Unprotected common well 4 5 5 5 5 0 0 Protected private well 36 41 47 47 47 7 23 Unprotected private well 3 2 4 4 4 0 0 Tube well 8 9 2 2 3 0 1 River 0 0 0 0 0 1 0 Steam/Spring 0 0 0 0 0 0 0 Canal 0 0 0 0 0 0 0 Rain water 0 0 0 0 0 17 3 Village tank 0 1 1 1 1 24 1 Source: Resettlement Plan for Vavuniya, 2012

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127. Most of the households have protected masonry wells for domestic as well as drinking water purposes. As a result most of them can access to water less than 50-m distance and within 5 minutes. For agriculture purposes particularly for paddy cultivation, the cultivators use Reservoirs. For home gardens and highland cultivation they use well water or lift irrigation from the river. The people feel that the well water is reliable for drinking with mixing chlorine or boiling. Only 5 households have NWSDB connections and their houses are in Vavuniya town.

5. Culture and historical aspiration of the affected people 128. Since the inundation area is predominantly rural and retains strong elements oftraditional culture based on religious, traditional and social value systems. Thesecharacteristics have made the people leading peaceful and harmonious lives. Consultationswith the people and officials reveal that a particular community called ‘Pandari’ communityis predominant in the area. One of the command areas which will go under water for theconstruction of the reservoir is called Pandara Periyakulam area. The remaining portion of theReservoir bed of Pandara Periyakulam Reservoir could also be converted in to paddy land for alternativeland option as per the request made by the Affected People. It is estimated that there are 10families belonging to Pandari community. This mitigation measure will pave ways to preservethe cultural heritage of the said community and feel them to staying in their traditionalancestral land.

6. Existing infrastructure facilities. 129. The area that would be inundated due to the reservoir and the adjoining water treatment plant had been predominantly under forest land use except for the paddy lands and upland cultivated sites. The area is very rural and served only by village roads and cart tracks. The village adjacent to the site of the proposed water treatment plant is served with grid electricity. There are no water supply schemes and the source of water is from wells or river. There are no schools or hospitals in the would be inundated area.

7. Reported environmental incidents 130. Table 61 shows the socio environmental incidents reported prevailaing in the affected area during last few years as reported by the community.

Table 61 : The socio environmental problems prevailing in the affected area

Environmental Incidents Incidents Reported % Human elephant conflicts 48 23.5 Snake bites 45 22.1 Illicit felling of timber 24 11.8 Dust related health problems 15 7.4 Water scarcity 19 9.3 Poor water quality 20 9.7 Solid and liquid waste dispos 12 5.9 Water borne Diseases 12 5.9 Illicit liquor 9 4.4 Total 204 Source: Resettlement Plan for Vavuniya, 2012 131. Snake bites and human-elephant conflict are relatively high in the area. Illicit felling of timber also stands 31.5% as the surrounding area covered with thick vegetations. Water scarcity is also recorded 25% because paddy cultivation requires adequate water.

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IV. ANTICIPATED ENVIRONMENTAL IMPACTS

1. The impacts of the proposed project activities on environment, both physical, biological and human, were studied in detail as per CEA TOR of the EIA. All impacts were analyzed with respect to pre-construction, construction and operation phases of the selected alternatives. Impacts identified for the whole project includes an assessment of the proposed reservoir project. Adverse impacts are mainly expected during construction phase with fewer impacts during pre-construction and operation phases. Most of the significant impacts identified for operation periods are positive ones. A. Impacts on soil and topography 2. The reservoir construction will change the present land use of an area little more than 250 ha identified as the project area and that includes sites for the treatment plant and for housing the logistics of construction. Presently the land cover is predominantly forest (Dry Monsoon Forest, Open & Sparse lands) and water bodies. As the purpose of the reservoir is to supply drinking water, all the vegetation has to be removed. A large number of mature trees which belong to the genera Terminalia arjuna (Kumbuk), Manikara hexandra (Palu) and Drypetes sepiaria (Weera) and a few others, has to be uprooted. The mature trees of Kumbuk takes up lots of space and the task of uprooting these is difficult and cumbersome and would cause much disturbance to soil. The soil type is Reddish Brown Earths and it is more prone to erosion depending on the steepness and vegetation type and density. 3. Besides land clearing, soil erosion and compaction are expected due to heavy earthworks and heavy machine operations during the construction of the bund, spill and associated structures. However, the impacts of land clearing is expected to be less in the treatment plant site as it has already been used for upland cultivation several times. In stream work can also dispatch sediment in downstream areas of Per Aru river if not managed properly. Magnitudes of these impacts are expected to reduce once the construction period is over. B. Impacts on hydrology and water quality

1. Changes in surface water flow 4. During the construction of the bund, natural water flow and natural drainage paths will be obstructed. Further, the extensive excavations with heavy machinery will cause sedimentation in nearby water bodies. These impacts would prevail only during the construction phase. 5. In spite of the fact that Per Aru is a perennial river, heavy water flow is expected during the months of December and January while the dry months (July to August) the flow will be reduced drastically. There is hardly any flow during the month of August. The seasonal natural flushing of the river will occur in the river with the onset of North East monsoon rains in the month of October. Thus, rain is important as a measure of self- cleansing the river and also for sustaining its fauna and flora. The reservoir will control the natural peak flows towards the downstream of the river during wet weather and the river overflow will not occur. Downstream of the river section will not be completely dried up because of the environmental flow which will be released throughout the year. Impacts such as disruption to regular stream flow from surface runoff will cause an increase in sedimentation on the river bed at the immediate downstream of the dam.

2. Changes of groundwater table 6. The groundwater level will rise in the areas in the vicinity of the reservoir. Rise in groundwater table around the reservoir can destabilize the soil formations to a certain

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir extent. Yet due to the area being rather flat, the magnitude of this impact will be comparatively small. Impoundment will not cause lowering the ground water table l during the dry months. There are rock bands across the river at regular intervals. The test results indicate that the underneath porous soil strata cannot disrupt the seepage paths and will reduce the negative impacts on groundwater recharge. The presence of an alluvium in the bottom reaches of the river will help holding water for longer periods.

3. Favorable aspects of impoundment 7. The water resource will be stored in the reservoir for the intended uses. The year round availability of water will ensure uninterrupted drinking water supply. The presence of the reservoir will positively influence the micro climate and will enhance the aesthetic beauty of the area. The ground water level in the immediate periphery will be increased. The reservoir is bordered by the the southern edge of the jungle corridor proposed in the Integrated Strategies Environment Assessment Report 2011. Therefore the reservoir will be a source of water for the wild animals and thus it will prevent elephants moving into villages in search of water during the dry months.

4. Water pollution due to machinery and site activities 8. Construction of the dam will go on for about 30 months. Soil erosion will occur during this period, and will increase during the rainy season of October-January. At every location that involves earthworks, there will be induced soil erosion. The eroded soil will be carried to the river with the surafce runoff resulting in the short term an increase in sediment loads and turbidity. Wastewater discharged from construction activities may include: domestic wastewater discharges from labor camps, water used in construction processes, contaminated storm water runoff from accidental spillage construction equipments and possible chemicals stored on site. 9. During the construction period human activities in the project area and its surroundings will be increased due to increased number of workers, and their service providers. This will increase the domestic wastewater discharge. General house keeping if not maintained will be noticeable and can deteriorate aesthetics of the area. 10. Use of water for construction activities will produce contaminated water from material depots, workshops, vehicle washing areas and concrete swills. Oil and grease, leachate from construction materials are potential pollutants in the project areas. Escaping of chemicals, human waste can result in poor quality of surface water that may cause health problems to site workers and and any potential user residing in downstream areas.

5. Impacts on surface water quality (operation phase) 11. The sludge from the water treatment plant, if not properly disposed, will contaminate surface water bodies and also ground water and soil. This sludge will have residuals of chlorine, alum etc., which will create a low pH in the waters and make it unfavourable for both fauna and flora. C. Impacts of air pollution 12. Air pollution can occur when substances (air stressors) in sufficient quantities is discharged in the surrounding atmosphere which can cause harmful effects on human, animals, and vegetation. During the construction period, air pollution can occur due to construction activities. The impacts resulting from air stressors such as small particulate matter (dust) and harmful gases (SO2, NO2, CO, ) are expected to emit from earthworks, exhaust fumes, dust from exposed surfaces, rock blasting and increased traffic. 13. Further, depending on the weather conditions burning and other site preparation activities may deteriorate air quality in nearby villages.

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir D. Impacts of noise and vibration 14. The impacts due to noise and vibrations are expected to be most severe during the construction period. Construction noise and vibration varies greatly depending on the construction process, type and condition of equipment used, and layout of the construction site. For most construction equipment, the engine, which is usually diesel, is the dominant noise source. Table 62 illustrates the typical noise levels measured at distances of 15 m and 30 m from the noise generating construction equipment used in various stages of construction.

Table 62 : Typical values of noise produced by common vehicles and equipment

Equipment Maximum noise Leq exposure at 15 Leq exposure at 30 level at 15 m from m from source / m from source / source / dB(A) dB(A) dB(A) Auger drill rigs 85 82 76 Telescoping boom 81 71 65 bucket trucks

Front loader 80 75 69

Dump truck 71 63 57

Concrete truck 82 79 73

Vibratory hammer 85 82 76

Diesel construction train 77 58 52

Generator (night time 85 70 64 lighting)

Pneumatic drill (in 81 80 74 concrete)

Utility truck (with crane) 78 76 70

Flat bed truck 81 68 62

Computer 81 75 69

Dozer 85 82 77

Hammer to drive rods 86 80 74 (small vibrator)

Backhoe 80 75 69

Wood saw to construct 88 82 76 forms

Forklift 80 74 69

Source: ITI Report No. SS 1113352 (2011)

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15. Apart from the operation of equipment on site, noise and vibration will also be emanated during transportation. Soil requirement will be sourced from the project site, and other construction materials (i.e. cement, steel, rock, sand, ready mixed concrete, bricks) will be brought from outside during the construction period. Waste soil, while making the full effort to reuse, will be transported for dumping. If the roads are damaged due to the increased traffic they will increase the noise and vibration impacts on the environment. As there are no houses in the immediate vicinity of the construction site (there are 03 temporary houses within 100-m from the reservoir but will be relocated as it is the designated buffer zone), the impact of noise and vibration on inhabitants can be considered as nil. According to the Regulation 4 of Gazette Notification No 924/12/1996 on noise regulations, the allowable limit for day time operation during the construction phase is 75 dB (A) while it is 50 dB (A) during the night. During the operation phase, the day time operation limit is 55 dB (A) and the limit for night time operations is 45 dB (A). Table 63 shows the types of equipment/ machinery/ vehicles that would be used during the construction of the project.

Table 63 : Types of equipment/machinery/vehicles for construction

Machinery / Equipment /Vehicle Quantity of operation

Crawler Tractor (80 – 120 Hp) 1 Crawler Tractor (180 – 200 Hp) 2 Crawler Tractor (300 Hp) 1 Sheep foot roller ( Twin drum ) 1 Motorized Scraper (14/20cu.yd ) 3 Motor grader 120 – 150 Hp 1 Hydraulic backhoe excavator (1cu.yd) 1 Rear dumper (15 Tons) 4 Water browser (1200gls) 2 Mobile crane (10 Tons) 1 Air compressor (300cfm) 2 Pneumatic jack hammer 2” 1 Front end loader ( 2.5 – 3.5 cu.yd) 2 Concrete mixer ( 14/10 cu.ft) 2 Concrete mixer ( 5/7 cu.ft) 2 Pneumatic vibrator 2” 4 Tractor (60Hp) 2 Lorry (3Tons) 2 Front end loader ( 1.5 – 2 cu.yd) 2 Rear dumper (5 cu.yd) 1 220 Hp crawler hydraulic excavator ( 2 ‐3 cu.yd) 1 Submersible pumps for Intake at Puthukulam 1 Horizontal split casing pump for ground sump 1

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End suction vertical delivery for WTP to WTP 1 Source: ADB 5 Project of NWSDB 16. Table 64 shows the assessment of the noise modeling data for both construction and operation stage in the four locations of the project site.

Table 64 : The assessment of the noise modelling data

GPS Locations Existing Noise level Predicted Noise levels dB(A) day/night dB(A) Scenario 1: During Scenario 2: Construction During Operation 401153.17 mN 38 45-50 40-45 165720.97 mE 401634.88 mN 41 55-60 50-55 164911.33 mE 402196.58 mN 41 45-50 40-45 164158.48 mE 402465.09 mN 33 40-45 35-40 166646.69 mE

17. According to assessments in Table 64, the noise and vibration emnating from works during the construction as well as operational phases do not exceed the allowable maximum limits which are specified as 75 dB during day time operations of construction (06.00 – 21.00 hrs) and 50 dB during night time (21.00 – 06.00). Thus, noise impacts will be insignificant. E. Ecological impacts

1. Impacts onterrestrial fauna and flora due to habitat losses 18. The total area that would be inundated due to the reservoir is 250.5 ha of which 168 ha is forest comprising riverine forests on either side of the Per Aru River, dry monsoon forests and scrub forests. The rest comprises areas used for perennial agricultural lands and water bodies. Riverine Forests are extremely important and represents rare ecosystems in the country. Riverine forests, particulaly those in the downstream can potentially be threatened by reduced water flow in the downstream afer the completon of the impounding reservoir. 19. Forests in the project area provide habitats for many endemic and indigenous species among the variety of plants and animals in the project area. Among the plant species that will be lost, there are 279 species in total including 92 trees, 25 shrubs, 95 herbs, 4 ephiphytes, 63 climbers/creepers. Among the endemic species, 7 were observed in river and riverine habitats while 8 were observed in the dense forests. Four endemic plants were observed in degraded forests while another 4 were observed in open scrublands. In tanks and associated vegetation 4 endemic species were found. There were 2 endangered species (Cryptocoryne beckettii and Diospyros ebenum) in River and Riverine habitats, one in dense forest and another in tanks and associated vegetation. There are four vulnerable flora species: Stenosiphonium cordifolium, Margaritaria indicus, Vanda tessellate, and Mitragyna parvifolia. Out of the vulnerable species listed 2 each were seen in River and Riverine habitats (Margaritaria indicus and Vanda tessellate) and forests (Stenosiphonium cordifolium and Mitragyna parvifolia) while three (Margaritaria indicus, Vanda tessellate, and

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir Mitragyna parvifolia) were found in tank and associated vegetation. Open scrublands also recorded one vulnerable species (Mitragyna parvifolia). 20. While most of the above mentioned species are also found in other similar habitats in Sri Lanka (ie. Bu Nelu, Kaluwara, Mallotus repandus, Karawu, Wal kahabiliya, Vanda Orchid, Helamba) the aquatic species Ati Udayan (Cryptocoryne beckettii) which occurs in the river and riverine areas is an endemic species which is already endangered. It is also not widely seen in other similar habitats. Among the flora which will be inundated by the project, species of ecological, medicinal and other human use values are present. Apart from being useful for humans, they also sustain many fauna i.e. elephants and other herbivores, bees, monkeys, squirrels etc. Although not high in biodiversity, many paddy fields house medicinal plants in the locality. 21. The high diversity of plants in the area supports diverse groups of animals by providing food and habitats. A total of 316 faunal species were identified in the study area among which there were 28 endemic species, 3 proposed endemic species, 3 critically endangered species (Mycalesis visala, Euplecta colletti and Japonia vesca), 1 endangered species (Theobaldis subplicatulus), 11 vulnerable species (one bird, two butterflies, 6 mammals, and two reptiles) and 19 nearly threatened species. 22. Feeding and nesting grounds of reptiles and mammals will be disturbed and dislocated. These animals will try to escape to safer localities, especially those in the upstream. The situation in the upstream would also increase the encroachment of the territories of inhabitants of such areas. Such circumstances could create inter population and intra population conflicts among the faunal populations. 23. The reservoir lies in a migratory route of both herbivorous and carnivorous mammals including elephants (dung were noticed in the biotic survey). Based on the data on mobility of animals, this area had been identified as a Jungle Corridor by the Department of Wildlife Conservation. During the dry season of the year many animals visit Per Aru for water. All these animals will be greatly affected by the project either permanently or temporarily if no proper precautions are taken to avoid such situations.

2. Impacts on aquatic fauna and flora due to the project. 24. In total, 117 floral species were observed. Among them 7 endemics, 2 endangered species (Cryptocoryne beckettii and Diospyros ebenum) and 2 vulnerable species (Margaritaria indicus and Vanda tessellate) and three exotic species were present. There were 21 types of fish observed in the river. Out of them were 3 endemics and one nearly threatened species (Climbing perch). The construction of the reservoir will inundate riverine/aquatic habitats as it will be converted to a stagnant water body. When the area is inundated the height of the water column will be high, and that would create the following physiochemical changes in water. • Stratification of the water column would affect the desired levels of the following variables: a. Dissolved Oxygen (DO); b. Salinity; c. Conductivity; d. Temperature; • Nutrients – The reservoir would undergo initially tropic upsurge and then tropic depression before reaching a stable state. 25. Since this reservoir is located within the Dry Zone of Sri Lanka, high amount of evapo-transpiration will take place. However, the water quality of the Per Aru shows that the conductivity is about 393 us/cm, which is within the safe limits but not a low figure compared to waters of other basins i.e. Kalu Ganga in which the conductivity ranges between 40-80

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir us/cm and in Amban Ganga the conductivity is more than 100 us/cm (EIA Study on Kaluganga Agricultural Development Project, 2007). 26. According to the past studies on reservoirs in Sri Lanka many of them experience anoxic conditions at the bottom. This condition is detrimental to aerobic organisms including fish. Similar condition also can be expected in Per Aru reservoir if proper designing is not done to circulate the water column. 27. When considering the reservoir ontogeny, all the reservoirs undergo trophic upsurge soon after the initial inundation. This happens when the nutrients of the top soil get dissolved in the water. 28. Collectively all these circumstances would be detrimental to any kind of aquatic organisms including fish. Further semi-aquatic organisms such as amphibians also would get affected since they are known to be sensitive to environmental factors. 29. The dam will create a barrier, which will impede on fish migration patterns. A fish ladder is incorporated to the final design of the reservoir.

3. Impacts on nearby forest reserves (if any) 30. There are no forest reserves in close proximity of the reservoir. The two forest reserves i.e. Mel Kulam Forest Reserve and Rasenthrikulam are outside the perimeter of the reservoir.

4. Impacts on nearby wildlife reserves and wildlife migration 31. There are no gazetted wildlife reserves in the proposed location. As already described, there is a proposal to establish a jungle corridor, as shown in Figure 30, in the recently concluded Integrated Strategic Environmental Assessment (ISEA) for the Northern Province. The jungle corridor has been proposed with a view to connecting Padaviya Proposed Forest Reserve and Giant Reservoir Sanctuary. As shown in Figure 31, a part of the proposed reservoir is located at the southern boarder of this proposed corridor therefore the reservoir will not obstruct the corridor path. 32. During the construction phase there could be disruption to the wildlife and their migratory routes, but once the reservoir is constructed and operating, gradually nomalcy will prevail and positive impacts will become apparent from the availability of water in the area.

5. Impacts on wetlands due to changes in water balance 33. Per Aru meets Turumpamaddai Aru at distance of about 08-km from the location of the dam. There are no designated wetlands identified along this stretch and no impacts are anticipated on wetlands.

6. Risk of invasive species 34. Disturbances due to the construction of the reservoir project could contribute to the introduction and spread of exotic invasive species both aquatic and terrestrial. Further, after the construction, the physical and biological properties of the reservoir can potentially make the surroundings more prone to be invaded by exotic species. Reservoir construction typically replaces varied stream habitats with mono-culture habitats and more laden with suspended solids and dissolved solids. Moreover, they typically contain unstable, recently assembled communities of stocked fish. These characteristics enhance the susceptibility of reservoirs to invasion. 35. There are number of invasive species both flora and fauna in Sri Lanka. The ones that are associated with reservoirs and streams are Salvinia (Salvinia molesta) introduced to Sri Lanka in the late 1930’s, Water hyacinth (Eichchornia crassipes), introduced to Sri Lanka

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir due to its horticultural value, Mimosa pigra (Giant sensitive plant) recently identified as growing luxuriantly in the riverbanks of the Mahaweli River. 36. Among the invasive faunal species reported in connection with reservoirs in Sri Lanka, Chitala chitala (Clown Knife fish) a well known large voracious carnivore who feeds on slow moving indigenous fish, Hypostomus plecostomtis (Tank cleaner), a species imported to the country by the ornamental fish industry, and Sarotherodon mossambicus (Tilapia) introduced to the country’s aquatic systems as source of protein. It shows non selective feeding habits and prolific breeding enabling it to colonize reservoirs, small tanks and slow flowing rivers. Therefore, promoting aquaculture had caused losses in biodiversity.

7. Impact on threatened species and biological diversity 37. The Biological survey was conducted from November 2010 to April 2011. The results of sample study survey is described in Chapter 3. 38. Plant species that will be lost due to inundation are 279 species in total including 92 trees, 25 shrubs, 95 herbs, 4 ephiphytes, and 63 climbers/creepers. Among them there are 2 endangered, 4 vulnerable and 3 near threatened species. 39. A total of 316 fauna species found in study area and the upamong which there were 28 endemic species, 3 proposed endemic species, 3 critically endangered species, 1 endangered species, 11 vulnerable species and 19 nearly threatened species. 40. A separate biotic survey has been carriedout up to Mamaduwa reservoir in the upper catchment as described in section 3 of the Chapter III.There were 04 endangered and 07 vulnerable fauna species out of 263 fauna species found in the upper catchment. Among 695 flora species found in the upper catchment there were 01 critically endengered, 01 endangered and 05 vulnerable flora species. 41. The Project will cause some adverse impacts on aquatic species as the dam will transform part of stream into a lake. A total of 21 fish species were recorded in the biotic survey and of which no threatened fish species were found.. 42. The project will have adverse impacts on biodiversity since species including endemic and threatened will be lost due to habitat loss and fragmentation, although all endangered species are commonly found in the forest area adjacent to project dam site, as well as in forest areas in Vavuniya District. F. Sociological / cultural impacts

1. Impacts on existing water usage/ extraction/irrigation schemes 43. Due to the construction of the reservoir, there will be less water in the downstream areas. The river is rarely used for bathing and other human activities as there are many irrigation reservoirs in the downstream which are used for both agriculture and human activities. 44. The paddy is cultivated with irrigated water from existing reservoirs together with rainfall during the wet season. During the dry season mix cultivation is practiced with the available water in the reservoirs. Paddy cultivation will be limited. As shown in Figure 4, none of the existing reservoirs located at the immediate downstream of the proposed reservoir are fed by the Per Aru waters, and therefore the impact on existing water use is insignificant.

2. Relocation of affected people 45. There are no permanent houses in the inundated area other than to 3 temporary houses in the buffer zone area, which will have to be relocated

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir 46. While they are illegal dwellings people residing in these dwellings will experience impact on their lifestyle.

3. Change/disruption of life style 47. The main source of income in the affected farming community is agriclture and to a lesser extent livestock farming. There will be impact on 102 ha of agricultural land imposing economuic displacement of 107 affected person. 48. Due to the construction of the reservoir, the existing access road to the village beyond the Per Aru will be lost. In its place, a new access route will be developed around the dam. In addition to this, there would be a footpath on the dam too.

4. Change in land use pattern 49. 168 ha of forests in the categories of riverine forests, dry monsoon forests and scrublands, 60 ha of agricultural lands and 1.5 ha of water bodies will be inundated by the reservoir. Existing green land cover will be changed to a waterbody. Impacts of changing the land use will be significant as far as loss of habitats of fauna & flora species are concerned.

5. Impact on quality of life 50. Due to the provision of much needed constant and reliable source of drinking water the Project will improve the quality of life of many people especially those in the 21 GN Divisions who are the targetted population to receive the supply of water. Further, in the resettlement plan proposed by the NWSDB, all the affected communities will be compensated adequately. 51. The project-affected families are mostly rural, and many of them depend on agriculture for their livelihood. Unemployment is high (20%) among them and could be attributed to slow growth of agro-based industries and the lack of employment opportunities in the area. 52. Ninety three percent of the affected families are Tamils. The remaining ethnic groups are Moors (5%) and Sinhalese (2%). Majority (78%) of affected families are nuclear families, and 22% are extended families. There are 34 vulnerable households among the affected families including 13 female-headed families. No family will be physically displaced because of the sub project. It will however affect 03 temporary houses (huts), 06 masonry wells, 05 ground water wells, and 01 Hindu kovil (temple). 53. The subproject will impact on cultivated lands causing imposing economic displacement of to 107 families. The inundation area of the proposed reservoir and the 100- m buffer zone around it cover 102 ha of land of which 79 ha are paddy land. On the remaining land of 23 ha, farmers cultivate seasonal crops under chena (slash-and-burn) cultivation method. There are 130 claimants to these lands either sole or joint land users. They are members of the affected 107 families. Nineteen percent of claimants possess land title deeds, while 17% hold 'cultivation permits' from the Government. Another 3% received land grants or “Jayaboomi” deeds from the Government. 24% of claimants are registered as 'cultivators' at the Agrarian Service Center. The other claimants (37%) do not have any documents to show their rights over the land they possess and cultivate. The Resettlement Plan 2012 of the subproject indicates that 54% of the claimants have been cultivating the land for more than 25 years, while 9% have started cultivation within the past 5 years. The project authorities will provide land for claimants under the land-for-land compensation package.

6. Employment generation during construction and operation 54. A large number of new employment opportunities will be created during the construction period. Opportunities for direct employment will be created in the construction

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir activities alone. There will be even many indirect employment opportunities for skilled categories such as masons, carpenters, bar benders, load counters. There will be an inflow of labour from areas outside Vavuniya as well as from the locality for unskilled labour categories. The expected labour inflow during the peak construction period is expected to be quite high. Therefore, the influx of labour from the outside will easily outnumber the local residents.

7. Impacts on historical, cultural and religious significance 55. The only building of historic, cultural or religious significance is the Hindu kovil located in the Periyakulam command area. This has been in existence for some time and the incumbent is very concerned that the kovil is not to be relocated. Therefore the kovil will be rebuilt at the same premises at a higher elevation.

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V. ENVIRONMENT MANAGEMENT AND MITIGATION

A. Mitigation of physical impacts 1. Measures to mitigate adverse effects anticipated in pre-construction, construction and post construction periods of the project are discussed below. Special emphasis has been given for the significant negative impacts identified by using the Leopold Matrix as the tool of analysis. These negative impacts are: Soil erosion and land degradation; Water Pollution, Loss of habitats including riparian and dry mixed evergreen forests, loss of biodiversity, loss of farmlands and loss of a religious site.

1. Land management

a. Soil conservation

2. The Reservoir will be built on land which has hitherto not been disturbed by development. It is under a predominant forest land use at present. The Water Treatment Plant will be built on land presently being cultivated with other field crops. Construction of the reservoir and the water treatment plant will warrant extensive site clearing, uprooting of a large number of mature trees, use of heavy machinery etc. 3. The negative impacts, especially soil erosion during the rainy season, will be high during the construction phase. Though the construction would commence in a dry weather period, work will not be completed before the onset of monsoon rains. Formation of soil conservation bunds along contour lines will help preventing sediment being transported with surface run off. Flat topographical terrain over the downstream area will help lower the surface runoff velocity. Soil conservation bunds can be formed by using top soil material which will be removed prior to commencing the construction activities. Other hard material removed from the excavation such as weathered rock, which is not used as a construction material, will be used to strengthen the conservation bunds. 4. As an alternative to mechanical soil conservation methods, biological soil conservation methods by using trees and grass sedges can also be used in preparation of land for cultivation in the resettlement sites. Gliricidia (Gliricidia sepium), Vetiver (Vetiveria zisionoides) and Citronella (Zymbopogun nardus) hedges can be introduced to control soil erosion. These plant species are locally available. Purpose of this practice is to improve the physical tilt of the soil, maintenance of the soil nutrients level, suppress weeds, which are difficult to control and to reduce the evaporation demand by maintaining a low temperature and high humid micro-climate over the ambient crop layer. 5. Soil required for the reservoir bund will be procured from the reservoir bed according to the guidance provided in the Report on the Soil Investigation conducted by Soil Tech Ltd in 2011. The other construction material will be brought from outside from licensed quarries, thus minimizing the damage to local soil and environment. If these material are left open, erosion could be caused by winds and may blow away the particles of soil when the soil is finely divided and bare, the surface loose and dry, and the winds are strong. To mitigate such impacts it is necessary to keep the piled up soil moist or covered as far as practicable. Water should be sprayed as required and practicable on the soil. Care should be taken to avoid spraying in excessive volumes as that may cause surface erosion. The loose soil and other loosely piled up soft construction material need to be covered with tarpaulin. 6. Construction of earth dam is one of the major components of this project, which would take a long time for full completion. Two of the final activities connected with construction of the bund, are turfing the downstream slopes and rip-rap protection to the

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir upstream for protecting the dam slopes from being damaged due to soil erosion and forming of runnels. It is proposed to arrange these two activities prior to onset of rainy season without waiting till the dam construction is over. 7. Existing access routes will be used as much as possible during the construction. New access roads will be built only if they are an absolute necessasity. In the event these are inevitable, they will be removed soon after the construction is over. To avoid soil erosion, surfaces of all temporary roads need to be compacted with a thin layer of gravel.

b. Drainage Mangement

8. Especially in the dry zone areas, there exists natural water ways, which are activated only during the rainy seasons. During construction utmost care needs to be taken to maintain the existing surface water drainage paths without blocking. If this cannot be avoided alternative drainage paths have to be constructed to facilitate such natural drainage. When the construction work is being executed close to water bodies, sediment traps or sedimentation ponds should be constructed at regular intervals. Buffer zones of undisturbed vegetation should be left between work sites and water bodies. During the construction phase, it is required to clean all drainage canals at regular intervals.

c. Reinstatement of burrow areas

9. Burrowing earth in existing quarries could cause environmental impacts but it will be ensured that excavation are not steep. Permanent slopes left behind shall be finished to flatter slopes than that is required for slope stability. Such slopes shall be covered with at least 300-mm of top soil to encourage vegetative growth to blend with the surrounding. 10. At the bottom of the quarry all depressions shall either be drained or filled with at least 300-mm of top soil available from excavation to prevent stagnation of water as well as to encourage vegetative growth to blend with the surroundings.

d. Utilizing removed material

11. Areas at close proximity to the work sites need to be located for dumping rock and soil generated during construction. As much as possible Contractor shall reuse the soil produced in excavations in permanent work if the material conforms to the required quality standards. Other construction debris shall be buried to minimize impacts on environment. All material dumps should be maintained in a manner for preventing slipping and erosion.

e. Operations by the contractor

12. Areas, where facility construction will be carried out, need to be cleared of vegetation. In such areas all trees, saplings and shrubbery should be protected from unnecessary damage by contractor’s operations. The natural landscape should be preserved to the extent possible by conducting operations in a manner that will prevent unnecessary destruction or scarring of the natural surroundings. 13. Removal of vegetation outside the reservoir area should be limited to the bare minimum. As the area extends beyond the work space only the secondary growth should be removed leaving all trees above a girth of 30-cm without damage.

f. Precautions during a flood

14. Flooding during the rainy season will affect the construction activities. Threat of earth dam being breached at the river section and at eiher side of the river bank, possible damages to temporary river diversion canal, and downstream treatment plant would have to be minimized by strategic planning interventions. Coffer dams need to be provided across

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir temporary river diversion and around river section dewatering pits. Coffer dams will minimize damages as they are temporary structures, which would breach during a severe flood without letting to cause upstream flooding. Temporary labour camps, site offices, machinery yards, and workshops should be located on the left bank of the river to avoid crossing the river during a flood.

g. Situation management at near structural failure

15. Weir failure without early warning signs is a high risk in a sever flood. The reservoir is designed after considering a 100 year history of floods in the area to ensure that there is only 1% probability of occuring a flood similar to the peak flood which had ever occured in the area during the last 100 years. However, there are 03 radial gates each with a width of 6-m for discharging flood waters into the river section. When the reservoir water level reaches the spill crest level, early warning actions such as announcing to downstream users, informing the public media, coordination with the disaster management centre of the area, obtaining reservoir controlling advice from the central Irrigation Department should be adopted. In the Irrigation Department and in the Mahaweli Authority of Sri Lanka, Dam Safety sub Departments are functioning. They have their monitoring stations in their offices established at all reservoirs within their purview.. The implementing agency, NWSDB, should obtain their advice and get the implementing staff and operatiing staff trained during all stages of the project. h. Downstream river course management 16. The project has made provisions for continous water flow which will be released from the reservoir for the downstream users and to portect the environment. As reported in earlier section of the EIA report, there are no legal water user at the downstream, who use the river water for agricultural activities. Further, the river is not being used for bathing, fishing or any other domestic activities as there are many minor irrigation reservoirs located much closer to the human habitates along the downstream. 17. About 08-km downstream from the bund, Turumpamaddai Aru tributary will join the Per Aru and within this stretch the river water is not diverted or tapped for any human activity. According to the Table 65, annual environmental flow (e-flow) volume is 2.6 MCM, which is 18.3% of the total inflow volume to the reservoir. The minimum environmental flow of water is to be released from June to September of the year at the flow rate of 0.038 cu.m/sec. The proposed e-flow has been determined based on a comprehensive study has been carried out to assess instream flow needed to sustain the ecosystem functions that native fish and wildlife species depend upon to survive and flourish. Environmental flow is planned to be released in a manner simulating the normal flow pattern of the Per Aru. The other inflows to the affected stretch such as rainfall runoff, over flow and drainage flow from upstream irrigation reservoirs were also accounted. The reservoir spilling water during the months of heavy rainfall (from November to January) flows through the river ensures that trigging and habitat maintenance flow requirements are met.

Table 65 : Reservoir inflow and environmental release

* Monthly *Monthly E- Uniform e-flow Depth of water over Month Inflow volume flow volume flow rate 100 m strip along river (MCM) (MCM) (m3/sec) banks (mm per day) January 2.25 0.4 0.153 8.3 February 0.19 0.3 0.115 6.2 March 0.74 0.3 0.115 6.2 April 0.30 0.2 0.076 4.1

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May 0.10 0.1 0.038 2.1 June 0.03 0.1 0.038 2.1 July 0.03 0.1 0.038 2.1 August 0.06 0.1 0.038 2.1 September 0.18 0.1 0.038 2.1 October 0.21 0.2 0.076 4.1 November 3.26 0.3 0.115 6.2 December 6.85 0.4 0.153 8.3 Total 14.2 2.6 *Source: Hydrological Studies for Per Aru Reservoir, 2011

18. The initial reservoir filling and surveillance plan should be prepared by the design staff. Initial filling should be well documented, including a record of reservoir elevation and controlled water releases during the filling. It is recommended to fix a guaging station at immediate downstream of the proposed reservoir and to calibrate the river section for monitoring the environmenntal flow released from the reservoir.

i. Waste management

19. As the said construction is across a river course, water is bound to get polluted by construction debris, loose soil, leakage from vehicles and machinery and also from worker camps. Some mitigation actions proposed, especially for construction work close to water bodies are as follows;

• Construct site offices away from stream and river banks and reservations.

• Ensure a regularly service & maintenance system for plant, machinery, and equipment.

• Storing fuel and lubricants under cover, away from water courses, on concrete or asphalted floors with impermeable liners and traps for accidental spills that could get into surface water. These should be away from water courses.

• Have contingency plans drawn up for possible spills and leaks before construction begins.

• Facilitate adequate drainage on site

• Prevent cement slag from polluting surface water.

• Install grit traps and gully gates to hold back the debris in surface drains.

• Educate labor gangs on the need to have clean water bodies.

• Introduction of waste disposal and management system within the project premises for all kind of waste material such as solid, liquid, oils & grease, plastic etc.. • All debris and waste from worker camps should be properly disposed in the identified dumping locations. Muck and other spoil should be placed in low lying

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir dry areas, but never in the river embankment where it will be eroded. Waste plastics should be sold or given to existing plastics collector in Vavuniya.

j. Maintenance of the treatment plant

20. Once the facilities are constructed water pollution will be very limited. However, an important source of pollution will be the sludge that will be disposed to the environment from the water treatment plant. For mitigation the following precaustionary measuers should be put in place; • The sludge beds should be placed slightly above the ground away from the drainage paths. • Sludge should be allowed to dry up before removal. • Sludge beds should be constructed in concrete to avoid sludge contaminants to seep into the groundwater. • As the method of treatment is conventional and the raw water quality of water is good, no serious odor problems are expected. • Sludge should not be disposed of with municipal solid waste or it will be used as fertilizer as is being done in similar plants of NWSDB. To minimize chlorine leakage and the resulting odour at the treatment plant, standard ventilation, fire protection facilities and chlorine storage facilities should be provided according to the specifications. • Special drain system should be designed to drain out the backwash water of the filters. 21. In preparation of bidding documents necessary conditions need to be included by specifying actions for mitigating the negative impacts on the environment, especially regarding transport of materials, borrow areas and quarries, construction of temporary buildings etc., so that the damage to soils and landscape could be minimized. Awareness programs shall be conducted for the contractors’ staff regarding landscaping and protection of the surrounding environment. Instructions need to be regularly issued since workers can change according to the type of the work program. 22. The natural landscape should be preserved to the extent possible for conducting operations in a manner that will prevent unnecessary disturbance of the natural surroundings. 23. Except where required for permanent works, quarries, borrow pits, staging and processing areas, dumps and camps, natural environment should be protected from unnecessary damage by the contractors’ operations. 24. Adherence to measures for mitigation of negative impacts arising out of the operations connected with construction should be made conditional in the civil works contracts. The contractors shall prepare their specific environmental mitigation plan according to the contract. The NWSDB will supervise the construction activities by employing construction supervision consultants and environmental monitoring consultants.

k. Compensatory afforestation program

25. Construction of the reservoir, will destroy about 168 ha of forests which includes 146 ha of dry monsoon forest (DMF), 18 ha of open & sparse forest (OSF), 4 ha of scrub forests (SF), as classified by the Department of Forest Conservation (DFC) and Survey Department. The riverine forest is clasified under the forest type DMF. Table 21, shows the loss of each type of forest cover as percentage of the total inundation area and as a percentage of similar

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir forest cover types within the study area. According to the Table 21, 67% of the inundation area is forest out of which 58% DMF, 7% OSF and 2% Sc type. 26. A tree survey conducted to estimates the losses revealed that about 1559 mature trees in the inundated areas would have to be uprooted or cut. According to the National Environmental Act No. 47 of 1980 a reservoir includes the inundated area plus 100 meters from full supply level (FSL) of the reservoir. Further, according to the recommendations of the Forest Conservation Department (FCD), an area similar to that would be inundated by the reservoir, would have to be replanted. 27. The area which does not fall under the standard forest types by the FCD is declared as “Non Forest”. According to topographical maps, there exist different land cover /land use types classified by the Survey Department within the so-called non forest area. They are scrub jungle, garden, paddy, water bodies and grasslands. These non-forest areas are available for afforestation as indicated in the Figure 33. Afforestation program will be designed on suitable land extend equivalent to the area of inundation. The areas for afforestation was selected by considering areas adjoining to the existing forest cover types which were similar to the affected forest cover types inside the inundated area. 28. In the inundation area, plant species, both trees and shrubs, that would be removed due to the construction of the reservoir, were listed and similar varieties were considered for afforestation with the view of restoring the vegetation that would be lost. A combination of plant species comprising indigenous/ endangered/ endemicplants, which are present in the dry monsoon forest, open sparse forest and scrub jungle plants with multipurpose value as well as specific values such as medicinal, fruit etc, were identfied for replanting. The list shown in Table 66 provides a guide for selection of species; The plant spacing should be 5m x 5m. 29. Plants species shown in Table 67 are recommended to plant between the trees which are planted in the overstorey. The spacing should be 2.5m x 2.5 m and this has to be intermixed with the trees. It is recommended to use as many species as possible from species available for replanting and most of the species are available in the natural forests of the area.

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Table 66 : List of proposed plant species for afforestation

Common Scientific name Common Scientific Commo Scientific name name name n name name Amberella Spondias pinnata Goraka Garcinia sp Milla Vitex altisimma Aralu Terminalia Guava Psidium Mora Dimocarpus chebula guajava longan Badulla Semicarpus nigro Halmilla Berrya Na Mesua viridis coridifolia ferrea/M. nagasarrium Bora Grewia Kalumedir Diospyros Neem Azadirachta daminiya helicterifolia iya oppositifolia indica Bulu Terminalia Diospyros Nelli Phyllanthus belerica Kaluwara ebenum embilica Chloroxylon Kaluwara Diospyros Nika Vitax negundo Buruta swietenia ebenem Burutha Chloroxylon Karanda Pongamia Manilkara swietenia pinnata Palu hexandra Coconut Cocos nucifera Karawu Margaritaria Pihimbiy Felicium indicus a decipiens Lepisanthes Ketakela Bridelia retusa Puwak Areca catechu Dambu tetraphylla Lepisanthes Schleichera Rata Citrus grandis Dambu tetraphylla Kolon oleosa jambola Dan Syzygium Kon Schleichera Rath caryophyllatum oleosa nithul Del Artocarpus nobilis Kotadimb Ficus hispida Sapadilla Achras zapota ula Domba Calophyllum Kottamba Terminalia Siyambal Tamarindus inophyllum catappa a indica Ehela Cassia fistula Kumumell Diospyros Thel a ovalifolia kaduru Sapium insigne Etamba Mangifera Lunumidel Melia dubia Thimbiri Diospyros zeylanica la malabarica Ethdemata Gmelina arborea Madan Syzygium Weera Drypetes cumini sepiaria Gal Weera Drypetes gardneri Maila Bauhinia Drypetes racemosa Wira sepiaria Gammalu Pterocarpus Makul Hydnocarpus marsupium venenata Godapara Dillenia racemosa Mango Mangifera indica

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Table 67 : List of proposed plant species for understory afforestation

Common name Scientific name Bulu nelu Stenospiphonium cordifolium Dedi kaha Memecylon capitellatum Dodampanna Glycosmis mauritiana Heen eraminiya Ziziphus oenoplia Heen karamba Carissa spinarum Karapincha Murraya koenigii Kilimessa Miliusa indica Kuratiya Phyllanthus polyphyllus Maha rathabala Ixora pavetta Migon karapincha Clausena indica Neralu Cassinea glauca Pupula Vernonia zeylanica Ulkenda Polyalthia korinti Vala venna Adiantum caudatum Wal kahabiliya Tragia hispida Weliwenna Dimophocalyx glabellus

30. The riverine forest can be reinstated along the banks of two streams which join the Per Are at its upstream as shown in Figure 33. On the both banks of the river, bank stabilizing species will be planted as listed in Table 68. On the ground the herbaceous aquatic plant Cryptocoryne becketti (Ati Udayan) can be planted at the very edge of the river. In addition to this the semi aquatic herb Crinum defixum (Heen Tholabo) can be planted at the edge of the river. This project will have some positive impacts to protect reverine forest in downstream of the reservoir by providing environment flow during the dry season. However, the water released as environmental flow will not depict the natural condition during the wet month although during the very dry month it would be an advantage as the river in its current form does not have any water.

Table 68 : Proposed plant species for afforestation at riverine areas

Common name Scientific name location Yellow Bamboo Bambusa vulgaris Inner edge of river banks Green Bamboo Dendrocalamus strictus Inner edge of river banks Wetake Pandanus thwaitsei Inner edge of river banks Rambuk Saccharum arundinaceum Inner edge of river banks Wewel Calamus spp Inner edge of river banks Ati Udayan Cryptocoryne becketti Edge of river banks Heen Tholabo Crinum defixum Edge of river banks Kumbuk Terminalia arjuna Stream reservation area

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Mee Stream reservation area Kekuna Stream reservation area Puwangu Stream reservation area Bakmee Stream reservation area Source: Hydrological Studies for Per Aru Reservoir, 2011 31. The afforestation program has to be prepared according to the guidelines of the Forest Conservation Department. Prior to starting the plantation, types of plants, their specifications, availability and planting locations need to be ensured. Thus, it is required to receive the consultative support of the officers of the Forest Conservation Department. Details of afforestation are shown in Table 69.

Table 69 : Extent of forest inundation and afforestation

Type of forest Extend under inundation (ha) Extent for afforestation (ha) Dry monsoon forest 146 148 Open & sparse forest 18 19 Scrub jungle 4 5 Riverine forest 0 50 Total 168 222

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Figure 33 : Proposed locations for afforestation

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l. Potential wildlife corridor

32. There are no wildlife reserves in close proximity of the proposed reservoir location as shown in the present Wildlife Conservation map in Figure 3. However, in the report of the Integrated Strategic Environmental Assessment (ISEA), which was recently conducted for the Northern Province, there is a proposal to establish a jungle corridor with a view to connecting Padaviya Proposed Forest Reserve and Giant Reservoir Sanctuary which is shown in Figure 30. More details of the proposed jungle corridor are shown in Figure 33 and Figure 35. These figures clearly show that only a part of the proposed reservoir is located at the southern border of this proposed corridor leaving ample room for animal movements. Thus, the proposed reservoir does not obstruct the corridor path at all. Thereby the increased availability of water in the reservoir will attract more wildlife to the area especially during the dry season. 33. During the construction period, it is necessary to put in place adequate measures for the safety of the workers against potential attacks from wild animals, especially from wild elephants. All non residential workers can be provided with transport by the contractor from the town area to the work site in the morning and back to the town in the evening. By providing two security points with barriers at both ends, movement of general public within the construction site can be restricted. Work site will also be surrounded by a temporary fence to ensure the safety of workers from wild animals.

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Figure 34 : Proposed elephant corridor and moving path of animals

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Figure 35 : Reservoir boundary over the elephant corridor

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B. Sustainability on critically endangered fauna species 34. Chapter III shows that there were three critically endangered species observed within the inundation area. They are one butterfly (Japonia vesca -Table 33) and two land snails (Mycalesis visala, Euplecta colletti - Table 43). These tables also describes the habitat types of each species as defined by the field staff. Particular habitat types were not mapped for the identification of boundary or extents. Thus, it is not possible to make a quantitative evaluation of the lost habitat as a result of inundation. Therefore habitat of each species was referred to the land cover types shown in the forest cover map produced by the Forest Conservation Department and land use types shown in the topographical maps produced by the Survey Department. Figure 36 shows the paths of transect lines of the field survey over the map produced by incorporating so-called land cover / land use types of respective regulatory authorities. 35. Each species was observed through a transect survey. Details of transect line numbers with respect to each species together with starting point and end point GPS coordinates of each transect line number are furnished. Since approximate offset locations of the observed species were not recorded habitat of each species was referred to the neighbourhood habitats of the respective transect line number. The neighbourhood land cover types of reference transect line number are shown in Table 70 and the possible habitats of critically endangered fauna species are shown in Table 71.

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Figure 36 : Transect survey lines over classified land cover and land use areas

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Table 70 : Details of near threaten fauna species related to classified land covers

Type Scientific name Common name Conservation Transect Land Cover Status Bird Elanus caeruleus Black-Wing Kite NT Chinnakulam, Velankulam Bird Ceyx erithacus Oriental Dwarf Kingfi NT T21, T14, Dry Monsoon forest, sher T16,Velankulam Scrubs, Stream, Non forest and Paddy Bird Anthracoceros coronatus Malabar Pied Hornbi NT T14. T18, T21, Dry Monsoon forest, ll :Periyakulam, Scrubs, Stream, Non Velankulam forest and Paddy Bird Ciconia episcopus Woolly- NT T16, T20, T8, Dry Monsoon forest Necked Stork Periyakulam, and Non forest Velankulam Bird Surniculus lugubris Drongo Cuckoo VU Velankulam, Periyakulam Bird Pellorneum fuscocapillum Sri Lanka Brown- NT T2, T8, T6, Paddy, Dry Monsoon Capped Babbler T11,T4, T18, forest and Non forest Periyakulam, and Stream, Velankulam Butterfly Badamia exclamationis Brown Owl VU T21, T8, T2, T9, Dry Monsoon, T18 Scrubs, Stream, Non forest and Paddy Butterfly Anthene lycaenina Pointed Ciliate Blue VU T8, T14 Dry Monsoon forest, Non forest Stream Butterfly Neopithicops zalmora Quaker NT T8, T14 Dry Monsoon forest,

ainlWtrSpl n riaeBad EIA Studyon PerReservoir Aru National WaterSupply and DrainageBoard Non forest, stream Butterfly Charaxes psaphon Tawny Rajah NT T2, T21, T10 Paddy,Scrubs,Dry Monsoon forest Butterfly Charaxes solon Black Rajah NT Velankulam, Periyakulam Butterfly Cirrochroa thais Tamil Yeoman NT T8, T14, T21, Paddy, Scrubs, Dry T18 Monsoon forest, Non forest and Stream Butterfly Mycalesis visala Tamil Bush Brown CR T2, T16 Paddy, Dry Monsoon forest, Non forest Butterfly Colotis amata Small Salmon Arab NT T11, T16 Dry Monsoon forest, Non forest Mammal Macaca sinica Sri Lanka Toque Mo NT T2, T21, T8, Dry Monsoon forest, nkey T14, Scrubs, Stream, Non Velankulam, forest and Paddy Periyakulam Mammal Semnopithecus vetulus Purple- VU T8, T6, T14, Dry Monsoon forest, Faced Leaf Monkey Velankulam, Non forest, Stream Mammal Periyakulam Mammal Semnopithecus priam Grey Langur NT T8, T6, T10, Dry Monsoon forest, T13, Non forest, Stream Mammal Velankulam Mammal Elephas maximus Elephant VU T21, T16 Paddy, Scrubs, Dry Monsoon forest, Non forest and Stream Mammal Felis chaus Jungle Cat VU T11, T16 Dry Monsoon forest and Non forest Mammal Prionailurus viverrinus Fishing Cat VU T8, T14, Dry Monsoon forest, Velankulam Non forest, Stream 137 137

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Mammal Loris lydekkerianus Grey Slender Loris NT N1, N5 Mammal Manis crassicaudata Pangolin NT N1, N5 Mammal Lutra lutra Otter VU T8, T20 Dry Monsoon forest, Non forest, Mammal Mammal Ratufa macroura Giant Squirrel VU T2, T8, T14, Paddy, Scrubs, Dry T20, Monsoon forest, Non Velankulam forest and Stream Reptile Melanochelys trijuga Parker's Black Turtle NT T8 Dry Monsoon forest and Non forest Reptile Geochelone elegans Indian Star Tortoise VU T9, T6 Dry Monsoon forest, Non forest and Stream Reptile Lissemys punctata Flapshell Turtle VU N1 Land snail Euplecta colletti CR T8, T2, T6, T18 Dry Monsoon forest, Scrubs, Stream, Non forest and Paddy Land snail Japonia vesca CR T8, T2, T6, T18 Dry Monsoon forest, Stream, Non forest and Paddy Fish Climbing Perch NT D8, D5

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Table 71 : Critically endengered fauna species and their habitats

Habitat Scientific Common Conservation Land cover/ As defined by Type name name Status land use type field surveys Butterfly Mycalesis Tamil Bush CR Paddy, Dry Open Scrub visala Brown Monsoon lands forest, Non forest Land Euplecta c CR Dry Monsoon Open Scrub snail olletti forest, Scrubs, lands, Dense Stream Forest, Forest, (Riverine), Riverine Forest Non forest and Paddy Land Japonia v CR Dry Monsoon Forest, Riverine snail esca forest, Stream, Forest Non forest and Paddy 36. As shown in Table 71 the survey team has found critically endangered butterfly in open scrub lands which contain scattered bushes in open areas. It matches with non forest areas and paddy field areas according to the land classification map shown in Figure 36. The paddy cultivation is practiced only during the wet season and rest of the period these lands are used for crop cultivation. Table 72 shows each classified land cover type as a percentage of total inundation area and as a percentage of similar land cover type available in the study area as well as in the catchment area.

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Table 72 : Land cover types in inundation area, study area and catchment area.

Each Each Each LC in IA Each LC Each LC in Each LC in IA as Land cover (LC) LC Area LC Area as a % of Area of IA as a % a % of similar classification of SA of CA similar LC in IA (ha) of total IA LC in CA (ha) (ha) SA Dry Monsoon Forest (DMF) 146 448 7521 58 32.6 1.9 Open Sparse Forest (OSF) 18 77 2248 7 23.4 0.8 Shrub (Sh) 0 0 875 0 0 0 Scrub (Sc) 4 160 2152 2 2 0.2 Non Forest (NF) 21 135 3009 8 15.6 0.7 Paddy (Pd) 60 202 3852 24 29.7 1.6 Chena (Ch) 0 0 1079 0 0 0 Water Bodies (WB) 1.5 29 1707 1 5.2 0.1 Garden (Gd) 0 14 2440 0 0 0 Road (Rd) 0 1 51 0 0 0 Rock (Rk) 0 0 15 0 0 0 Total LC Area 250.5 1066 24949 100

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37. According to the Table 71. lost habitat of all CR type fauna species comprise of dry monsoon forest, scrub, non forest and paddy. Table 72 shows that the extent of lost dry monsoon forest in the inundation area is 58% of the total inundation area and 32.6% of the similar habitat in the study area and 1.9 % of the similar habitat in the catchment area. The extent of lost scrub forest in the inundation area is 2% of the total inundation area and 2% of the similar habitat in the study area and 0.2% of the similar habitat in the catchment area. The extent of lost “non forest” in the inundation area is 8% of the total inundation area and 15.6% of the similar habitat in the study area and only 0.7% of the similar habitat in the catchment area. Lost paddy land area is 24% of the total inundated area and 29.7% of the similar habitat in the study area and 1.6 % of the similar habitat in the catchment area. Percentage values of lost habitat show that a significant extent of similar habitat is available in the close proximity and within the catchment area. However, occurrence of these species will be monitored during the construction and operation periods in order to assess the project’s potential adverse impacts on the butterfly’s ecology. 38. Table 73 shows the total lost habitat of each CR type fauna specieswith a comparison of similat habitat in the study area and the catchment area.

Table 73 :Total lost habitat of each critical endangered species

Critically endangered fauna Extent of lost Extent of lost Extent of lost habitat as a % habitat as a habitat as a % of Type Scientific Land cover of total % of similar similar habitat in name types of inundation habitat in the the catchment habitat area study area area Butterfly Mycalesis Paddy, Non 91 29 1.5 visala forest, and Dry monsoon forest Land Euplecta Paddy, Non 92 24 1.4 snail colletti forest, Dry monsoon forest and scrub Land Japonia Paddy, Non 91 29 1.5 snail vesca forest, and Dry monsoon forest

39. Table 77 shows that 91 – 92 % of the inundated area is occupied by the CR species to establish their habitat which varies from 24% to 29% of the study area. The total lost habitat is nearly 1.5% of the total catchment area. This emphasis that 98.5% of the catchment area has a favourable eco-system for the sustainability of the critically endangered species observed in the study area. 40. Percentage values of lost habitat show that a significant extent of similar habitat is available in the close proximity. Before the construction, a survey of the affected area will be

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir carried out to confirm the existence of these species in the construction and inundation areas. If such species is found it will be trans-located into a safe habitat for the snail. Occurrence of these species will be continued to be monitored during the construction phase and the operational phase in order to undertake necessary trans-location. 41. Conservation of critically endangered species during construction and operation period is included in the monitoring plan. A bio-diversity specialist will be engaged for the monitoring during construction and operation. Close monitoring during construction will ensure that any potential impacts are limited to within the designated construction areas. Also, the bio-diversity specialist will monitor occurrence and/or re-occurrence of the endangered fauna pieces in and around the construction site in order to assess the the effectiveness of the mitigation measures. During the operation period, monitoring will be continued at six month intervals in the reforestation areas and the area near the stream to ensure the mitigation measures of negative impacts have been put in place and are effective.

1. Mitigating the impacts on aquatic fauna and flora 42. The aquatic fauna and flora can be impacted from construction of a reservoir cum dam across the river, will be . For mitigating the low availability of water in the downstream, an environment flow will be released throughout the year including the dry months when there is hardly any flow in the river, to compensate for the loss. The requirement of this is observed in the biotic survey which recorded that at least one species (Labeo dussumieri) recorded in the river will require triggering flows for breeding and the 14 species of dragon flies may also require triggering flows for moulting while over bank flows will be required to maintain the structure of the riverine forest. Further, the migratory patterns of the fish will also be affected by this barrier and it is expected to be compensated by having the separate outlet for the environment flow always. In addition to the outlet for the environment flow, two sluices will be made at 69.0 MSL for 2 ft. dia. pipe and at 67.5 MSL for 1 ft 6” dia. pipe in the left bank of spillway to encourage fish migration. 43. Due to ponding, the water quality of the reservoir may be altered. However, as the water is pumped out regularly for treatment for drinking purposes, waters will be aerated to a certain extent and it will be beneficial to the aquatic organisms. In case this is not adequate, it is required to aerate the reservoir through additional measures. 44. There were 3 endemic fish species and one nearly threatened species observed in the main river. The endemic fish (Flying barb / Bearded rasbora, Lanka labuca and Filamented Barb) are endemic but do not fall into the endangered/nearly threatened or vulnerable categories. Though the Climbing perch is not an endemic species it falls into the nearly threatened category. Due to the inundation of these lands all the terrestrial animals will greatly be affected than aerial animals. Feeding and nesting grounds of reptiles and mammals will be disturbed and dislocated. These animals will try to escape to safer localities especially in the upstream situation would enhance the encroachment of the territories of inhabitants of such areas. Such circumstances could create inter population and intra population conflicts. To maintain the aquatic spices movement between both sides of the dam, a fish pass was designed and will be implemented. The environment flow and the fish pass will ensure tha the adverse impacts on aquatic species including endangered aquatic species, is minimal.

2. Mitigating measures for new agricultural lands 45. As the present land use of the proposed resettlement sites is forest, there would be contamination of water bodies from soil erosion and sedimentation resulting from clearing of forest land . After the land is prepared for cultivation, soil conservation measures that were

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outlined earlier in this chapter should be adhered to prevent further erosion and water contamination. Natural drainage paths need to be left intact or alternative ones need to be prepared prior to operation.

3. Mitigation of air pollution impacts in construction phase 46. Mitigation measures to control air pollution impacts during construction period are essential, even if the impacts are relatively short term. Table 74 indicates methods for mitigation of same that will be made conditional in the in the civil works contract and implemented during the construction period.

Table 74 : Mitigation of air pollution during construction period

Anticipated Air Proposed Mitigation Measure Pollution Impact during Construction Particulate Emissions Introducing and maintaining good housekeeping practices. from construction Workers to be provided dust masks to prevent exposure to material, quarrying of soil fine dust. Transportation of metal, These materials should not be transported open. Cover soil and waste material construction materials or waste materials adequately during transportation Dust generation from Watering exposed areas at least twice a day (morning, clearing and reclamation afternoon) of lands Emissions from Positioning polluting machinery away from sensitive receivers construction machinery Open burning of solid Prevent open burning of solid waste in sites and work camps waste to the extent possible. Prepare appropriate collection places for solid waste within the work sites. Adopting reuse and recycling of solid waste within site. Emissions from other Proper In-house vehicle inspection and maintenance vehicles program. Enforcement of the emission norms established by the CEA (Vehicle Exhaust Emission standards gazetted in 2003). This can be done when awarding contracts to contractors or when hiring the vehicles.

47. Also paving and maintaining road surfaces, using water trucks to wet the unpaved roads, establishing good house-keeping practices to maintain the construction areas clean, and conducting regular awareness programmes on consequences of air pollution and strategies of air pollution mitigation for the staff and the workers, will bring down air pollution drastically. The workers who are directly exposed to fumes, solvents, dust etc. should be provided with protective gear.

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4. Mitigation of air pollution impacts in operation phase 48. During the operation stage the air quality is expected to reach the baseline values. The presence of the reservoir will affect the microclimate beneficially. Maintenance of good roads will contribute to keeping the environment safe and clean for all. The occasional operation of the diesel generator may create some air pollution but this is not regular. Maintaining the condition of the generator by servicing it regularly will help to reduce the pollution emanating from it. Regular monitoring of ambient air quality levels, good house-keeping practices, maintenance of green (tree) belts along roads and sites, regular awareness programmes on consequences of air pollution for the staff and workers involved in operations, will help in improvement of air quality in the project area.

5. Mitigation of noise and vibration impacts during construction 49. Measures for mitigating impacts of noise and vibration should be adopted during the construction period spanning 3 years. The principal sources of noise and vibration during the construction phase of the project will be operation of the heavy machinery and vehicles. The correct operations, maintenance and site practices of those equipments are the most effective method of mitigation of impacts of noise and vibration. 50. The adjacent communities would be affected by the noise and vibration during construction phase. There are many ways to control noise emanting from construction with good site practices. These include • Equipment fitted with adequately sized exhaust silencers. • Use of silenced equipment wherever possible. • Providing engine enclosures for equipment • Use of low noise equipment (such as hydraulic jacking of piles vs. percussion driving) • Keeping equipment in good working order and follow manufacturers’ instructions carefully • Minimizing the use of noisy equipment such as drills, compressors, circular saw etc. • Scheduling activities so as to avoid high noise levels • Positioning of equipment as far as practical from noise sensitive receivers • Use of temporary noise barriers, screens or earth banks. • Installation of noise generating machinery on resilient foundations to reduce vibrations and noise • Enclosing stationary machinery (wherever possible) using suitable material to isolate the machinery. 51. It may not be possible to specify the construction methods to be employed by the contractor. The noise and vibration control requirement of equipment will be specified in the contract documents to meet a specific standard.

6. Mitigation of noise and vibration in the operation 52. The noise and vibration levels are expected to return to the baseline levels in the operation phase. • Most of the measures for mitigation of impacts of noise and vibration in the operation phase could be achieved by good design of roads and other infrastructure. • Noise abatement actions should be adapted to control the noise level at the boundary of sensitive areas at 55 dB (day) and 45 dB (night).

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53. Construction of noise barriers should be erected around the water treatment plant. Maintaining a thick green belt along the roads will help to bring down the noise levels. (But a roadside green belt should be staggered at several locations to prevent concentrations of air pollutants). Vegetation existing in the sites should be preserved. It will also serve as a visually pleasing landscape.

7. Grievance redress mechanism 54. A grievance mechanism was established with the representation of the affected persons to allow them to appeal against any unssatisfactiry decisions regardless of efforts to provide fair levels and methods of compensation and mitigation that are appropriate for the loss. 55. The Grievance Redress Committee (GRC) is chaired by the Divisional Secretary of Vavuniya with representatives from the relevant local government agencies, Regional Office (RO), Community based organizations (CBOs), and Farmer Organization (FO). The GRC meets every month and determines the merit of each grievance, and try to resolve grievances within a month of receiving the complaint. The GRC provides attested copies of their decision to the Affected People and the RO for records. Where Affected People are not satisfied with the GRC’s decision, the Affected People can resubmit their case. Further grievances may be referred by Affected People to the appropriate courts of law. The RO keeps records of all grievances received including: contact details of complainant, date that the complaint was received, nature of grievance, agreed corrective actions and the date these were effected, and final outcome. The grievance redress process is shown in Figure 37.

Figure 37 : Grievance redress process

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a. Mitigatory measures on socio-economic and cultural issues

56. Private/Common properties identified within the reservoir’s full supply level boundary with environmental buffer zone (71-m MSL contour and 100-m buffer zone) and within the proposed Water Treatment Plant site are not significant. Only 3 temporary houses, six masonry wells, five earth wells and a Hindu temple identified were within the said boundary. However, it is clear that the private households could be rebuilt the within the remaining land areas or on the new land depending on owner’s choice. The owners of the wells will be compensated at replacement cost or the same facility will be established on their new land. Physical relocation has not been agreed among other Affected People except three households. 57. The Amman temple located below the Pandara Periyakulam bund is an ancient folk temple maintained by the Pandari community. According to them the temple has more than a 200 year history. Since it is a folk temple, it opens once a year for festival. The existing structure of the temple is very simple. The walls are made of bricks and cement, and tin sheet is used for roofing. The total area of the temple comes approximately 500 square feet. No concrete structures or sculptures are in the existing structure of the temple. 58. In case of the Hindu temple a discussion was initiated with the Affected People regarding the reconstruction of the temple. The discussion revealed that temple should be relocated at the same premises by raising the ground level above the reservoir water level and finally agreed. 59. Impacted from the project are the occupants of 3 temporary houses located in the buffer zone who will have to be relocated..They were resettled through the government resettlement program after the 30-year conflict. Initially the returnees were resettled in temporary houses and later on these families were absorbed into permanent housing programs. These three families were not included in the permanent housing programs because they were to lose land due to the project and they do not own additional lands. Resettlement plan prepared for the project has made appropriate compensation provisions for affected occupants of these dwellings who are not the legal owners of this land As a result, the resettlement budget allocates funds for the construction of houses (03 houses) on the lands identified by the Government Agent’s Office. 60. Land acquisition for the sub project in Vavuniya caused economic displacement and thus largely affecting their livelihood. Economic displacement due to the project is being mitigated by providing alternative land with equal status or better.

b. Alternative land option

61. The subproject will impact on cultivated lands causing economic displacement of 107 families. The inundation area of the proposed reservoir and the 100-m buffer zone around it cover 334 ha of land of which 79 ha are paddy land. On 23 ha of the remaining land, farmers cultivate seasonal crops under chena (slash-and-burn) cultivation method. There are 130 claimants to these agricultural lands of 102 ha either sole or joint land users. They are members of the affected 107 families. 62. The District Administration has identified alternative agricultural lands cultivated under 03 partially abandoned minor irrigation reservoirs namely Katkulam, Muthaliyarkulam and Pathiyakulam located close to the affected area. Katkulam is about 3.5 Km from existing Pandara Periyakulam tank.The site is easily accessible across the proposed gravel surfaced bund. The proposed alternative land is situated downstream of the proposed reservoir. The site is flat, with favorable conditions for cultivation. The feasibility report prepared by the Department of Agrarian Services revealed that a total of 174-acres are available respectively under three

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irrigation reservoirs for catering to alternative land requirement. Apart from this, Department of Agrarian Services has a list of owners for 170-acres of land in the command areas of these resrrvoirs although they have not produced documents. Therefore further investigations for identifying suitable agricultural lands is still in progress. The Figure 4 shows that there are number of minor irrigation reservoirs located at the downstream of the proposed reservoir. Besides that, it is required to obtain the clearence from Forest Conservation Department, if any identified land falls within the forest conservation areas.

c. Mitigating the impacts of transportation of the area

63. The existing road across Per Aru will be diverted parallel to the bund. Further, a small road will also be made on the bund for walking and for lighter transport. These interventions will minimize the impact imposed on transportation by the Project.

d. Maintenance, operation and regular inspection

64. Practices to ensure safe operation of the dam and the reservoir need to be defined. Written operating instructions (Standing Operation Procedures) should be prepared for the dam and its associated structures and equipment. In order to ensure dam safety the instructions should cover the functions of the dam and the reservoir and the procedures to follw during flood conditions need to be be with the local operating unit established close to the dam. 65. Security should be provided to prevent structural damage by vandals or saboteurs and unauthorized operation of outlet and spillway gates. Armed security will be necessary to counter acts of a terrorist attack. 66. Public safety at the reservoir, in areas adjacent to the reservoir and downstream of the dam should be considered. Safety measures should include posting of safety instructions and public announcement through news papers, radio and television of an impending danger. An Emergency Action Plan and an Inundation Hazard Map of downstream area should be prepared and available with the Local Administrative Centers as well as at the Operation Room, Engineer-in-Charge and with the Head Office of the NWSDB. Communication among the affected government bodies such as Grama Niladhari, Police, Hospitals, etc. should be maintained. 67. Maintenance checklists indicating the maintenance procedures and protective measures for each structure and each piece of operating, communication and power equipment should be prepared . Any known problems should be specifically indicated.

e. Operation staff

68. The operation staff must be qualified to perform the many functions required in the operations including recognition of conditions possibly detrimental to dam safety. Vigilance and dedication of trained O&M staff can not be replaced by any instrumentation program. A continued training and development of skills should be a part of the maintenance program itself.

f. Additional survey to address the status of endangered species

69. Additional survey and study will be conducted to ensure that the project is not adversely affected the endangered species listed in Chapter III. The habitat protection measures proposed in this report, such as afforestation and endangered species monitoring, will be up graded

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National Water Supply and Drainage Board EIA Study on Per Aru Reservoir based on the study. Additional measures will be adopted as required for the sustainability of endangered species. For each critically endangered species and endangered species, specific protection measures will be prepared based on the survey. The NWSDB has committed to implementing these protection measures for the endangered species. A report on biodiversity and critical habitat protection and management will be also prepared after the survey before the commencement of civil works. 70. The report will be prepared in order to (i) study the extent of the habitat for these species in a wider spreading area around the proposed reservoir; (ii) assess the project’s impact on the subject species and the need for any additional mitigation and management measures; (iii) prepare specific protection, mitigation and management plans for each species; and (iv) prepare an overall habitat management plan for the project area.

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VI. ENVIRONMENTAL MANAGEMENT PLAN AND COST BENEFIT ANALYSIS

A. Environmental management activities 1. The anticipated environmental impacts and the proposed mitigation measures of the Per Aru drinking water reservoir project have been discussed in Chapter IV and V of this report respectively.Due to the inundation of the proposed reservoir a considerable forest will be lost. The proposed mitigation measure is to plant trees over the land areas identified as suitable for tree planting. The afforestation extent shall be equivalent to the area of forest lost. The identified locations and technical details of planting including plant species, spacing and practices are presented in Chapter IV. Impacts during the construction phase and operational phase need to be controlled and closely monitored while assuring the sustainability of the environment. Environmental management plan is shown in Table 75.

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Table 75 : Environmental management plan (EMP)

Environmental Mitigation Measures (MM) Timing to Locations to Resp mon Objectives Resp. imp MM concern recommended implement MM implement MM MM

A. Pre-construction stage

1.Social To ensure that the 1. Social preparation of the APs to be Before the Affected cultivation PMU with the support NWSDB Impacts, adverse impacts completed prior to commencement of removal of lands inside the of other line agencies and resettlement and due to the property construction. houses and proposed reservoir consultants reallocation of acquisition and acquisition of bed and 03 families lands resettlement are 2. Acquisition of lands completed to cultivation living in temporary mitigated minimize the uncertainty of people. lands, the APs houses located according to be given within the 100 m government 3. Completed implementation of land sufficient time buffer zone. regulations. acquisition and relocation plan (LARP) with to provide compensation and compensation assistance to the APs. money and assistance to 4. All the impacts identified by the EIA resettle were incorporated in to the LARP. satisfactorily. 2. Avoid 1. Choose non-polluting or enhancing Before Construction sites, PMU, contractor and NWSDB Environmentally environmental methods. Contractor to submit Method commencement stores, material consultants and responsible pollution. Statement and schedule of of the work yards, camps, consultants procurement environmental mitigation measures in offices, workshops response to EMP with tender. Include etc as in the project enhancements, techniques to reduce layout impacts.

3. Environmental Avoid 1. Contractual conditions included to Before Lands identifies as PMU with the support NWSDB sustainability environmental tie the implementation of commencement per EIA report of other line agencies and losses/ environmental mitigation measures. of the work consultants degradation due to project 2. Preparation of afforestation plan for implementation. plant varieties and number of plants from each varieties as per EIA report

3. Demarcation of afforestation lands as per EIA report

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 4. Hydrological To minimize 1. Ensure surface flows are controlled From the design River guage location PMU and consultants NWSDB Impacts hydrological and and facilitated by releasingh stage and drainage impacts environmental flow to the downstream consultants during of the river as stipulated in EIA report . constructions. 2. Ensure the e-flow rate by monitoring river guage readings 5. Water To minimize 1. Availability of water will be assessed Prior to Relevant locations Contractor NWSDB Resources impacts on local to evaluate the impact on community construction. are all local water and water supply resources. supply resources Consultants caused by and rivers. construction activities are minimized.

6. Drainage and To minimize 1. Drainage management plan, Before start the All streams and river PMU with the support NWSDB erosion control impact on work crossings, exixting of consultants and drainage drainage paths and consultants dried drainage paths.

7. Soil To minimize 1. Soil conservation paln Before start the As per soil PMU with the support NWSDB conservation impact on soil work conservation plan of consultants and erosion consultants

8. Planning To plan to 1. Planning sites for worker camps and Before start the Locations decided by Contractor. NWSDB construction minimize the effect back up areas for stockpiling materials work PMU with the and camps of the work camps and equipment in advance. Contractor. consultants on the surrounding environment and 2. Planing for adequate sanitary residents in the facilities and monitoring area. 9. Waste Tominimize the 1. Waste management plan; Before start the Locations decided by Contractor. NWSDB management effect of the work work PMU with the and camps on the Contractor. consultants surrounding environment and residents in the area 151

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 152 10.Noise & dust To plan to 1. Noise and dust control plan, Before start the Locations decided by Contractor. NWSDB control minimize the effect work PMU with the and of the work camps Contractor. consultants on the surrounding environment and residents in the area

11. Institutional Prepare PMU for 1. Develop strengthening plan for the Before start the Locations decided by Contractor/PMU/Cons NWSDB strengthening implementation of environmental management work PMU with the ultants and and capacity EMP. Contractor. consultants building 2. Prepare awareness and training programs 3. Prepare evaluation program for the environmental requirements and contractors’ mitigation measures.

12. Prepare Full and effective 1. Prepare contractors to co-operate During pre- Throughout the Contractor/PMU/Cons NWSDB contractors for implementation of with the executing agency, project construction no project ultants and implementation environmental management, supervising consultants later than one consultants of EMP mitigation and local population in the mitigation month after measures. of impacts. Include the approved EIA contract award. and the EMP in the contract documentation. 2. Contracts must require full implementation of the EMP 3. Contractor to engage capable and trained environmental management staff to audit the effectiveness and review mitigation measures as project proceeds. 4. The effective implementation of the EMP audited as part of the loan. 5. PMU to prepare resources to fulfill the requirements of the EMP.

B. Construction stage

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 1.Orientation for To ensure that the 1. Conducting special briefing and Before Through out the Contractor and NWSDB Contractor, and contractors and training for contractor on the commencement project recorded details and Workers workers environmental requirement of the of the work Consultants understand and project. Record attendance and have the capacity achievement. to ensure that the environmental 2. Conducting special briefing and / or Induction for all requirements for on-site training for the contractors and site agents and mitigation workers on the environmental above before measures are requirement of the project. Record commencement implemented. attendance and achievement. of work.

3. Agreement on critical areas to be At early stages considered and necessary mitigation of construction measures, among all parties who are for all involved in project activities. construction employees as far as reasonably practicable. 4. Periodic progress review sessions During the to be conducted every six months construction 2. Plans to Avoid impacts 1. Drainage management and soil Two weeks Through out the contractor and with NWSDB control drainage from unplanned conservation plan, before project and area the support of PMU and associated activities construction concern for Consultants impacts and soil 2. Providing adequate drainage commences for environmental erosion facilities any given sustainability stretch. 3. Providing soil conservation bunds and sedimentation ponds 3. Traffic Avoid impacts 1. Avoiding blocking existing roads During the As per physical work Contractor NWSDB Condition from unplanned and other access near the works route construction program and activities during construction. consultants 4. Water quality To prevent 1. Carrying out standard water quality During the Streams, wells, Contractor NWSDB adverse water tests in regular intervals and construction irrigatio reservoirs, and quality impacts evaluation. Training of operators and and other Consultants due to negligence other workers to avoid pollution of waterbodies within and ensure water bodies by the considerate the project premises unavoidable operation of construction machinery impacts are and equipment and reporting and managed feedback by PMU 153

effectively. 2. Storage of lubricants, fuels and EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 154 other hydrocarbons in self-contained dedicated enclosures (> 30 m away from water bodies) 3. No stockpiles next ling to water bodies. 4. Proper disposal of solid waste from construction activities & worker camps.

5. Borrow sites should not be close to sources of drinking water. 5. Water To minimize 1. Camps will be located at least 100m At the Relevant locations Contractor NWSDB Resources impacts on local away from the nearest local settlement commencement as per site conditions and water supply . of the Consultants caused by construction. construction activities are 2. Project water will be obtained During the Relevant locations Contractor NWSDB minimized. without depleting local village supplies. construction as per site conditions and Consultants 3. The contractors will be required to maintain close liaison with local communities to ensure that any potential conflicts related to common resource utilization for project purposes are resolved quickly.

4. Guidelines will be established to minimize the wastage of water during construction operations and at campsites. 6. Spoil disposal To minimize the 1. Implement Waste Management During the Locations approved Contractor. NWSDB and construction environmental Plan. construction by PMU and waste disposal impacts arising Consultants from generation of 2. Confirm conditions and safety of spoil waste, reuse proposed disposal sites. where possible and provide 3. Confirm amounts of surplus rock adequate disposal based materials that can be reused in options for the project or by other interested unsuitable soils. parties for public projects.

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 4. Confirm sufficient locations for disposal of surplus materials as in the estimate. 5. In contracts specify locations for disposal of all construction waste and spoil. 6. used oil and lubricants shall be reused or removed from the site in full compliance with the national and local regulations. 7 Waste oil must not be burned. – Oil and solid waste disposal location to be agreed with PMU and local authority.

8 Open burning is contrary to good environmental practice and will not be allowed. 7. Noise To minimize noise 1. Install, maintain and monitor all Maximum As per EIA report Contractor and PMU. NWSDB level increases requisite mitigation as per contract and allowable noise and and ground machinery shall be fitted with acoustic levels as Consultants vibrations during insulation as much as possible indicated in the construction EIA report. operations. 2. Hammer-type pile driving operations shall be avoided during nighttime.

3. Well-maintained haulage trucks will be used with speed controls. 8. Air quality To minimize 1. Control all dusty materials at Dust control 1. A list of locations Contractor. NWSDB effectively and source. planning will be to be prepared by and avoid complaints a line item in the Contractor 02 Consultants due to the airborne 2. Stockpiled soil and sand shall be accordance with weeks prior to particulate matter slightly wetted before loading, the dust commencement of released to the particularly in windy conditions. producing construction. All atmosphere. 3. Fuel-efficient and well-maintained activities of the concrete plants, haulage trucks shall be employed to worl plan. The burrow pits, any minimize exhaust emissions. schedule of rock crushing plants 155

4. Vehicles transporting soil, sand and spraying water and temporaty EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 156 other construction materials shall be to be revised access roads covered. Limitations to speeds of such monthly vehicles necessary. Transport through densely populated area should be avoided. 5. Spray bare ground areas, temporary access rosads with water.

9. Soil Avoid soil 1. Contractors to instruct and train Instruct before Every possible Contractor NWSDB Contamination contamination workforce in the storage and handling works location where such and of materials and chemicals that can commence and activities are taking Consultants potentially cause soil contamination. throughout all place construction 2. Accidentally spills on open ground works. including the top 2cm of any contaminated soil shall be disposed of as chemical waste to a disposal site acceptable to the local authority / community. 10. Work Camp To ensure that the 1. Confirm location of work camps in Update once a Location Map is Contractor NWSDB Location and operation of work consultation with PMU and local month prepared by the and Operation camps does not authorities. Location subject to Contractor as Consultants adversely affect approval by the PMU. If possible, stipulated in the the surrounding camps shall not be located near condition of contract. environment and settlements or near drinking water residents in the supply intakes. area. 2. Water and sanitary facilities shall be provided for workers and employees.

3. Solid waste and sewage shall be managed according to the national and local regulations. As a rule, solid waste must not be dumped, buried or burned at or near the project site, but shall be disposed of to the nearest site approved by the local authority.

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 4. Portable lavatories or at least pit latrines will be installed and open defecation shall be discouraged and prevented by keeping lavatory facilities clean at all times. 5. The Contractor shall document that all liquid and solid hazardous and non- hazardous waste are separated, collected and disposed of according to the given requirements and regulations. 6. At the conclusion of the project, all debris and waste shall be removed. All temporary structures, including shelters and toilets shall be removed.

7. Exposed areas shall be planted with suitable vegetation. 8. The PMU shall inspect and report that the camp has been vacated and restored to pre-project conditions as far as is reasonably practicable. 11. Safety To ensure physical 1. Submit Safety Plan one month During All areas where the Contractor NWSDB Precautions for safety of workers before commencement of construction project activities are and Workers construction. taken place. Consultants 2. Providing adequate warning signs. 3. Providing every worker with skull guard or hard hat and safety shoes. 4. Establish all relevant safety measures as required by law and good engineering practices. 5. The Contractor shall instruct his workers in health and safety matters, and require the workers to use the provided safety equipment. 157

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 158 12. Social 1. To engage local 1. Use local labour as far as possible Claims of APs Weekly updated list Contractor NWSDB Impacts workforce and for manual work. to be solved as of current and community in the soon as construction areas Consultants Project. possible. according to the Necessary physical 2. To encourage 1. Use local educated people for evacuations to implementation plan local support for clerical and office work where be done as furnished by the the project. possible. when necessary contractor. 3.To ensure 1. Encourage monitoring of the project minimum impacts by local village groups. to people living close to the ROW. 2. Claims/complaints of the people on construction nuisance/damages close to ROW to be considered and responded to promptly by the Contractor and monitored by PMU. 3. Quarterly meetings with local heads for liaison purposes to monitor complaints. 4. Set up or maintain local communication lines via landline or satellite phone. 13. To make 1. Demarcation of afforestation lands Before close out All areas of the Contractor /PMU with NWSDB Environmental environmental as per EIA report of construction alignment. the support and and sustainability enhancements in all areas guidance of all related consultants and sustainability. line agencies 2. Implementing afforestation plan 3. Implementing recommendations of the additional ecological survey C. Operational phase 1. Water quality To ensure safe 1. Carrying out standard water quality Daily Treatment plant and Operational staff NWSDB drinking water. tests in regular intervals and other locations and evaluation. Consultants 2. Crops and Monitor 1. Monitor the growth of plants grown Operational All subprojects in Operational staff NWSDB vegetation sustainability of phase future tranches and environment 2. Carry out a rapid ecological survey consultants

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2. Cost estimates for proposed mitigating measures and appropriate monitoring activities are shown in Table 76. Sub estimates for afforestation and boundary demarcation are shown in Table 77 Table 76 : Cost estimate for mitigation measures proposed in the project

No. Description Un Qty Unit Rate (SLR) Amount (SLR) its A Construction & Operation 1 Providing soil conservation bunds Ite Allow Sum to control soil erosion m 300,000.00 2 Construction of sedimentation Ite Allow Sum ponds and silt traps to avoid m 500,000.00 sediment transportation 3 Monitoring and aware on sanitary Ite Allow Sum facilities, and assessment of water m 150,000.00 borne & vector borne deceases of work force 4 Carrying out reservoir bed No 5 100,000.00 elevation surveys for testing of s 500,000.00 sedimentation 5 Carrying out water quality tests of No 4 200,000.00 reservoir and e-flow after s 800,000.00 impounding 6 Carrying out air pollution tests at No 14 50,000.00 working sites s 700,000.00 7 Carrying out noise & vibration level No 14 25,000.00 tests in the vicinity s 350,000.00 8 Carrying out water quality tests of No 12 50,000.00 nearby water bodies s 600,000.00 B Environmental Sustainability 9 Taking flow measurement to Ite Allow Sum assess the daily average e-flow m 250,000.00 rate 10 Afforestataion over the selected ha 168 300,000.00 area at upstream and riverine (as 50,400,000.00 per Table) 11 Surveying and fixing of boundary Ite Allow Sum posts around afforestation area (as m 1,100,000.00 per Table ) 12 Erecting a fence around treatment Ite Allow Sum plant to protect from elephants m 500,000.00 13 Biodiversity assessment during Ite Allow Sum the construction phase m 1,000,000.00

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14 Biodiversity assessment during Ite Allow Sum the operational phase m 150,000.00 15 Assessment on animals getting Ite Allow Sum attracted to the reservoir m 100,000.00 16 Training programs on environment No 6 100,000.00 protection and construction safety s 600,000.00

17 Assessment on safe drinking water Ite Allow Sum by consulting the recipients of pipe m 50,000.00 borne water Toal 58,050,000.00

Table 77 : Sub estimates for afforestation and boundary demarcation are shown in

No Item Units Quantity Rate Rs Amount (SLR) Total (SLR) A Afforestation 1 Supplying recommended Nos 550 68,750.00 plant varieties for primary 125.00 growth to plant in 5 m X 5 m intervals 2 Supplying recommended Nos 500 50,000.00 plant varieties for 100.00 secondary growth to plant in between primary growth plants 3 Clearing, excavation of Nos 1050 52,500.00 pits, planting, fertilizer 50.00 applications etc. 4 Maintenance cost for three Man 120 96,000.00 years days 800.00 5 Miscellaneous 32,750.00 Sub total 300,000.00 B Fixing of boundary 6 Supplying and fixing of Nos 500 600,000.00 4"x4"x 72" reinforced 1,200.00 concrete posts in 500 m intervals 7 Surveying and Item Allow sum 500,000.00 demarcating boundaries Sub total 1,100,000.00 Toal 1,400,000.00

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1. Extended cost- benefit analysis 3. Standard measures of project worth were used in analyzing the project’s internal rates of return (IRR). Table 78 shows the cost breakdown of the reservoir project including environmental costs.

Table 78 : Cost breakdown of Per Aru impounding reservoir

Item Description Local Cost (Rs.) 1 General items 60,420,000 2 Provisional Sums 65,400,000 3 Dam, Access Road, By-road and Causeway 327,444,253 4 Spill, Radial gates spill, approach& tail canal 120,670,911 Total Project Costs 573,935,164 Contingency (10% excluding prov.sums ) 50,853,516 Sub-total estimate for reservoir 624,788,680 construction 5 Environmental mitigations and Monitoring 58,050,000 Contingency (10% ) 5,805,000 Sub-total estimate for environmental costs 63,855,000

4. In financial analysis revenue from water sales to beneficiary households were considered as project benefits. While fixing an average tarrif rate, it is assumed that 80% of the consumers use pipe borne water for domestic purposes and rest of the consumers use for commercial purposes. Economic benefits occur to households as improved access to water and reduced risk of diseases. The standard procedure to estimate these benefits to households are by willingness to pay methods. We use in this analysis incremental net benefits to households estimated by North and Griffin (1993) in the Philippines; Benefits were adjusted to Sri Lankan income levels in 2011. Total economic benefits are considered as the sum of household benefits and water revenue. Extended cost benefit analysis includes the cost of environmental mitigation costs as incremental costs over the other economic costs, if the project is to be undertaken. Economic costs and other costs are considered same.Details are shown in Table 79 and Table 80.

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 162 Table 79 :Computation of expected annual revenue of the project

No Description Uit 1-3 4 5 6 7 8 9 10 11 12 13- 20 No of Household 1 Connections Number 0 5000 10000 18000 20000 25000 25000 25000 25000 25000 25000 Expected Water 2 Consumption m3/hh/day 0 0.65 0.65 0.65 0.625 0.625 0.625 0.6 0.6 0.6 0.6 3 Annual Water Demand m3 x 106 0 1.2 2.4 4.3 4.6 5.7 5.7 5.5 5.5 5.5 5.5 4 Annual Plant output m3 x 106/year 0 4.38 4.38 4.38 4.38 4.38 4.38 4.38 4.38 4.38 4.38 5 Conveyance Loss (Assumed 20%) 0 0.876 0.876 0.876 0.876 0.876 0.876 0.876 0.876 0.876 0.876 6 Annual Revenue Water m3 x 106 0 3.504 3.504 3.504 3.504 3.504 3.504 3.504 3.504 3.504 3.504 7 Water Tariff SLR/m3 0 25 25 25 25 35 35 35 35 35 40 8 Expected collection rate 0 0.97 0.97 0.97 0.97 0.97 0.97 0.97 0.97 0.97 0.97 Expected Annual 9 Revenue SLR Million 0 29.1 58.2 104.275 111.55 193.515 193.515 186.725 186.725 186.725 213.4

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board

Table 80 :Cost benefit analysis of the project

Year 12345678910 1 Water Revenue 0.00 0.00 0.00 29.1 58.2 104.275 111.55 193.515 193.515 186.725 2 Economic Benefits 0.00 0.00 0.00 95.01 126.68 158.36 190.03 215.36 215.36 215.36 3 Total Benefits 0.00 0.00 0.00 98.65 131.53 164.42 196.94 226.33 226.33 225.75 Capital costs 4 Reservoir 208.26 208.26 208.26 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5 Water Plant 0.00 141.24 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 6 Conveyance 0.00 0.00 148.37 148.37 148.37 148.37 0.00 0.00 0.00 0.00 7 O&M 0.00 0.00 0.00 4.98 6.88 8.93 11.12 12.60 12.60 12.60 8 Total Financial Costs 208.26 349.50 356.63 153.35 155.25 157.30 11.12 12.60 12.60 12.60 9 Env.mitigation cost 21.29 21.29 21.29 0.00 0.00 0.00 0.00 0.00 0.00 0.00 10 Extended Cost 229.55 370.79 377.92 153.35 155.25 157.30 11.12 12.60 12.60 12.60 Net Benefits 11 Financial -208.26 -349.50 -356.63 -124.25 -97.05 -53.03 100.43 180.91 180.91 174.12 12 Economic -210.44 -351.68 -358.81 -54.70 -23.72 7.12 185.82 213.73 213.73 213.15 13 Extended -229.55 -370.79 -377.92 -54.70 -23.72 7.12 185.82 213.73 213.73 213.15 163

ainlWtrSpl n riaeBad EIA Study on Per Aru Reservoir National Water Supply and Drainage Board 164

Table 80 Contd.

Year 11 12 13 14 15 16 1718 19 20 1 Water Revenue 186.73 186.73 213.4 213.40 213.40 213.40 213.40 213.40 213.40 213.40 2 Economic Benefits 215.36 215.36 215.36 215.36 215.36 206.00 206.00 206.00 206.00 206.00 3 Total Benefits 225.75 225.75 226.58 226.58 226.58 217.21 217.21 217.21 217.21 217.21 Capital costs 4 Reservoir 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5 Water Plant 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 6 Conveyance 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 7 O&M 12.60 12.60 12.60 12.60 12.60 12.60 12.60 12.60 12.60 12.60 8 Total Financial Costs 12.60 12.60 12.60 12.60 12.60 12.60 12.60 12.60 12.60 12.60 9 Env.mitigation cost 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 10 Extended Cost 12.60 12.60 12.60 12.60 12.60 12.60 12.60 12.60 12.60 12.60 Net Benefits 11 Financial 174.12 174.12 200.80 200.80 200.80 200.80 200.80 200.80 200.80 200.80 12 Economic 213.15 213.15 213.98 213.98 213.98 204.61 204.61 204.61 204.61 204.61 13 Extended 213.15 213.15 213.98 213.98 213.98 204.61 204.61 204.61 204.61 204.61

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5. Table 81 shows the IRR values under each three analysis and the project is worthy to be undertaken on economic feasibility criteria as it brings benefits to large number of households. Further this feasibility remains within acceptable limits even if the environmental mitigation costs are included. The project will be acceptable at annual borrowing rates below 10.25% if the perceived project benefits reflect gains by households.

Table 81 : IRR values under benefit cost analysis of the project

Type of analysis Internal rate of return (IRR) 1 Financial analysis 7.58% 2 Economic analysis 10.90% 3 Extended economic analysis 10.25%

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VII. ENVIRONMENTAL MONITORING PROGRAM

1. Before the construction activities and award of contracts, Endangered Species Status Survey will be conducted to (i) study on the total extent of the habitat for these species; (ii) assess the project’s impact on the subject species and the need for any additional mitigation and management measures; (iii) prepare specific protection, mitigation and management plans for each species; and (iii) prepare an overall habitat management plan and reforestation plan for the project area. According to the survey, the following monitoring and environmental mitigation measures will be finalized. 2. A systematic monitoring of proposed mitigatory measures is a must for the successful implementation of the overall project. In a water resources development project like the Per Aru, this becomes a vital need for the safety and viability of the project. The Monitoring Plan presented below outlines a systematic, continuous and technical way of monitoring the environmental impacts. It also includes a description of the mitigation measures, monitoring parameters, frequency, total time period involved, responsible institutions and key persons, framework of the institutional arrangement to incorporate the findings of the MP to project implementation. In sum, it aims at monitoring environmental impacts from project construction through to project operation and maintenance. The main elements of the monitoring programme, and institutional arrangement are given in this chapter. Finally, engineering and physical guidance, which could be incorporated to contractor agreements to ensure better management of project, is also given. A. Parameters to be monitored 3. A number of parameters for monitoring have been identified by the study team in several fields mostly in areas relating to engineering, geological, ecological, and socio-economic factors. The key parameters include the following:

1. Engineering and physical aspects;

a. Construction and the operation of the reservoir project

• Land clearing and deforestation prior to construction • Soil erosion over the surface and dam slopes • Temporary buildings, labour camps, access roads • Drainage facilities and sedimentation • Material storage and burrow pit reinstatement • Settlement status of the dam • Disposal of construction waste • Construction safety

b. Air and noise pollution

• Dust control • Composition of ambient air (CO, O3, NO2, SPM)

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• Noise (noise level measurements) • Vibration (Vibration level measurements)

2. Water quality • Water quality of new reservoir and sedimentation • Water quality of downstream river and nearby water bodies

3. Ecological parameters • Afforestation at upper catchment and riverine areas • The area of the other designated areas i.e. upper catchment and river banks planted • Bio diversity assessment in the vicinity • Sustainability of endangered fauna species • Assurance of e-flow and fish culture • Animal getting attracted to the reservoir from the proposed jungle corridor

4. Public Health • General waste disposal and cleanliness • Occurrence of water borne and vector borne diseases and public health • Water quality of pipe borne water

5. Institutional arrangements 4. The overall monitoring programme needs to be divided into three phases, namely the pPre-construction, construction and operational phases. In this regard certain types of monitoring activities may have to begin early in the project cycle. The base line data presented in this study would prove valuable in most of the monitoring activities. 5. The CEA is responsible for the management and enhancement of the environment and delegates its authority, particularly in the remote and less urbanized districts, to the Divisional Secretariat. In Vavuniya, there are no environmental officers of the CEA in Divisional Secretariats and therefore, the Regional Office in Trincomalee may take the leading role in coordinating all environmental monitoring activities related to the project with the participation of the divisional administration and local community. 6. The mitigation measures recommended in this report has been built into the tender documents to the Contractor and it is expected that the Contractor comes up with his/her own environmental management plan based on the mitigations and the environmental management plan specially prepared for the reservoir and water treatment plant by the Environmental Consultant of NWSDB. The environmental monitoring will be done by the NWSDB with Design, Construction, Supervision and Management Support (DCSMS) Consultants with the aid of Environmental Specialist during the construction phase and operational phase. However it is

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proposed that the NWSDB should establish its own Environmental Management Unit to continue monitoring after the project completion. The NWSDB has to organize training to the staff of this Unit. In addition to this, it is suggested that an independent monitoring will be done by a professional identified by the NWSDB during the project period. The monitoring reports will be sent to the CEA quarterly for monitoring the compliance. 7. The likely impacts during the pre-construction, construction, and operational phases have been identified. A system of monitoring these impacts in terms of the safeguard and mitigation measures recommended is detailed in the Environmental Monitoring Plan (EMP). This will provide the framework to monitor the construction activities. This should be the responsibility of the Contractor and he/she should submit reports to the NWSDB. As this is a multi-disciplinary project all the stakeholders should be in the divisional monitoring team which will monitor the activities at least once in 3 months. This comprise of Divisional Secretariat, NWSDB and DCSMS Consultants including the Environmental Specialist, Government Agent, Forest Department, Department of Wildlife Conservation, Irrigation Department and Department of Agrarian Services, land holders, representatives of affected communities , temples, and religious organizations, NGOs and any other relevant stakeholders. NWSDB and DCSMS consultants are responsible to prepare the afforestation plan with close consultation of Forest Conservation Department (FCD) and the Wildlife Conservation Departemnt (WCD). They are also responsible to prepare biodiversity monitoring plan which is apart of the environmental monitoring plan. 8. NWSDB and DCSMS Consultants should also ensure that all those who are involved in the project including those who deal with the construction, environmental monitoring and auditing are trained and are conversant with the environmental issues relating to the project. 9. Periodic meetings should be held with all the stakeholders, especially with local communities during the construction phase, to monitor any issues, deviations or lack of compliance with the guidelines by the contractors. Also clear communication links should be established so that ground level problem is reported and remedied immediately. Table 82 shows the Environmental Monitoring Plan for the Project.

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Table 82 : Environmental monitoring plan

Specific activity in each Parameters to be Frequency Total time Institutional Responsible Cost (Rs.) subject area monitored of period framework agency Monitoring Engineering and physical aspects 1.Deforestation for Removal of logs and Bi weekly 6 months Contractor NWSDB / construction debris with the consultant guidance of CEA, DFC, WLFC and Timber Corporation

2.Soil conservation Progress of soil Monthly During the Contractor NWSDB / 300,000.00 conservation bunds, construction consultant Progressive turf over phase bund slope (down stream) & riprap protection (upstream) 3.Sedimentation outside the Functioning status of Monthly During the Contractor NWSDB / 500,000.00 reservoir sedimentation ponds construction consultant and silt traps phase including defect liability period 4.Temporary buildings & Sanitary facilities, Monthly During the Contractor NWSDB / labour camps ventilation and fire construction consultant protection phase 5.Temporary access roads Maintenance of Monthly During the Contractor NWSDB / compacted surface construction consultant gravel layer and side phase drains

ainlWtrSpl n riaeBad EIAStudy on AruPer Reservoir National Water Supplyand Drainage Board 6.Material stock piling Protective measures for Monthly During the Contractor NWSDB / Stock piles from water & construction consultant wind phase including defect liability period 7.Construction material Storage facilities, Monthly During the Contractor NWSDB / storage methods and fire construction consultant protection measures phase including defect liability period 8.Dust control Progress of water Daily During the Contractor NWSDB / sprinkling, covering of construction consultant stock piles, covering of phase including loaded haul trucks. defect liability period 9.General waste disposal Protection measures Weekly During the Contractor NWSDB / that disposed waste will construction consultant not be: (i) washed away phase including to the river course (ii) defect liability nuisance to the public period 10.Construction waste Protection measures Weekly During the Contractor NWSDB / disposal that disposed waste will construction consultant not be: (i) washed away phase to the river course (ii) harden over the ground (iii) left alone at the site after construction 11.Use of fuel & lubricants Collecting arrangement Monthly During the Contractor NWSDB / of all discarded and construction consultant used lubricants & phase greases. Safe disposal or reuse /sell 171

ainlWtrSpl n riaeBad EIAStudy on AruPer Reservoir National Water Supplyand Drainage Board 172 12.General cleanliness and Adequacy of in-house Monthly During the Contractor NWSDB / 150,000.00 public health and out-door sanitary construction consultant facilities. Accounting phase including vector & water borne defect liability diseases among work period force 13.Drainage facilities Capacity of drainage Monthly During the Contractor NWSDB / canals and canal construction consultant maintenance during phase including rainy season defect liability period

14.Sedimentation inside the Measuring silt depth annually 5 years after Contractor NWSDB 500,000.00 reservoir through a reservoir bed impounding survey 15.Construction safety Effectiveness of safety Weekly During the Contractor NWSDB / precautions, safety construction consultant measures, ILO phase including standards defect liability period 16.Removal of labor camps Free from temporary monthly From the end of Contractor NWSDB / & temporary buildings buildings and progress construction consultant of landscaping after phase until the removal end of defect liability period 17.Water pollution of Chemical quality of semi 2 years during NWSDB NWSDB / 800,000.00 reservoir and river water in the reservoir annually the operational consultant downstream and downstream river phase

ainlWtrSpl n riaeBad EIAStudy on AruPer Reservoir National Water Supplyand Drainage Board 18.Air pollution level Air quality (i) In every 5 years NWSDB NWSDB / 700,000.00 measurements (i.e. 3 month through a consultant PM10 with SPM, TDS, period in qualified SO2, NO2, CO2, and CO the laboratory ), Noise measurements construction and vibration test for phase (ii) comparison annually for 02 years in the operational phase 19.Noise & Vibration level Noise level (i) In every 6 years NWSDB NWSDB / 350,000.00 measurements and 3 month through a consultant vibration test results for period in qualified comparison the laboratory construction phase (ii) annually for 02 years in the operational phase Environmental aspects 1.Water quality at nearby Taking water quality Every 3 3 years NWSDB NWSDB / 600,000.00 water bodies and wells measurements in months consultant nearby water bodies during the affected by the construction construction (i.e. TDS, period turbidity, pH, COD, BOD) 2.Release of Environment Taking flow Twice a day Up to 5 years of NWSDB NWSDB / 250,000.00 Flow measurements to the operation of consultant ensure the e-flow rate the reservoir 173

ainlWtrSpl n riaeBad EIAStudy on AruPer Reservoir National Water Supplyand Drainage Board 174 3.Afforestation in selected Type of available & Bi weekly 30 months Selected NWSDB / 51,500,000.00 areas suitable plants. Healthy during the contractor consultant growth. Number of new initial rainy with the plants grown in the months and guidance of selected areas. then CEA, DFC & Demarcation of monthly for WLFC boundary with boundary the entire poles. duration of the project 4.Protection of water Progress of erecting a At During the Contractor NWSDB / 500,000.00 treatment plant fence around treatment construction construction consultant plant to protect from completion phase elephants 5.Biodiversity assessment Adverse impacts Monthly During the Contractor NWSDB / 1,000,000.00 during Construction phase associated with construction consultant construction, phase effectiveness of environmental mitigation measures, observed biodiversity changes in fauna, flora, habitat, and eco-system. 6.Biodiversity assessment Adverse impacts Bi annually 05 years in the Contractor NWSDB / 150,000.00 during operational phase associated with operational consultant construction, phase effectiveness of environmental mitigation measures, observed biodiversity changes in fauna, flora, habitat, and eco-system. 7.Assessment on animals The number and types Once a 3 years after NWSDB NWSDB / 100,000.00 getting attracted to the of animals in the vicinity year impoundment with the consultant reservoir of the reservoir during guidance the dry season and approval of

ainlWtrSpl n riaeBad EIAStudy on AruPer Reservoir National Water Supplyand Drainage Board FCD and WCD

8.Work force awareness on Effectiveness of training Bi annually During the NWSDB NWSDB / 600,000.00 environment protection and programs conducted construction with the consultant construction safety phase support of external or internal resource persons 9.Assessment on access to No of persons having Quarterly 5 years NWSDB Regional pipe borne water continuous supply of during the Manager – water/day operational NWSDB period Vavuniya 10.Assessment on safe No of persons affected Every 6 5 years NWSDB Public Health 50,000.00 drinking water by consulting with water related months in with the Officer the recipients of pipe borne diseases the support of water operational the medical phase officer for health (MOH) TOTAL 58,050,000.00

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VIII. CONCLUSIONS AND RECOMMENDATIONS

1. Studies undertaken for this EIA encompassed cartographical and literature surveys, field observations, subterranean ground investigations, air and water quality testing, biological sampling, house to house surveys, public scoping meetings and frequent brainstorming sessions among project consultants. 2. The project addresses a dire need in Vavuniya by providing drinking water of acceptable quality to a population of 76,701 in 21 GN divisions in Vavniya District. After a carefulexamination of alternatives, the proposed reservoir is selected which is located in a remote rural area in the Sastrikoolamkulam GN Division. The Per Aru River has not been tapped for any other use for about 8 km downstrem from the proposed dam till it meets the next tributory. Therefore there are no competing uses for its waters. The river is a perennial river, but having very low stream flow during the dry season. 3. Because of reservoir loading and the reduced flow to the downstream, the viability of fish species in the river may be impacted. A total of 21 fish species were recorded in the biotic survey and among them there was not a single threatened fish species. However, the adverse impact on fish will be mitigated to a certain extent by releasing an environmental flow which varies from a minimum flow of 0.038 cu.m/sec to a maximum flow of 0.1538 cu.m/sec.. Fish passes will also be installed in the dam to facilitate fish migration. 4. The inundation area of the proposed reservoir and its 100-m buffer zone cover about 334 ha of land of which 79 ha are paddy land. On 23 ha of the remaining land, farmers cultivate seasonal crops under chena (slash-and-burn) cultivation method. There are 130 claimants to these agricultural lands of 102 ha either sole or joint land users. They are members of the project-affected 107 families. A resettlement plan has been prepared to address economic displacement of the families through appropriate mitigation measures.. There are number of minor irrigation reservoirs in the downstream area of the proposed reservoir. Replacement land as compensation has been identified elsewhere. The project will remove 3 temporary houses located in the buffer zone. The resettlement plan provides appropriate compensation for affected occupants of these dwellings who are squatters. 5. A portion of of the proposed reservoir area falls on the southern border of a proposed jungle corridor, leaving ample room for animal movement. The Integrated Strategic Impact Assessment carried out in 2011 suggested to establish this new jungle corridor connecting the wildlife Sanctuary of Giant Reservoir from the North West part of the country to the proposed Padaviya Forest Reserve from the North East part of the country. The location of the reservoir has been selected to ensure that it does not obstruct the proposed new jungle corridor. Thus, the proposed reservoir does not obstruct the corridor path at all. Thereby the increased availability of water in the reservoir will attract more wildlife to the area especially during the dry season. 6. During the reservoir construction phase, it is necessary to put in place adequate measures for the safety of the workers against potential attacks from wild animals, especially from wild elephants. All non-residential workers should be provided with transport by the contractors from the town area to the work sites in the morning and back to the town in the evening. By providing two security points with barriers at both ends, movement of general public within the construction site can be restricted. Work site will also be surrounded by a temporary fence to ensure the safety of workers from wild animals. 7. Due to the construction of the reservoir, about 168 ha of forest which belongs to the categories of dry monsoon forest (146 ha), open sparse forest (18 ha), and scrub lands (4 ha) will be inundated. A tree survey estimated about 1559 of mature trees in the inundated

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areas will have to be uprooted. While it would be hard to mitigate this loss, by way of compensation, it has been proposed to plant trees over an extent at least equivalent to the forest area that will be inundated. 8. Plant species that will be lost due to inundation are 279 species in total including 92 trees, 25 shrubs, 95 herbs, 4 ephiphytes, and 63 climbers/creepers. Among them there are 2 endangered, 4 vulnerable and 3 near threatened species. Out of 02 recorded endangered plant species, one herbaceous species, Cryptocoryne beckettii (Ati Udayan in Sinhala), is present on the river (Per Aru) bank. The other endangered tree species is Diospyros ebenum (Kaluwara in Sinhala and Karunkali in Tamil) found in forests and vegetation associated with reservoirs. 9. While recommending plant varieties for afforestation, care will be taken to factor in plant species which will be lost because of inundation and agro-ecology of the re-plantation areas. Availability of recommended plant types in the nurseries will also be considered. 10. A total of 316 faunal species were identified in the study area among which there were 28 endemic species, 3 proposed endemic species, 3 critically endangered species (Mycalesis visala, Euplecta colletti and Japonia vesca), 1 endangered species (Theobaldis subplicatulus), 11 vulnerable species (one bird, two butterflies, 6 mammals, and two reptiles) and 19 nearly threatened species. 11. Additional study will be conducted to ensure that the project will not adversely affect the endangered fauna species listed in Chapter III. The habitat protection measures proposed in this report, such as afforestation and endangered species monitoring, will be upgraded based on the study. For each critically endangered species and endangered species, specific protection measures will be prepared based on the survey. The NWSDB has committed to implementing these protection measures. A report on biodiversity and critical habitat protection and management will be also prepared and submitted ADB before any civil works is commenced. 12. Having assessed the key positive and negative environmental impacts and identified possible mitigation measures, the study team concludes that the project may go ahead with due consideration to the recommended mitigation measures and the monitoring mechanisms proposed.