FY2018

Study on business opportunity of High-quality Energy

Infrastructure to Overseas Business Opportunity Analysis

The Study for Restoration and Upgrading Under

Operation in the Republic of the

FINAL REPORT

FEBRUARY 2019

NIPPON KOEI CO., LTD

The Ministry of Economy, Trade and Industry

（様式２）

二次利用未承諾リスト

報告書の題名：フィリピン国：既存ダム再生・ 能力増強 事業化調査事業 ファイナルレポー ト 委託事業名 ： 経済産業省 受注事業者名 ： 日本工営株式会社

Page No. Title 1-1 Table 1.1 Main Economic Indicators in the Philippines 1-4 Table 1.2 Electrification rates in the Philippines 1-4 Table 1.3 Changes in installed capacity in the Philippines (2010 to 2015) 1-4 Table 1.4 Targets in renewable energy development in the Philippines (2011 to 2030) 1-5 Table 1.5 Changes in electricity supply framework in the Philippines Present Conditions of Hydropower Generation Dams Operation in 1-8 Table 1.6 Philippines 1-11 Figure 1.2 Geographical Location Map of and Two Project Sites 1-13 Figure 1.3 Average Temperature and Precipitation in Bohol 1-15 Figure 1.4 Active Fault Lines in Bohol 3-22 Figure 3.4 Location Map of Ambuklao and Binga Dams 3-24 Figure 3.6 Location Map of Pulangi 3-38 Figure 3.19 Location Map of Miral Dam 3-53 Figure 3.22 Hydrological and Operation Data of Bohol Project 3-54 Table 3.19 Recorded Spillout Discharge 3-54 Figure 3.23 Spillway Improvement Plan at Malinao Dam 3-58 Figure 3.25 Selection Chart of Turbine Type 3-60 Table 3.28 Maximum Flow Velocity in Penstock 3-78 Table 3.42 Planned planting area and actual planting area of each irrigation scheme 3-92 Figure 3.42 Example of Siphon Type Dredging System 4-2 Figure 4.2 Watershed and Malinao Dam 5-7 Table 5.9 Result of Economic Analysis 7-1 Figure 7.1 NIA Organization Chart 8-5 Table 8.1 Mechanical properties of duplex stainless steel (standard value: JIS G 4304) 8-6 Figure 8.4 Example of weight reduction of structural steel by applying SUS 821 L 1 8-7 Figure 8.6 Exposure test results of SUS 821 L 1 and SUS 304 8-8 Figure 8.7 Application proposal of lean duplex stainless steel PREFACE

This report represents the results of the Pre-feasibility Study, as a part of High Quality Energy Infrastructure Projects for Overseas Infrastructure Development Promotion Study, carried out by Nippon Koei, Co., Ltd.

This study titled “The Study for Restoration and Upgrading Dams Under Operation in the Republic of the Philippines” is to study present conditions of existing dams in the Republic of the Philippines, to select urgent and priority projects for dam improvement and upgrading, and to conduct pre-feasibility study. In the Study, the Bohol irrigation dams which had been constructed under the Japanese ODA was selected as the priority project, and hydropower provision of the irrigation dams as a renewable energy and redevelopment of water resources of the dams were proposed considering the Japanese advanced technologies for restoration and upgrading dams under operation. We hope that this report will help realization for the captioned project and will be a reference for beneficial use by the relevant people.

February 2019 Nippon Koei Co., Ltd.

ABBREVIATIONS

A ACIAR - Australian Center for International Agricultural Research ASEAN - Association of South-Eastern Asian ASTM - American Society for Testing and Materials AWD - Alternative wetting/drying

B BAU - Business As Usual BDO - Banco De Oro BFAR - Bureau of Fisheries and Aquatic Resources BOHECO2 - Bohol II Electric Cooperative, Inc. BOT - Build – Operate – Transfer BROT - Build – Rehabilitate – Operate – Transfer BSWM - Bureau of Soils and Water Management

C CAD - Computer – aided Design CBK - CBK Power Company Limited CCCM - Canadian Climate Center Model COP - Climate Change CPT - Critical Pitting Temperature CSC - Certificate of Stewardship Contract CSR - Community and Social Responsibility/ies

D DA/BFAR - The Department of Agriculture through the Bureau of Fisheries and Aquatic Resources DAO - DENR Administrative Order DBP - Development Bank of the Philippines DENR - Department of Environment and Natural Resources DMD - Dam Management Department (NPC) DOE - Department of Energy DPWH - Department of Public Works and Highways

E ECAs - Environmentally Critically Areas ECC - Environmental Compliance Certificate ECs - Electric Cooperatives EDP - Environment Development Project EIA - Environmental Impact Assessment EIS - Environmental Impact Statement EL. or El. - Elevation EMB - Environmental Management Bureau EOJ - Embassy of Japan EPIRA - Electric Power Industry Reform Act ERC - Energy Regulatory Commission

A-1

F FAO - Food and Agriculture Organization FIRR - Financial Internal Rate of Return FIT - Feed-In Tariff F/S - Feasibility Study FY - Fiscal Year

G GCMs - General Circulation Models GFDL - Geophysical Fluid Dynamics Laboratory GHG - Greenhouse Gas GDP - Gross Domestic Product GIS - Geographic Information System GOCC - Government Owned and Controlled Corporations GOJ - Government of Japan GOP - Government of the Philippines GREEN - Global action for Reconciling Economic growth and Environmental preservation

H ha(s). - hectare(s) HD - High Definition HEPP - Hydro Electric Power Plant HP - Home Page

I IAs - Irrigators’ Associations IBRD - International Bank for Reconstruction and Development ICLEE - Institute of Climate, Energy and Environment ICLEI - International Council for Local Environmental Initiatives IEC - International Electrotechnical Commission IEE - Initial Environmental Examination INDC - Intended Nationally Determined Contribution IP - Intellectual Property IPCC - Intergovernmental Panel on Climate Change IPP - Independent Power Producer IPPA - IPP administrator IPs - Indigenous Peoples IRR - Implementing Rules and Regulations ISELCO - Electric Cooperative, Inc.

J JBIC - Japan Bank for International Cooperation JCM - Joint Crediting Mechanism JICA - Japan International Cooperation Agency JIS - Japanese Industrial Standard JMOFA - Japan Ministry of Foreign Affair JSSC - Japanese Society Steel Construction

K KII - Key Informant Interview

A-2

L LGU(s) - Local Government Unit(s) LOI - Letter of Intent LPWA - Low Power Wide Area LTE - Long Term Evolution LTS - Local Technical Staff LWL - Low Water Level

M MARIIS - Magat Integrated Irrigation System MCM - Million Cubic Meter MEA - Multilateral Environmental Agreements MILT - Ministry of Land, Infrastructure, Transport and Tourism (Japan) MMDA - Metropolitan Manila Development Authority MOA(s) - Memorandum of Agreement(s) MOE - Ministry of Environment

N NCAR - National Center for Atmospheric Research NETIS - New Technology Information System NGO(s) - Non-Government Unit(s) NIA - National Irrigation Administration NIPAS - National Integrated Protected Area System’s NPC - National Power Corporation NPV - Net Present Value NREB - National Renewable Energy Board NWL - Normal Water Level NWRB - National Water Resources Board (Philippines)

O O&M or O/M - Operations and Maintenance ODA - Official Development Assistance OECD - Organization for Economic Cooperation and Development OECF - Overseas Economic Cooperation Fund

P PAGASA - Philippine Atmospheric, Geophysical and Astronomical Services Administration PEISS - Philippine Environmental Impact System PES - Power Engineering Services PDRRMC - Provincial Disaster Risk Reduction and Management Council PHP - Philippine peso POs - People’s Organizations PPA - Purchase Price Allocation PPP - Private Partnership Projects PSA - Philippine Standard Agency PSIF - Private Sector Investment Finance PSALM - Power Sector Assets and Liabilities Management Corporation

A-3

R RA - Republic Acts RDRRMC - Philippines National Disaster Risk Reduction and Management Council RO - Regional Office ROW - Right of Way RPS - Renewable Portfolio Standard RSPL - Rajah Sikatuna Protected Landscape

S SALT - Sloping Agricultural Land Technology SAPS - Special Assistance for Project Sustainability SCF - Standard Conversion Factor SRIP - Small Reservoir Irrigation Project SN - Statkraft Norfund SNAP - SN Aboitiz Power, Inc. SPC - Special Purpose Company SRES - Special Report on Emission Scenarios SRIP - Small Reservoir Irrigation Project STAT - Statistic STEP - Special Terms for Economic Partnership SUS - Steel Special Use Stainless SWCF - Soil and Water Conservation Foundation SXGA - Super Xtended Graphics Array

T TEPSO - Tokyo Electric Power Services Co., Ltd. TOR - Term of Reference

U UKMO - United Kingdom Meteorological Office UPMO - Unified Project Management Office

V VAT - Value Added Tax VGA - Video Graphics Array

W WACC - Weighted Average Cost of Capital WESM - Wholesale Electricity Spot Market

X XRAIN - Exterded Radar Infromation Network

A-4

Unit

Length Money mm = millimeter PHP = Philippine Peso cm = centimeter JPY = Japanese Yen m = meter USD = U.S. Dollar km = kilometer

Area Direction ha = hectare N = North m2 = square meter E = East km2 = square kilometer S = South W = West Volume NE = North-East NW = North-West 1, lit = liter SE = South-East m3 = cubic meter SW = South-West m3/s, cms = cubic meter per second MCM = million cubic meter m3/d, cmd = cubic meter per day

Weight Others mg = milligram % = percent g = gram ° = degree kg = kilogram ' = minute t = ton " = second MT = metric ton °C = degree Celsius cap. = capital Time md = man-day mil. = million sec = second no. = number hr = hour pers. = person d = day mmho = micromho yr = year ppm = parts per million ppb = parts per billion Energy lpcd = litter per capita per day kcal = Kilocalorie kW = kilowatt MW = megawatt kWh = kilowatt-hour GWh = gigawatt-hour

A-5

Draft Final Report Main Report Table of Contents

Table of Contents Location Map Abbreviation Table of Contents List of Tables List of Figures Appendix Summary

CHAPTER 1 Outline of the Targeting Country and Sector ...... 1-1 1.1 Financial and Economic Conditions of the Philippines ...... 1-1 1.2 Outline of the Target Sector of the Project ...... 1-1 1.2.1 Japan's Strategy for Exporting Infrastructure Systems, and Strategies for Expanding Overseas Business in Individual Sectors ...... 1-1 1.2.2 Related Policies in the Philippines ...... 1-3 1.2.3 Needs of Recipient Country ...... 1-7 1.2.4 Analysis of the Advantages and Disadvantages of Rival Country Companies and Japanese Companies in Related Sectors ...... 1-8 1.3 Present Condition of the Study Area ...... 1-10 1.3.1 Existing Dams in the Philippines ...... 1-10 1.3.2 Present Conditions of the Pre-Feasibility Study Area ...... 1-10 CHAPTER 2 Methodology of the Study ...... 2-1 2.1 Outline of the Study ...... 2-1 2.2 Methodology and Organization of the Study ...... 2-2 2.2.1 Work Flow of the Study ...... 2-2 2.2.2 Organization of the Study Team ...... 2-3 2.3 Implementation Schedule of the Study ...... 2-3 2.3.1 Work Schedule of the Study ...... 2-3 2.3.2 The First Field Survey ...... 2-4 2.3.3 The Second Field Survey ...... 2-5 CHAPTER 3 Project Components and Technical Study ...... 3-1 3.1 Background of the Project ...... 3-1 3.2 Basic Approach of the Study ...... 3-1 3.2.1 Key Considerations and Issues on the Study ...... 3-1 3.2.2 Basic Approaches for the Project Components ...... 3-4 3.3 Outline of the Project ...... 3-6 3.3.1 The Project Proposed ...... 3-6 3.3.2 Purpose of the Project ...... 3-6

Nippon Koei Co., Ltd. i The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Main Report Table of Contents

3.3.3 Outline of the Project ...... 3-6 3.4 Items of Necessary Studies ...... 3-8 3.4.1 Project Selection Study ...... 3-8 3.4.2 Basic Design of the Selected Project ...... 3-51 3.4.3 Study for Hydropower Provision in Bohol Irrigation Project ...... 3-55 3.4.4 Consideration Concerning Operation Improvement of 3 Existing Dams ...... 3-78 3.4.5 Study on Sediment Management ...... 3-87 CHAPTER 4 Social and Environmental Study ...... 4-1 4.1 Physical Environment ...... 4-1 4.1.2 Biological Environment ...... 4-4 4.2 Environmental and Social Impact Assessment and Mitigating Measures ...... 4-5 4.3 Laws and Regulations related to the Environment and Social Concerns ...... 4-9 4.3.1 Environmental/Social Regulatory Compliance ...... 4-9 4.3.2 The Environmental and Natural Resource Management Mandates of the LGU ...... 4-10 4.3.3 Specific laws, Policies and Guidelines, Ordinances in Bohol ...... 4-11 4.4 Institutional and Administrative Framework ...... 4-12 CHAPTER 5 Financial and Economic Viability ...... 5-1 5.1 Cost Estimation of the Project ...... 5-1 5.2 Preliminary Financial and Economic Analysis ...... 5-2 5.2.1 Basic Assumptions ...... 5-2 5.2.2 Project Cost ...... 5-2 5.2.3 Financial Analysis ...... 5-4 5.2.4 Economic Analysis ...... 5-5 CHAPTER 6 Implementation Schedule of the project ...... 6-1 CHAPTER 7 Capability of Implmenting Agency ...... 7-1 7.1 Outline of Implementing Agency ...... 7-1 7.2 Organization for Project Implementation ...... 7-1 7.3 Capacity of Implementing Agency and Necessary Measures ...... 7-2 CHAPTER 8 Advantage of Technology and Other Aspects of Japanese Companies ...... 8-1 8.1 International Competitiveness and Possibility of Japanese Companies' Getting Orders for Projects (by Equipment, Goods and Services) ...... 8-1 8.1.1 Analysis of Strengths and Weaknesses of Japanese Companies and Overseas Competitors in Related Sector ……………………………………………………………………………………………………...8-1 8.1.2 International Competitiveness of Japanese Companies in Related Sector ...... 8-1 8.1.3 Application of Japanese Technologies to Related Sector ...... 8-2 8.1.4 Examples of Japanese Technologies Applied to Related Sectors ...... 8-3 8.1.5 Application of New Material (Duplex Stainless Steel） ...... 8-5 8.2 Description and Costs of Main Equipment and Materials Expected to Be Procured from Japan ...... 8-10 8.2.1 Technologies for the reconstruction and increase in dam capacities ...... 8-10 Nippon Koei Co., Ltd. ii The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Main Report Table of Contents

8.3 Policies Necessary for Promoting Japanese Companies' Getting Orders ...... 8-12 8.3.1 Technologies for Restoration and Upgrading of Dams ...... 8-12 8.3.2 Application of Mew Materials ...... 8-13 CHAPTER 9 Applicable Fund Source ...... 9-1 9.1 Applicable Project Scheme...... 9-1 9.1.1 Rehabilitation of Existing Dams owned by NIA (example: Lupao Dam in Ruzon) ...... 9-1 9.1.2 Construction of Small Scale Hydro Power Generation Project (example: Malinao, Bayongan, Capayas Dams in Bohol) ...... 9-1 9.1.3 Rehabilitation of Existing Dams owned by Private Companies (example: Ambuklao and in Ruzon) ...... 9-2 9.2 Expected Fund Source of the Project ...... 9-3 9.2.1 Applicable Fund Source for the Project implemented by Public Organizations ...... 9-3 9.2.2 Applicable Fund Source for the Project implemented by Private Entities ...... 9-3 9.2.3 Other Incentives from the Government of the Philippines ...... 9-5 CHAPTER 10 Action Plan and Issues for Project Implementation ...... 10-1 10.1 Actions taken to Request for Japanese ODA Project ...... 10-1 10.1.1 Conclusion of the Study ...... 10-1 10.1.2 Work Shop of the Study ...... 10-1 10.1.3 Meetings with Concerned Agencies for Endorsement of Japanese ODA ...... 10-1 10.2 Action Plan and Issues for Request of Japanese ODA Project in Future and Horizontal Development to Other Countries ...... 10-1 10.2.1 Action Plan and Issues for Request of Japanese ODA Project in Future ...... 10-1 10.2.2 Horizontal Development to Other Countries...... 10-2

Nippon Koei Co., Ltd. iii The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Main Report Table of Contents List of Tables page Table 1.1 Main Economic Indicators in the Philippines ...... 1-1 Table 1.2 Electrification rates in the Philippines ...... 1-4 Table 1.3 Changes in installed capacity in the Philippines (2010 to 2015) ...... 1-4 Table 1.4 Targets in renewable energy development in the Philippines (2011 to 2030) ...... 1-4 Table 1.5 Changes in electricity supply framework in the Philippines ...... 1-5 Table 1.6 Present Conditions of Hydropower Generation Dams Operation in Philippines ...... 1-8 Table 2.1 Schedule of the first field survey ...... 2-4 Table 2.2 Schedule of the Second Field Survey ...... 2-5 Table 3.1 Relation between the Study and Energy Policy and Infrastructure Development of Japan .... 3-2 Table 3.2 Integrity with Energy Policy of the Philippines and Beneficiaries ...... 3-2 Table 3.3 Considerations and Approaches of the Study for Application of Japanese Advanced Technology ………………………………………………………………………………………………..3-2 Table 3.4 Category of Group of Objective Dams ...... 3-4 Table 3.5 List of Data Collection ...... 3-8 Table 3.6 Outline of Questionnaire ...... 3-12 Table 3.7 List of Long-listed Dams (1/2) ...... 3-14 Table 3.8 List of Long-listed Dams (2/2) ...... 3-15 Table 3.9 Summary of First Screening of Objective Dams ...... 3-16 Table 3.10 List of Magat Complex HEPPs ...... 3-26 Table 3.11 Main Findings of Site Reconnaissance (Reservoir Sedimentation) ...... 3-40 Table 3.12 Main Findings of Site Reconnaissance (Dam Safety) ...... 3-41 Table 3.13 Main Findings of Site Reconnaissance (Condition of Operation and Maintenance) ...... 3-43 Table 3.14 Main Findings of Site Reconnaissance (Social and Environmental) ...... 3-45 Table 3.15 Main Findings of Site Reconnaissance (Adaptation of Japanese Technology) ...... 3-47 Table 3.16 Main Findings of Site Reconnaissance (Possibility of Financial of Japanese ODA)...... 3-47 Table 3.17 Result of Second Screening (tentative) ...... 3-49 Table 3.18 Collected Data of Dam Operation Records...... 3-51 Table 3.19 Recorded Spillout Discharge ...... 3-54 Table 3.20 Operation Patterns for Power Generation ...... 3-56 Table 3.21 Power Discharge at Malinao Dam ...... 3-57 Table 3.22 Reservoir Water Level and Tail Water Level at Malinao Dam ...... 3-57 Table 3.23 Power Discharge at Diversion Chute ...... 3-57 Table 3.24 Reservoir Water Level and Tail Water Level at Bayongan Dam ...... 3-58 Table 3.25 Power Discharge at Bayongan Dam ...... 3-58 Table 3.26 Selected Turbine Type ...... 3-59 Table 3.27 Number of Pole and Relative Velocity of Generator ...... 3-59 Table 3.28 Maximum Flow Velocity in Penstock ...... 3-60

Nippon Koei Co., Ltd. iv The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Main Report Table of Contents

Table 3.29 Designed Pipe Diameter ...... 3-60 Table 3.30 Calculation Results at Malinao (1) ...... 3-62 Table 3.31 Calculation Results at Malinao Power Station (2) ...... 3-63 Table 3.32 Calculation Results at Diversion Chute Power Station (1) ...... 3-65 Table 3.33 Calculation Results at Diversion Chute Power Station (2) ...... 3-66 Table 3.34 Calculation Results at Bayongan Power Station (1) ...... 3-68 Table 3.35 Calculation Results at Bayongan Power Station (2) ...... 3-69 Table 3.36 Summary of Power Simulation ...... 3-71 Table 3.37 Power Dimensions and Major Elements of Power Stations ...... 3-73 Table 3.38 Approximate Work Quantities ...... 3-75 Table 3.39 Annual Operation and Maintenance Cost ...... 3-76 Table 3.40 Annual Operation and Maintenance Cost ...... 3-76 Table 3.41 Benefit for Reduction of CO2 Emission of Each Power Station ...... 3-77 Table 3.42 Planned planting area and actual planting area of each irrigation scheme ...... 3-78 Table 3.43 Configuration of Proposed Irrigation Telemetering System Adopting the Japanese Technology ...... 3-80 Table 3.44 Monthly Rainfall, Evaporation and Inflow and Cropping Pattern ...... 3-82 Table 3.45 Benefits by Improving Irrigation Operation ...... 3-86 Table 4.1 Assessment of Potential Social Environmental Impacts and Mitigation Measures ...... 4-6 Table 5.1 Direct Construction Cost of Diversion Chute HEPP ...... 5-1 Table 5.2 Basic Assumptions for Financial and Economic Analysis ...... 5-2 Table 5.3 Financial Cost and Economic Cost of Initial Investment Cost ...... 5-3 Table 5.4 Financial Cost and Economic Cost of O&M Cost ...... 5-3 Table 5.5 Revenue of Power Generation ...... 5-4 Table 5.6 Result of Financial Analysis ...... 5-5 Table 5.7 Indicators for Economic Benefit of Increase of Paddy Production ...... 5-6 Table 5.9 Result of Economic Analysis ...... 5-7 Table 6.1 Implementation Schedule of Improvement of Malina Dam Spillway...... 6-1 Table 6.2 Implementation Schedule of the Project ...... 6-1 Table 8.1 Mechanical properties of duplex stainless steel (standard value: JIS G 4304) ...... 8-5 Table 8.2 Results of application of lean duplex stainless steel to water gates in Japan ...... 8-9 Table 8.3 Equipment and materials expected to be procured from Japan ...... 8-10 Table 9.1 Expected Fund Source ...... 9-3

Nippon Koei Co., Ltd. v The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Main Report Table of Contents List of Figures page Figure 1.1 Characteristics of Alloy-saving duplex stainless steel (high strength and lightness) ...... 1-9 Figure 1.2 Geographical Location Map of Bohol and Two Project Sites ...... 1-11 Figure 1.3 Average Temperature and Precipitation in Bohol ...... 1-13 Figure 1.4 Active Fault Lines in Bohol ...... 1-15 Figure 2.1 Work Flow of the Study ...... 2-2 Figure 2.2 Organization Chart of the Study Team ...... 2-3 Figure 2.3 Work Schedule of the Study...... 2-3 Figure 3.1 Location Map of Shor-Listed Dams ...... 3-18 Figure 3.2 Main Items Investigated during Site Reconnaissance ...... 3-19 Figure 3.3 Reservoir Sedimentation in Binga Dam ...... 3-21 Figure 3.4 Location Map of Ambuklao and Binga Dams...... 3-22 Figure 3.5 Site Photos of Ambuklao and Binga Dams ...... 3-23 Figure 3.6 Location Map of Pulangi Dam ...... 3-24 Figure 3.7 Site Photos of Pulangi Dam ...... 3-25 Figure 3.8 Location Map of Complex and HEPPs ...... 3-27 Figure 3.9 Site Photos of Magat Complex HEPPs ...... 3-28 Figure 3.10 Profile of Dams in Bohol Irrigation Project ...... 3-29 Figure 3.11 Layout Plan of Malinao Dam...... 3-30 Figure 3.12 Site Photos of Malinao Dam ...... 3-31 Figure 3.13 Site Photos of Bayongan Dam ...... 3-32 Figure 3.14 Site Photos of Capayas Dam ...... 3-33 Figure 3.15 Location Map of Lupao Dam...... 3-35 Figure 3.16 Site Photos of Lupao Dam ...... 3-35 Figure 3.17 Location Map of Tangilad Dam ...... 3-37 Figure 3.18 Site Photos of Tangilad Dam ...... 3-37 Figure 3.19 Location Map of Miral Dam ...... 3-38 Figure 3.20 Site Photos of Miral Dam ...... 3-39 Figure 3.21 Project Outline ...... 3-52 Figure 3.22 Hydrological and Operation Data of Bohol Project ...... 3-53 Figure 3.23 Spillway Improvement Plan at Malinao Dam ...... 3-54 Figure 3.24 Example of Dam Outflow Pattern (above: Pattern A, below: Pattern D)...... 3-56 Figure 3.25 Selection Chart of Turbine Type ...... 3-58 Figure 3.26 Turbine Efficiency ...... 3-59 Figure 3.27 Generator Efficiency ...... 3-60 Figure 3.28 Maximum Power Output, Annual Energy, Construction Cost and Unit Construction Cost at Malinao Power Station ...... 3-64 Figure 3.29 Maximum Power Output, Annual Energy, Construction Cost and Unit Construction Cost at

Nippon Koei Co., Ltd. vi The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Main Report Table of Contents

Diversion Chute Power Station ...... 3-67 Figure 3.30 Maximum Power Output, Annual Energy, Construction Cost and Unit Construction Cost at Bayongan Power Station ...... 3-70 Figure 3.31 Layout Plan of Diversion Chute Hydro Electric Power Plant ...... 3-74 Figure 3.32 Layout Image of Diversion Chute Hydro Electric Power Plant ...... 3-75 Figure 3.33 Effect to Reduce Spillway Outflow by Improvement of Malinao Dam Operation ...... 3-83 Figure 3.34 Sediment Condition at Malinao Dam ...... 3-87 Figure 3.35 Daily reservoir water level and daily inflow discharge at Malinao Dam ...... 3-89 Figure 3.38 Estimated Sediment Figure ...... 3-89 Figure 3.39 Reservoir Volume Curve and Location of Sand Flush Gate ...... 3-90 Figure 3.40 Overflow Discharge at the Sand Flush Gate ...... 3-90 Figure 3.41 Example of Sand Flushing Simulation (Operation D) ...... 3-91 Figure 3.42 Example of Siphon Type Dredging System ...... 3-92 Figure 4.1 Seven Major River Basins in Bohol Considered as Potential Sources of Water Supply ...... 4-1 Figure 4.2 Inabanga Watershed and Malinao Dam Reservoir ...... 4-2 Figure 7.1 NIA Organization Chart ...... 7-1 Figure 7.2 Organization Chart of NIA Region VII Office ...... 7-2 Figure 8.1 Application of Japanese Technologies in Dam Sector (left: a dam with power generation, right: a dam without power generation) ...... 8-3 Figure 8.2 Schematic drawing showing the outline of countermeasure against sedimentation at Wonogiri dam in Indonesia (sediment dam and sand trap construction) ...... 8-3 Figure 8.3 Nam Ngum No. 1 hydropower station expansion project (left: layout of the 6th generator, right: double-sheet-pile coffer dam structure under construction) ...... 8-4 Figure 8.4 Example of weight reduction of structural steel by applying SUS 821 L 1 ...... 8-6 Figure 8.5 Positioning of duplex stainless steel ...... 8-7 Figure 8.6 Exposure test results of SUS 821 L 1 and SUS 304 ...... 8-7 Figure 8.7 Application proposal of lean duplex stainless steel ...... 8-8 Figure 8.8 Example of a flood gate that applied lean duplex stainless steel ...... 8-10 Figure 9.1 Project Scheme for Rehabilitation of Existing Dams owned by NIA ...... 9-1 Figure 9.2 Project Scheme for Construction of Small Scale Hydro Power Generation System in Bohol Island 9-2 Figure 9.3 Project Scheme for Rehabilitation of Existing Dams owned by Private Companies ...... 9-2 Table 9.1 Expected Fund Source ...... 9-3

Nippon Koei Co., Ltd. vii The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Main Report Table of Contents

Appendix

1. Location Map of Existing Dam and Hydro Power Plant 2. List of Existing Dam and Hydro Power Plant 3. Photos of Dams 4. Endorsement Letter from NIA xxxxxxxxxxxxxxxxxxxxxxxxx 6. Questionnaire and Answers 7. Dam Operation Data Xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Nippon Koei Co., Ltd. viii The Study for Restoration and Upgrading Dams Under Operation in the Philippines Summary

1. Background of the Project

The high dams in the Philippines are categorized into two; one is the multipurpose and the irrigation dams managed by the National Irrigation Administration (NIA）and another is the hydropower dedicated dams managed by the National Power Corporation (NPC). The operation and maintenance of most of the NPC dams have already been transferred to consortiums of private companies. A few decades after construction of these dams, dam facilities and sedimentation of have already posed problems to their operations, causing the obstructions of water supply and operation of hydropower generation It is predicted that the dam function will be lost completely and water supply and hydropower generation will be stopped. As seen in the above, plan formulation and implementation of the study for rehabilitation and restoration of dams are urgent issues for most of the exiting dams owned by NIA, NPC and Consortium. Comprehensive studies that would determine the reservoir sedimentation condition and soundness of the dam body and its related facilities in order to formulate the rehabilitation plan for succeeding future rehabilitation works need to be undertaken.

2. Basic Approach of the Selection of Study

In this study, the most required dams were selected among dams above, and The Study Team conducted Pre F/S. Figure 1 shows the selection process and evaluation terms. First and second screenings were conducted for 58 dams, which are selected from the questionnaires submitted from NIA and NPC. First screening was based on six terms, while second screening were 8 terms. Second screening was conducted for dams that were selected thorough the first screening and The Study Team carried out the field survey for them.

I． Project Selection Study i. Site safety ii. Year after construction (sedimentation condition) iii. Actualized problems I.1 Data Collection iv. Socio-environmental issues v. Condition of rural Evaluation electrification, and Long-list (58 Dams) Criteria 1 vi. Condition of reservoir operation I.2 1st Screening i. Reservoir sedimentation Short-list (10 Dams) condition, ii. Safety of the dam body, iii. Conditions of O&M, I.3 Additional Data collection iv. Socio-environmental issues, Evaluation v. Adaptability of Japanese Site Reconnaissance Criteria 2 advanced technology, vi. Economic viability nd (preliminary), I.4 2 Screening vii. Possibility of financial of JICA ODA loan and JBIC loan, and viii. Reduction efficiency of energy Selection of a Dam for Pre F/S sourced CO2

Source: The Study Team Figure 1 Selection process and evaluation terms

Nippon Koei Co., Ltd. 1 The Study for Restoration and Upgrading Dams Under Operation in the Philippines

3. Outline of the Project

3-1. The Project Proposed As the results of the study as mentioned in Section 3.4, “The Project for Restoration and Upgrading Dams in Bohol” is proposed for the pre-feasibility study considering the following reasons. - selected as the highest priority through the project screening among the short-listed dams - there is a room to improve dam operation because of a lot of spill outs under present operation - needs for countermeasure for reservoir sedimentation - NIA has a plan to improve the existing spillway - potential for provision of new hydro-electric power plant (HEPP) to the existing dams which are utilized for irrigation water supply only, but not for hydro-electric power generation - consistent with the electrification policy in Bohol. - increase of demand for eco-energy development There are 3 dams (Malinao, Bayongan and Capayas dam) in the study area. Figure 2 shows location of them.

Source: The Study Team Figure 2 Location of Malinao, Bayongan and Capayas dam in Bohol

The Study Team considered the following three (3) components;

1) Mini hydro-electric power developments in existing irrigation dams in Bohol

2) Improvement of operation of existing irrigation dams to reduce spill out and wasting water use

3) Countermeasures for reservoir sedimentation in Malinao Dam

Nippon Koei Co., Ltd. 2 The Study for Restoration and Upgrading Dams Under Operation in the Philippines

4. Consideration Result

4-1. Study for Hydropower Provision in Bohol Irrigation Project

Hydropower facilities are not provided at Bohol Irrigation Project. This section discusses technical study of the hydropower provision at Malinao Dam, Diversion Chute and Bayongan Dam. This section studies the following items, i) reviewing the record of reservoir operation (reservoir water level, reservoir inflow, reservoir outflow), ii) maximum power output, annual generation power, construction cost depending on turbine discharge, iii) economical project scale based on indicator of kWh construction cost. The current irrigation discharge depends on weather condition, farm season (irrigating or harvesting season). No irrigation water is discharged for several months because of no demand. Hydropower facility would consume the water even in no demand season for irrigation, and spillout water from the dam would be reduced. The reservoir water level, full supply level, will be raised by 2.0 m height by provision of rubber gate at the overflow weir of the spillway at Malinao Dam. This water level rising increases the reservoir volume from 6.0 mil. m3 to 8.0 mil. m3. The hydropower study examines two cases, the current reservoir volume and future reservoir volume after raising at Malinao Dam. Four operation patterns, A, B, C, and D are established for the simulation of power generation, and are discussed below. Table1 Operation Patterns for Power Generation Operation Pattern Reservoir Volume Outflow Pattern A 6.0MCM (Current) Current Operation Pattern B 6.0MCM (Current) Minimum discharge1.0m3/s Pattern C 8.0MCM (Increased) Minimum discharge 1.0m3/s Pattern D 8.0MCM (Increased) Minimum discharge 2.0m3/s Source: The Study Team

As the result of the consideration for each hydropower plant at Malinao, Diversion Chute and Bayongan, The Study Team concluded operation pattern D is the most appropriate case. Table 2 shows power dimension and major elements of power stations.

Nippon Koei Co., Ltd. 3 The Study for Restoration and Upgrading Dams Under Operation in the Philippines

Table 2 Power Dimensions and Major Elements of Power Stations Diversion Item Malinao Bayongan Chute Basic Plan for Hydropower Generation Maximum power output kW 289.0 1,038.0 226.0 Maximum power discharge m3/s 5.0 2.0 2.5 Maximum effective head m 7.8 67.2 12.3 Annual generation MWh 847.0 4,491.0 630.0 Head pond Width m - 50.0 - Length m - 100.0 - Depth m - 5.0 - Effective depth m - 4.0 - Effective storage m3 - 20,000 - Penstock Diameter m 2.0 1.0 1.5 Length m 25.0 293.0 25.0 Number of anchor block nos 3 14 3 Power House Width m 12.0 14.0 12.0 Length m 10.0 10.0 10.0 Height m 4.0 4.0 4.0 Tailrace Width m 3.0 3.0 3.0 Height m 2.0 2.0 2.0 Length m 30.0 18.0 30.0 Mechanical Equipment X=Q*He2/3*n1/2 - 19.67 33.06 13.32 Electric Equipment X=Pmax/He1/2 - 103.48 126.62 64.44 Source: The Study Team

4-2. Consideration concerning operation improvement of 3 existing dams

In this study, improvement of dam operation was suggested as above. Two (2) components were considered as related matters. a) Installation of Irrigation Telemeter System Irrigation plan can be formulated theoretically, but in order to make sure this as a feasible plan, it is preferable to establish an irrigation water management system, and we have to constantly monitor weather, canal water level, farming situation (for grasping water requirement of the crop) in order to eliminate ineffective water as much as possible by comparing between necessary amount of water and actual distributing water amount. In this study, The Study Team suggested to install the irrigation telemeter system. It can constantly manage following items, dam reservoir volume, the amount of water discharged from the irrigation intake facility of dam, the amount of water discharged from the spillway of dam, the water discharge of each branch to the secondary canal. b) Expansion of irrigation area when 1.0 m3/sec is taken as Diversion Water to Bayongan irrigation scheme

Nippon Koei Co., Ltd. 4 The Study for Restoration and Upgrading Dams Under Operation in the Philippines

When 1.0 m3/sec is taken as Diversion Water to Bayongan, development effects are expected as bolow; 1） Current irrigation area is lower than the plan, it can be restored to the plan by improvement of operation 2） By this operation, the amount of Bayongan dam inflow will increase. As the effect of using this dam reservoir the irrigation area can be increased. As this effect, the following two effects are considered. 2-1) Planting for the third term in existing Bayongan irrigation scheme during non-irrigation period 2-2) Planting for new irrigation development in Bayongan irrigation scheme during irrigation period

4-3. Study on Sediment Management

Sediment at Malinao Dam is now progressing, and it is a key issue of dam management. The sediment material in front of the intake structure does not provide harmful effect, but trashes float in front of the intake structure and trash screen is clogged. Reservoir sediment survey was not executed at Malinao Dam. It is difficult to estimate the sediment volume and progress rate. Sediment volume was estimated using Brune formula and the assumption that specific sediment load as1 mm/yr, which was applied for Bayongan Dam construction. As the result, Sediment volume is estimated at 2.08 MCM (=0.1388 x 20 x 0.75). Total reservoir volume of Malinao Dam is at 6.0 MCM, the sediment rate is at about 30 % (=2.08/6.0). Applicable countermeasures for sedimentation of Malinao Dam are listed below. i) Sediment inflow countermeasure: Check dam, floating log blockage structure, catchment conservation ii) Sediment outflow countermeasure: Sand flush gate at spillway, reservoir dewatering to accelerate sediment dry excavation, siphon sand flush iii) Trash inflow countermeasure: Trash boom, trash removing machine iv) Measurement method: Echo sounding, sediment measurement, sediment simulation analysis a) Countermeasure Study for Sedimentation Malinao reservoir has so high rotating rate as 25.4 that the reservoir can be impound quickly after reservoir empty. Therefore, the reservoir is dewatered intentionally, and sediment can be flushed by flow tractive force. Initial cost is high to construct sand flush gate, but maintenance cost is less. This report studies the followings. Irrigation demand is null from 15 April to 30 June. In this period, the reservoir is dewatered to low water level (LWL) of the reservoir with reservoir volume of 1 MCM, the reservoir becomes like original river morphology. Sand flush gate shall be opened at the time of small scale floods to flush out the sediment. The impacts to irrigation work by this operation are examined.

Nippon Koei Co., Ltd. 5 The Study for Restoration and Upgrading Dams Under Operation in the Philippines

ShoulderDelta of sedimentation delta New Sediment HWL 154.40 Sand Flush Gate Average Water Level EL.151NWL.2 152.00 Flushing Gate

EL 147.00

EL 137.00

Malinao 156.00

154.00 Sand Flush Gate NWLHWL, 152 152 152.00

150.00

148.00 LWLLWL, 146146 146.00

144.00 Water Level(EL.m) 142.00

140.00 Intake Sill 138 138.00

136.00 1,000,000 6,000,000 0 1,000,000 2,000,000 3,000,000 4,000,000 5,000,000 6,000,000 7,000,000 Reservior Volume(m3)

Source: The Study Team Figure 3 Location and schematic figure of Sand Flush Gate

Reservoir water level is generally recovered after sand flush operation even in Operation A and D, the reservoir water level from 1 July to 14 April in the irrigation period is not below the low water level. Sand flush operation does not prove harmful effects to irrigation operation. Study on flood forecasting is recommended to avoid surely the risk of non-irrigation. Moreover, three dimension analysis of sediment flow is recommended with measurement investigation of sediment concentration, sediment particle size, sediment figure and others. b) Dredging in Surrounding Area of the Intake The construction of the sediment flushing gate is the measure to realize sustainable reservoir operation by removal of the sediment deposits within the effective storage volume above LWL.142.0. On the other hand, the sill elevation of the intake tower of the Malinao Dam is El. 137.5m that is lower than the LWL 142.0. To remove the sediment deposits in the surrounding area of the intake needs another measure. For example, a siphon type dredging system using the effective head difference of the dam would be one of the measures for removal of the sediment deposits in the surrounding area of the intake because of advantage of reduction of operation and maintenance cost.

4-4. Finacial and Economical Viability a) Financial Analysis Preliminary financial analysis is conducted for each small hydropower provision project in Bohol by estimating the cost and revenue. The FIRR value is higher for Diversion Chute, but the value is only xxx% under normal case. If 30% of initial investment cost is subsidized by JCM system, the FIRR increased up to xxx%. Those values are still lower than the WACC (8.68%), and other cost reduction or financial support is expected to make the project financially feasible.

Nippon Koei Co., Ltd. 6 The Study for Restoration and Upgrading Dams Under Operation in the Philippines

Table 3 Result of Financial Analysis Base Case 30% JCM subsidy Case Dam FIRR NPV FIRR NPV Malinao xxxx xxxxxxxxxxxxx xxxx xxxxxxxxxxxxx Diversion Chute xxxx xxxxxxxxxxxxx xxxx xxxxxxxxxxxxx Bayongan xxxx xxxxxxxxxxxxx xxxx xxxxxxxxxxxxx Total xxxx xxxxxxxxxxxxx xxxx xxxxxxxxxxxxx Source: The Study Team b) Economic Analysis Economic analysis were conducted by three cases as below; Case 1 : Power generation (minimum discharge of 1m3) + Incremental irrigated area (rehabilitation of planned area, 2,147ha) Case 2 : Power generation (minimum discharge of 2m3) + Incremental irrigated area (Case1 + triple cropping of existing area, 2,759ha) Case 3 : Power generation (minimum discharge of 2m3) + Incremental irrigated area (Case2 + new irrigated area, 3,983ha) Comparing the estimated economic cost and economic benefits, the EIRR under three alternative cases become as shown in the table below. EIRR of Case1 is lower than the hurdle rate at 10%, but the EIRR values surpass the 10% under Case2 and Case3 and the project is considered as economically viable. Table 4 Result of Economic Analysis Total Project EIRR NPV B/C Case1 (1m3) xxxx xxxxxxxxxxxxx xxxx Case2 (2m3) xxxx xxxxxxxxxxxxx xxxx Case3 (2m3) xxxx xxxxxxxxxxxxx xxxx Source: The Study Team

4-5. Application of Japanese Technologies to Related Sector

As previously mentioned, the dams in the Philippines are classified into two main types, one with power generation and the other without power generation. The Japanese technologies that can be individually applied to the dams with power generation are dam inspection and diagnostic technologies, research and construction technologies while maintaining dam operation, recycling of existing facilities and proximity construction, sedimentation protection technology, construction technologies associated with raising dam heights and expanding water discharge facilities. In addition to these individual technologies, there is a possibility of presenting a package proposal integrating a financial scheme, a post-construction rehabilitation program, and improvement in maintenance and management capability. In contrast, the Japanese technologies that can be individually applied to the dams without power generation (reconstruction of irrigation dams) are small hydropower generation technologies (promotion of downsizing

Nippon Koei Co., Ltd. 7 The Study for Restoration and Upgrading Dams Under Operation in the Philippines and streamlining) and new materials (for maintenance-free operation, improvement in abrasion resistance and weight saving). A package proposal is also possible.

4-6. Applicable Fund Source

Applicable fund sources and schemes for the rehabilitation project of existing dams are as below; a) Rehabilitation of Existing Dams owned by NIA (example: Lupao Dam in Ruzon) The dams are operated and owned by NIA, hence the use of ODA loan provided by concessional conditions is expected for the project. The budget for construction and procurement would be provided from the government by sub-lent or subsidy through DA. b) Construction of Small Scale Hydro Power Generation Project (example: Malinao, Bayongan, Capayas Dams in Bohol) Project scheme of small scale hydro power generation system in Bohol island is shown below. Japanese and local investors create SPC for the project. Generated electricity by the hydro power generation system is sold to ECs (Electric Cooperatives) which distribute electricity to users. The sold unit tariff is determined by applying the FIT (Feed-In Tariff) or the rate which is mutually agreed between SPC and EC. The project could be financed by loan and equity. The loan part is lent by the local banks and international banks such as JICA/JBIC which provide under concessional conditions. The equity is invested by local and Japanese investors. In addition, there is a possibility that 50% of equipment cost (at maximum) is subsidized by JCM framework to promote reduction of greenhouse gas emission supported by the Japanese MOE.

Electric Cooperatives

(ECs)

Electricity Electricity Supply Charge

TSL, PSIF Loan Other Commercial JICA Banks

TSL SPC Equity JBIC Local Investors

JCM Japanese Investors MOE Material/ Construction Machines Works

Japanese Japanese/Local Material/Machine Construction Supplier Company

Source: The Study Team Figure 4 Project Scheme for Construction of Small Scale Hydro Power Generation System in Bohol Island

Nippon Koei Co., Ltd. 8 The Study for Restoration and Upgrading Dams Under Operation in the Philippines c) Rehabilitation of Existing Dams owned by Private Companies (example: Ambuklao and Binga Dam in Ruzon) The fund source used for the existing dams which are owned and operated by private companies is limited to Two Stem Loan provided by JICA and JBIC. The rest of the fund is provided by the loans from commercial banks. The Japanese construction companies and material/machine companies could participate in the project for the purpose of construction and procurement.

5. Conclusion and Action Plan

The proposed project of “Improvement of Water Resources Management of Bohol Irrigation Dams” will contribute for redevelopment of water resources through i) the improvement of dam operation by installation of irrigation water management system and ii) the improvement of the Malinao Dam Spillway (raising of NWL by 2 m by installation of rubber gate) studied by NIA that enable to reduce the excess volume of spillway outflow under current operation. The proposed project is preliminary evaluated economically feasible and social and environmentally acceptable. On the other hand, another proposed project of “Hydropower Provision in Bohol Irrigation System” is preliminary evaluated the financial viabilities is low because of low efficiency of power generation due to irrigation dependable water and exclusion of income increase by irrigation water development as per the present regulation in the Philippines. Full-scale feasibility study shall be implemented based on more detailed investigation for dam operation, design and financial scheme.

Action plan is expected as below;

① Implementation of Full-Scale Feasibility Study: Financial viability of provision of small hydropower station at Diversion Chute is xxx%. Full-scale feasibility study shall be implemented based on more detailed investigation for dam operation, design and financial scheme.

② Immediate Installation of Telemetric Irrigation Management System: Telemetric irrigation management system is recommended to be installed at the same time of implementation of the spillway improvement of the Malinao Dam. It will improve water use operation for irrigation and proposed hydropower generation.

③ Monitoring of Reservoir Sedimentation and Implementation of Countermeasures for Sedimentation Countermeasures for reservoir sedimentation in Malinao Dam shall be implemented. So far no detailed reservoir sediment survey has been conducted. It is recommended to conduct periodical reservoir sedimentation survey. Some possible measures are i) construction of sediment flushing gate to sustain the active storage, and ii) removal of sediment depositions surrounding area of intake to protect from clogging of the intake. It is recommended to conduct the study for adaptation of the Japanese advance technologies such as construction methods, operation and maintenance monitoring system and sediment survey to extend reservoir life and to reduce operation and maintenance cost. Nippon Koei Co., Ltd. 9 The Study for Restoration and Upgrading Dams Under Operation in the Philippines

Draft Final Report Outline of the Targeting Country and Sector Main Report Chapter 1

CHAPTER 1 OUTLINE OF THE TARGETING COUNTRY AND SECTOR

1.1 Financial and Economic Conditions of the Philippines

The trend of main economic indicators in the Philippines are presented in this section. In the recent 5 years, the national economy has been handled stably. The national GDP in current price increased from PHP 271.8 billion in 2013 to PHP 313.6 billion in 2017, the annual growth rate varies from 5.4% to 9.5% during the same period. In terms of per capita GDP, the annual growth rates varies from 5.4% to 7.1% which shows the sound economic condition in the country.

Furthermore, unemployment rate improved from 7.1% to 5.7%, and the inflation rate were retained relatively stable from 1.4% to 4.1%. During the same period, external debt amount decreased from USD 78.5 billion in 2013 to USD 73.1 billion, the debt rate out of total GDP decreased significantly from 28.9% to 23.3% influenced by continuous economic growth.

Regarding the political aspect, new president Duterte started his government in July, 2016 after the regime of the president Aquino which started from 2010. The current president is often criticized by western countries because of his strong anti-drug campaign. However, the political administration has maintained stability because of the high approval rating of the nationals.

Table 1.1 Main Economic Indicators in the Philippines

Year Unit 2013 2014 2015 2016 2017 GDP (current price) Billion USD 271.8 284.6 292.8 304.9 313.6 Growth Rate of GDP % 9.3% 9.5% 5.4% 8.7% 9.2% Per Capita GDP USD 6,560 6,975 7,353 7,815 8,360 Growth Rate of Per Capita % 7.1% 6.3% 5.4% 6.3% 7.0% GDP Population million 98.2 99.9 101.6 103.2 104.9 Growth Rate of Population % 1.7% 1.7% 1.7% 1.7% 1.6% Unemployment Rate % 7.1% 6.8% 6.3% 5.4% 5.7% Inflation Rate % 3.0% 4.1% 1.4% 1.8% 3.2% External Debt Billion USD 78.5 77.7 77.5 74.8 73.1 External Debt out of GDP % 28.9% 27.3% 26.5% 24.5% 23.3% Source : Philippines Statistics Authority (PSA)

1.2 Outline of the Target Sector of the Project

1.2.1 Japan's Strategy for Exporting Infrastructure Systems, and Strategies for Expanding Overseas Business in Individual Sectors

General

According to "Strategic Transport Infrastructure Needs to 2030" issued by the Organization for Economic Cooperation and Development (OECD), the world's demand for infrastructures in 2030 is expected to be as much as 53 trillion dollars. Urbanization and economic growth are advancing rapidly

Nippon Koei Co., Ltd. 1-1 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Outline of the Targeting Country and Sector Main Report Chapter 1 especially in newly developing countries, and further increase in demand for infrastructures is expected in the future.

However, international expansion of infrastructure export is subject to a fiercely competitive environment, and with respect to winning orders for infrastructure, the performance of Japanese companies is significantly poorer than those of Western, Chinese, and South Korean enterprises. Although their equipment and technologies are highly regarded, Japanese companies face various issues. For example, when responding to the needs of countries and companies, they are outperformed in pricing and capabilities, they suffer from insufficiencies in brand power, management expertise, and have not established a framework for winning orders that cover project operation, maintenance, and management, having only limited human resources that are capable of supporting overseas expansion of infrastructures.

Given these circumstances, Japan has adopted a strategy for exporting infrastructure development as a whole system, which covers infrastructure design, construction, operation, and management. In May 2017, the Japanese Government announced the "Infrastructure System Export Strategy (FY2017 Revised Version)," which sets the goal of winning orders for infrastructure systems amounting to approximately 30 trillion yen in 2020.

To respond to increasing demand for infrastructure in the future, infrastructure investment which focusses not only on quantitative but also on qualitative aspects needs to be made. In May 2016, the "Initiative for Promoting Export of Quality Infrastructure" was announced at the Ise-Shima Summit. It presents one possible direction that the basic elements of quality infrastructure should take with respect to: economic efficiency, having in view not only the initial investment cost but also the lifecycle cost; safety and resilience against natural disasters; functions taking into consideration the environment and society; and contribution to the local society and economy (technology transfer and human resource development). It is a strategic policy on the overseas expansion of infrastructure system business based on Japan's advantages.

Energy Sector

Electric power demand is very high in various regions, located mainly in Asia, and is expected to increase chiefly in the fields of renewable energy and gas-fired power generation. However, competition between Japan and other countries is becoming increasingly fierce; 1) In the power generation business, newly established IPP companies, etc., have emerged in addition to enterprises in Europe, China, and South Korea. As a result, price competition in the field of renewable energy is becoming increasingly fierce, and the standards and requirements demanded by client countries increasingly strict. 2) With regards to equipment export, and in addition to the presence of Western enterprises, Chinese, South Korean, and other companies are also catching up technically. Technological and financial competitions have increased intensely. In hydroelectric power generation, Japan has the largest market share in specific technical areas but is facing rapid catch-up by Western companies.

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Under these circumstances, and giving consideration to future market potential and Japan's superiority and competitiveness, the initiative indicates a direction and provides targets for the public and private sectors regarding 1) the power generation business, 2) export of main equipment for gas-fired, coal- fired, and geothermal power generation, and 3) power transmission and distribution. Hence, the initiative maps out a direction that Japan should take, and states policies for increased winning of overseas orders.

Existing Dam Upgrading

In the field of dam upgrading, Japan has accumulated many examples of effective dam utilization. Japan has various advanced technologies in restoration and upgrading of existing dams, for example, i) to produce new effects of the dam by improving the dam operation which enable to utilize a part of active storage for the flood control, ii) to increase water storage capacity by raising dam body, and iii) to get quick economic effect by cutting down the construction period. Meanwhile, some new technologies that can support the effective utilization of existing dams are being developed such as i) installation of high- performance radar rain gauge to realize intensive operation based on observation of rainfall distribution in the catchment area in real time, and ii) construction methodology for drilling the dam body with large diameter under deep water.

Irrigation and Agriculture

The Government of Japan lists three priority areas of support in the "Country Assistance Policy for the Republic of the Philippines, April 2012". One of them is "Overcoming Vulnerability and Stabilizing Bases for Human Life and Production Activity", in which the enhancement of agricultural production and productivity as well as the improvement of the processing and distribution of agricultural products is fully supported by the Japanese government.

Generally, it can be stated that the irrigation productivity of existing irrigation schemes with large-scale dams in the Philippines is low, and it is indispensable to improve productivity through effective use of water resources. It could therefore be expected that Japan's technology for modernization of dam water resources management and dam infrastructure development or improvement such as sediment removal technology would be supported by the Philippine government.

1.2.2 Related Policies in the Philippines

Energy development policies in the Philippines

Table 1.2 shows electrification rates in the Philippines. The electrification rate across the whole country is 90%. In the area, however, the rate is 72.4%, indicating that construction of infrastructure in this area is lagging behind that of the country as a whole. In addition, taken across the country, the electrification rate in off-grid areas is lower than 50%, which represents an issue for power development.

Table 1.3 shows changes in installed capacity in the Philippines. It indicates that renewable energy accounts for 33.7% of the total energy in 2015. Hydroelectric power generation accounts for 19.2% of

Nippon Koei Co., Ltd. 1-3 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Outline of the Targeting Country and Sector Main Report Chapter 1 total energy, but installed capacity for hydroelectric generation increased by only 200 MW from 2010 to 2015.

Table 1.2 Electrification rates in the Philippines

Item Whole country Visayas Mindanao Households without access to 2,361,096 714,823 308,918 1,337,534 electricity*1 (10.4%) (5.2%) (7.6%) (27.6%) Electrification*1 89.6% 94.8% 92.4% 72.4% Households without access to 781,770 397,407 38,994 345,369 electricity in off-grid areas*2 (50.6%) (39.7%) (31.7%) (82.2%) Electrification in off-grid areas*2 49.4% 60.3% 68.3% 17.8% Note) *1: Data in July 2016; *2: Data in August 2015; Value in parentheses: Ratio to the number of households in the relevant area

Source: *1:2016 Philippine power statistics (DOE) (https://www.doe.gov.ph/philippine-power-statistics) *2:2016-2020 Missionary Electrification Development Plan (DOE)

Table 1.3 Changes in installed capacity in the Philippines (2010 to 2015)

Generated electricity Increase between Sector 2010 2015 2010 and 2015 (MW) (%) (MW) (%) (MW) Thermal power 10,921 66.8 12,435 66.3 1,514 Coal-fired 4,867 29.8 5,963 31.8 1,096 Oil-fired 3,193 19.5 3,610 19.2 417 Natural gas-fired 2,861 17.5 2,862 15.3 1 Renewable energy 5,438 33.2 6,330 33.7 892 Hydroelectric 3,400 20.8 3,600 19.2 200 Geothermal 1,966 12.0 1,917 10.2 -49 Wind, photovoltaic, and biomass 73 0.4 812 4.3 739 Total 16,359 100.0 18,765 100.0 2,406 Source: 2016 Philippine power statistics (DOE) (https://www.doe.gov.ph/philippine-power-statistics) Table 1.4 shows targets for renewable energy development in the Philippines. According to the energy plan announced by the Philippines Department of Energy, the country is positively investigating the use of renewable energy and is planning development that will allow renewable energy to generate a total of 9,685 MW of electric power by 2030. Within this plan, hydroelectric power generation is regarded as an important power source, accounting for approximately 56% (5,394/9,685) of the power produced.

Although the target total amount of power for the period 2010 to 2015 was 2,155 MW, the amount actually achieved was only 892 MW (41%). For hydroelectric power generation, the target amount was 341.3 MW, but only 200 MW (59%) was achieved. Further acceleration of power development is evidently necessary.

Table 1.4 Targets in renewable energy development in the Philippines (2011 to 2030)

(Unit: MW) Completed Development target Sector development 2010-2015 By 2015 By 2020 By 2030 Total Hydroelectric 200 341.3 3,161.0 1,891.8 5,394.1

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Geothermal -49 220.0 1,100.0 175.0 1,495.0 Wind 1,048.0 855.0 442.0 2,345.0 Photovoltaic 739 269.0 5.0 10.0 284.0 Biomass 276.7 - - 276.7 Marine - - 35.5 35.0 70.5 Total 892 2,155.0 5,165.5 2,553.8 9,685.3 Source: Values for completed development: 2016 Philippine power statistics (DOE)( https://www.doe.gov.ph/philippine- power-statistics) Values for development targets: DOE “III Renewable Energy Plans and Programs (2011-2030)”

1) Change in electricity supply framework in the Philippines

Electricity supply in the Philippines was prone to chronic power shortages. To eliminate this problem, a 1987 Presidential decree was issued allowing private companies to enter the power generation business, which had hitherto been a monopoly of NPC. Following this, the “Basic Act on Entry of Private Companies into Infrastructure Construction” was established in 1990 and then revised in 1994. In 2001, the “Electric Power Industry Reform Act” (EPIRA) was established with the aim of promoting an effective competitive electricity market. Table 1.5 shows changes in the electricity supply framework.

Hydroelectric dams in the Philippines were previously under the management of NPC, but the “Power Sector Assets and Liabilities Management Corporation” (PSALM) was founded in order to promote the entry of private companies.

Table 1.5 Changes in electricity supply framework in the Philippines

Electricity supply Past Present IPP (asset management by PSALM and Power generation NPC, IPP coordination by IPPA), privatized NPC power plants NPC

Power transmission NPC Private companies

Power distribution Wholesaling: WESM, IPPA Power distribution companies and electric Retailing: Power distribution companies, private utility association dealers, and electric utility association

Source: The Study Team ＊IPP: Independent Power Producer, PSALM: Power Sector Assets and Liability Management Co., WESM: Wholesale Electricity Spot Market, IPPA: IPP administrator The operation and management of hydroelectric power plants has been transferred from NPC/PSALM to Independent Power Producer (IPP) by “Build – Operate – Transfer” (BOT) or “Build – Rehabilitate – Operate – Transfer” (BROT) contracts in order to allow private companies to enter the business. However, even though the management of power generation facilities has been transferred from PSALM to IPP Administrator (IPPA), the wholesale and

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purchase of electricity is under the supervision of an organization called the Energy Regulatory Commission (ERC).

The subject of this survey is IPPA (an on-grid private company) and the off-grid facilities under the control of NPC.

Given the above circumstances, the electricity business sector of the Philippines faces the following issues.

i. Provincial areas, even in Luzon Island, are not provided with a 24-hour electricity supply. ii. In Mindanao, the electricity supply rate is only 70%, and approximately 18% in off- grid areas. These are low values compared to those in other areas of the country, and indicate issues relating to expanding the availability of electricity in all areas. iii. Electricity charges are high. iv. At present, coal-fired power generation accounts for half of total installed capacity. To achieve the CO2 reduction required by the Framework Convention on Climate Change (COP), it is necessary to increase the proportion of renewable energy. v. Gas-fired power generation using gas supplied from the Malampaya gas field accounts for 40% of the electricity consumption of Luzon Island. However, it is expected that this gas field will become exhausted in 2024. vi. The Philippines is a multi-island country, but interconnected transmission lines can be used to connect the islands. However, power transmission and distribution have been separately privatized, and the construction of transmission line networks is not mandatory. As a result, privatization has not led to new investment. The Philippines often suffers disasters, and needs electric power facilities that are strongly resilient to their effects. However, all sectors related to electric power have been privatized, and there are issues regarding governance by the authorities.

Greenhouse Gas (GHG) reduction measures in Philippines

In implementing the "Intended Nationally Determined Contributions” (INDC）policy formulated by each ASEAN country, the Philippine government targets to reduce 70% GHG emissions by “Business As Usual” (BAU) ratio by 2030. (With the condition that international cooperation could be obtained)

Meanwhile, the Philippine CO2 emission from energy generation accounts for about 50% of the county’s total CO2 emissions (2010). For this reason, reduction of CO2 emissions from energy generation would be very important in reducing GHG emissions. Using hydropower facility as a source of renewable energy would contribute much to CO2 reduction.

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Infrastructure improvement for water resources in the Philippines

The main government agency for infrastructure improvement in the Philippines is the Department of Public Works and Highways (DPWH). Currently, the agency has continuously initiated the improvement of water infrastructures as stipulated in the ‘Philippine Medium-Term Development Plan’ (2017-2022) in order to mitigate flood risks. It includes (1) renewal and formulation of flood management plans and wastewater management plans for the 18 major river basins of important watersheds, (2) improvement of coordination capacity of river management, (3) updating the design and maintenance standards for flood control facilities, (4) establishment of river information database, etc. In “The Philippine Strategy on Climate Change Adaptation” (2010-2022), it is stated that risks and vulnerabilities can be reduced by appropriate infrastructure development.

Currently, DPWH does not manage dam directly, but it is the administrative agency tasked with the implementation of river flood control measures. It is presently considering plans to construct dams in major like and River. Dam renewable projects are expected to lead to improvement of flood risk management of downstream of the rivers.

Irrigation system improvement development in the Philippines

The successive regimes of the Philippine government put a priority on improvement of agricultural productivity and improvement of livelihoods of farmers (alleviation of poverty) in the national development plan. The government is promoting agricultural rural development for effective utilization of land and water resources and development of irrigation facilities as the minimum requirements.

The current situation related to irrigation development and strategies for irrigation development is described in the Philippine Development Plan (2017-2022) which is a part of 10-year Irrigation Development Master Plan (2017 - 2026). The problems being encountered in irrigation development are intensified conflict over irrigation water, regional disparity in the available amount of water resources and rainfall, less improvement of irrigation water utilization rate and increased demand for key foods. Accordingly, implementation strategies should include irrigation facility design that can cope with climate change, promotion and support of public and private partnership projects (PPP) for irrigation organization and hydropower development.

1.2.3 Needs of Recipient Country

Before 1987, the hydropower generation dams in the Philippines were operated by NPC alone. After that, they were allowed to be operated by private companies. In 2001, the Electric Power Industry Reform Act (EPIRA) that aims to introduce a rational competition on the electricity market was enacted. By this act, the Power Sector Assets and Liabilities Management Corporation (PSALM) was established to implement the sales of the NPC assets. However, as of June 2016, there are still eight (8) hydropower generation dams which had been left from the privatization. Seven dams are located in Mindanao; six (6) are cascade type dams in and one (1) dam in Pulangui River. The reasons are, they were identified as non-sale assets at the time of the enactment of the EPIRA, and also, they were already

Nippon Koei Co., Ltd. 1-7 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Outline of the Targeting Country and Sector Main Report Chapter 1 suffering from aging and reservoir sedimentation since they had been constructed in as early as the 1970’s and 1980’s. The table below shows the list of 16 hydropower generation dams in Philippines.

Table 1.6 Present Conditions of Hydropower Generation Dams Operation in Philippines

Name of Install IPPA Type of Hydropower Capacity Operator Owner (IPP Administrator) Contract Station （MW） San Roque Power Strategic Power Development Non- San Roque 435.0 BOT-PPA Corporation Corporation NPC/IPP Kalayaan PSPP 739.2 CBK Power Company Ltd. PSALM Corporation NPC/IPP BROT-PPA Non- Magat 380.0 SN Aboitiz Power, Inc. SN Aboitiz Power, Inc. NPC/IPP Caliraya 35.0 CBK Power Company Ltd. PSALM Corporation NPC/IPP BROT-PPA Angat M 200.0 Angat Hydro Power Angat Hydro Power Non- Angat A 46.0 Corporation Corporation NPC/IPP Pantabangan- First Gen Hydro Power Non- 132.0 First Gen Hydro Power Corp. Masiway Corp. NPC/IPP SN Aboitiz Power Hydro, SN Aboitiz Power-, Non- Ambuklao 105.0 Inc. Inc. NPC/IPP SN Aboitiz Power Hydro, SN Aboitiz Power-Benguet, Non- Binga 140.0 Inc. Inc. NPC/IPP CE Casecnan Water & Casecnan(NIA) 165.0 PSALM Corporation NPC/IPP BOT-PPA Energy Co., Inc. Agus 1 80.0 NPC -Mindanao Generation PSALM Corporation NPC Agus 2 180.0 NPC -Mindanao Generation PSALM Corporation NPC Agus 4 158.1 NPC -Mindanao Generation PSALM Corporation NPC Agus 5 55.0 NPC -Mindanao Generation PSALM Corporation NPC Agus 6 219.0 NPC -Mindanao Generation PSALM Corporation NPC Agus 7 54.0 NPC -Mindanao Generation PSALM Corporation NPC Source: DOE List of Existing Power Plant For the irrigation dams managed by NIA, rehabilitation works of 127 existing national irrigation facilities were conducted to increase operation rate and to strengthen the organization for operation and maintenance under the OECF Loan in 1987. However, since 30 years have passed, the facilities need to be improved for securing long life and seismic resistance, increasing efficiency and upgrading functions.

Most of the NIA irrigation dams are not equipped with hydropower generation facilities. Even if only small-scale hydropower generating facilities are installed in these dams, these would contributes to rural electrification and development of renewable energy, which were originally the responsibility of NPC. The possibilities for applying these schemes are studied.

1.2.4 Analysis of the Advantages and Disadvantages of Rival Country Companies and Japanese Companies in Related Sectors

From the viewpoint of dam upgrading and rehabilitation, Japanese companies have the following advantages and disadvantages.

Advantages

 In the survey and design stages, they can perform planning and design based on accumulated

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experience of domestic construction which could be carried out whilst operating the water reservoir.  From the above, since construction is performed whilst operating the water reservoir, there is only a small impact on the electricity supply or supply of irrigation water.  Since maintenance-free facilities can be used, the costs required for long term maintenance and management can be reduced.  Dam operation can be optimized by using XRAIN or another high performance radar precipitation information system.

Disadvantages

 Initial investment costs are high.  In the event of a failure, the cost of replacing some equipment and materials is high. If no sales agent is available, time may be required to procure replacements.  Optimum operation of the dam requires a sufficient level of ability (support from a Japanese company is necessary, but support fees are high). In the field of dam upgrading and rehabilitation, Japan possesses leading edge technologies, such as: 1) increasing dam reservoir capacity by raising the height of the existing dam; 2) additional construction of discharge facilities; 3) prevention of sediment.

Measures to prevent sediment include construction of sand elimination bypass tunnels and construction of intake gates when modifying water intakes. The alloy-saving duplex stainless steel used for modification of gates, and water intake facilities, etc., is not only strong but also highly effective in relation to maintenance. This is a new original technology developed in Japan and unequalled throughout the world.

Modulus of elasticity: 200 GPa 2 Alloy-Saving Duplex 400 N/mm Alloy-Saving Duplex Stainless Steel Stainless Steel

2 SUS304 205 N/mm Twice the Strength Save cost drastically by using thinner and lighter material

Stress

Conventional Alloy-Saving Duplex stainless steel stainless steel Strain Source: The Study Team

Figure 1.1 Characteristics of Alloy-saving duplex stainless steel (high strength and lightness)

Nippon Koei Co., Ltd. 1-9 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Outline of the Targeting Country and Sector Main Report Chapter 1

When construction is performed to raise an existing dam, the distribution in capacity between flood control and water for utilization may be revised to make it more efficient, in consideration of the increase in reservoir capacity. In this case, dam raising may be accompanied by provision of additional spillway gates, which would require advanced construction techniques, and further construction works, such as the modification of water intakes.

When dam upgrade construction can be performed with water remaining in the dam reservoir, the period during which power generation is suspended can be minimized. Japan's leading edge technologies could allow this to be achieved. In this case, although construction costs increase, the loss due to suspension of power generation during the construction period can be minimized. This is in contrast to construction being performed with the water drained out from the dam and the power generation being completely stopped. Hence, in this regard, Japan's technologies could be considered economically advantageous. In addition, the climate of the Philippines has clearly divided rainy and dry seasons. If construction which is performed during the dry season is accompanied by suspension of the dam's water supply, then agricultural production on its downstream side will be severely affected. Permission, therefore, may not be granted for such construction.

When we consider the maintenance of running water supplied through downstream discharge from the dam, and the future maintenance and management of dam gate facilities, we may conclude that Japan's technologies possess significant advantages over those provided by other countries.

1.3 Present Condition of the Study Area

1.3.1 Existing Dams in the Philippines

There are 58 existing dams (H>15 m) in Philippines. Location map, List of the Dams and Photos are presented in Appendixes 1 to 3, respectively.

1.3.2 Present Conditions of the Pre-Feasibility Study Area

Geographical Location

The island Province of Bohol is located in the central part of the Philippine Archipelago with bearings of north latitude 9⁰ 30’ and 10⁰ 15’ and east longitude 123⁰ degrees and 40’ (Figure 1.2). It is surrounded by the island of Cebu at the northwest, Leyte at the northeast and Mindanao at the south. Bohol is about 1 hour and 45 minutes directly south of Manila, the capital of the Philippines, and 30 minutes southeast of Mactan Island, Cebu. It has 654 kilometers of coastline and 6,245 square kilometers of municipal waters covering the major islands and islets. The province is accessible both by air and sea transportation.

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Source: https://lga.gov.ph/province/info/bohol

Figure 1.2 Geographical Location Map of Bohol and Two Project Sites

Topography

Bohol’s terrain is variable from nearly flat to low rolling, moderate to very steep slopes with 5 to 50 meters high cliffs in the Sierra-Bullones limestone formation. The more rugged terrain is found in the southern part of the province although the Ubay volcanic rocks and Boctol serpentinite in the north and northeast are of moderate and rugged slopes in most of their outcrop areas. The central valley is almost rolling to moderately steep.

There are several mountain ranges found in Bohol. Two sets of them are found in the northeastern side of the mainland and located between the municipalities of Alicia and Ubay that generally trend to the north and south directions with a maximum elevation of about 404 meters above sea level. The northern end of the these mountain ranges is drained by the Lomangog River while the southern part by the east flowing San Pascual River which empties into the Cogtong Bay. Farther east are two other mountain ranges, the Mt. Tanawan and Mt. Candungao with 460 and 500 meters elevation, respectively. Both are prominent landmarks rising as they do several meters above the surrounding landscape.

From Mt. Tanawan going southwestward, it declines gradually in height until it finally joins southwestwardly the foothills of Calape. The main range of hills extending from Calape joins to the southwestwardly trending mountain range from the interior, runs south and out to Loon Peninsula terminating in Punta Cruz, .

The Range follows roughly the trend of the south coast. The highest point of this range in the entire province is Mt. Mayana in Jagna with a height of 827 meters above sea level.

Slope

The province has six slope ranges from level to very steep. Level to nearly level areas is mainly located along the coast and the islands. The steep slopes are prevalent in the mountainous area, covered mainly

Nippon Koei Co., Ltd. 1-11 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Outline of the Targeting Country and Sector Main Report Chapter 1 by carbonate rocks (Wahig Limestone), Volcanic extrusive and Magmatic Rocks (Ubay Volcanics and Jagna Andesite: (BSWM, DA Region 7)

Geology/Soil

The Island Province of Bohol is predominantly a sedimentary island. It developed from the magmatic, tectonic mechanism that resulted from the under thrusting of the southwest Philippine Plate east of Samar and Surigao. Ongoing erosion, transport and sedimentation continue to accumulate marine and terrestrial deposits in the Bohol basin.

Bohol is composed of 12 rock formations that exhibit different landforms. The oldest rock formation belongs to the Basement Complex particularly found at the eastern flank of the island. Because of the sub-crustal movements like faulting, seven different geomorphologic landforms were produced, namely the Anda Peninsula, Loon Peninsula, Northwestern Area, Central-Northern Sedimentary Area, Eastern Volcanic, Limestone-Haycock Hills and Central Volcanic.

The major part of the island of Bohol occupies the southeastern portion of the Visayas sea basin. The basement rocks underlying Bohol are composed of metamorphic and ultramatic rocks. These types of rocks are found in the eastern part of the province, which roughly defines a north-northeast alignment. In the southwest is an ophiolite-metamorphic belt with a similar trend that extends from Zamboanga to Sulu Islands. The pre-tertiary diorite plutons in Bohol are believed to be representatives of a southeast facing arc system related to inactive northeast trending trence, a segment of which is defined by the associated ultramatic-metamorphic rock assemblages in the province.

Soil

According to the Bureau of Soils and Water Management (BSWM Region 7, Cebu) there are 22 different types of soil that can be found in Bohol, which differ mainly in physical, chemical and morphological characteristics. The soil depth is relatively thin ranging from a minimum depth of 24 centimeters to a maximum of 30 centimeters and its fertility is good throughout the province. Most of the hills and ridges have meager to no soil cover due to fairly rapid surface drainage over most of the province land. Clay soils with fine textures are predominant throughout the island province. The dominant soil type is Ubay Clay, which occupies in the northeastern part of Bohol constituting 19.53 percent or 79,644 hectares of the total land area of Bohol. The soil derived from all rock types are generally clay and silty with sandy soil limited in some parts of the coastal area. Soils on steep to very steep side slopes (18-50%) are clay loam to clay.

Soil Erosion

Soil erosion in Bohol frequently occurs in areas that have been farmed or at construction sites. Most of the accelerated removal of soil is man-made. According to the Bureau of Soils and Water Management Report, more than 66% of the soils in province are affected by erosion of different degrees (slightly, moderate and severe) and less than 31% of the island show no apparent erosion.

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FAO (2000) estimated that 79% of Philippine lands are threatened by severe degradation, using the Global Assessment of Soil Degradation database. 1

Removal of the natural vegetation cover due to practices such as deforestation, overgrazing or industrial farming practices (e.g., tillage) leaves the soil exposed to the action of climatic factors, such as rain and wind (MEA 2005). The mobilization and deposition of soil can significantly alter the nutrient and carbon cycling (Quinton et al. 2010), as eroded soil may lose 75–80 % of its carbon content, with consequent release of carbon to the atmosphere (Morgan 2005, BSWM Region 7 and Philippine Land and Soil Management Atlas for ; Bureau of Soils and Water Management, Department of Agriculture, Region 7, Cebu City).

Climate/Temperature

The climate in Bohol is characterized by two distinct seasons. The dry season occurs from late January to May, while the wet season is from June to December. The weather varies in different areas—warm and dry along the coast; cold and humid in the interior. The average rainfall is about 2000.0 mm which is evenly distributed in the island. The watershed is also one of the most important sources of water for agriculture and domestic use (ACIAR Report 2001).

The climate is typically equatorial – temperature range over the year is less than 3⁰C and/or 5.4⁰F, and annual rainfall exceeds 1,500 millimeters and/or 59 inches. The dry season starts in February and lasts through April sometimes extending to mid-May. The climate in Ubay falls within Coronas climate type IV, characterized by not very pronounced maximum rainfall with a short dry season from one to three months and a wet season of nine to ten months.

Ubay has a tropical climate. Most months of the year are marked by significant precipitation, making agriculture favorable it supports at least two rice crops per year. The short dry season has little impact. Ubay is classified as Am (Tropical monsoon climate) by Köppen–Geiger climate classification system.

Source: http://jeepneyguide.com/bohol/climate

Figure 1.3 Average Temperature and Precipitation in Bohol

1 Department of Environment and Natural Resources (DENR) Bohol and Banilad,Cebu, Region 7, Technical Report 2, Geology, Soil and Land Resources Appraisal and Training Proje1ct (Philippines), Bureau of Soils and Water Management (BSWM). Nippon Koei Co., Ltd. 1-13 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Outline of the Targeting Country and Sector Main Report Chapter 1

Adaptation to Climate Change

The Philippine climate is influenced by large-scale atmospheric phenomena that bring in substantial amounts of rains almost all year round. However, due to the uneven distribution of rain with respect to time and space and the occurrences of extreme events such as floods and droughts, the country’s water resources have in the past experienced imbalances. Global warming is expected to occur due to increased carbon dioxide concentration in the atmosphere. Global surface temperature will increase by at least 2.0°C by the next century. Significant changes in the earth’s climatic system, particularly an alteration of rainfall and temperature in both time and space, is expected. During the past few decades, extreme climatic events have adversely affected the Philippine economy.

The IPCC estimated the change of global temperature based on the Fourth Special Report on Emission Scenarios (SRES), which describes several scenarios on the future global emission volume of greenhouse gas (such as carbon dioxide and nitrogen monoxide and methane gas) and sulphate. The IPCC estimated based on the SRES that the present global average temperature would most likely rise by 1.8 to 4.0°C at the end of the 21st Century. Significant changes in the earth’s climatic system, particularly an alteration of rainfall and temperature in both time and space, are expected.

Predictions from GCMs (general circulation models) based on doubled CO2 emissions were used in this study as the basis for climate change scenarios. The National Center for Atmospheric Research (NCAR), through the US Country Studies Program, has provided results from several GCMs that have simulated the effect of CO2 doubling on temperature, rainfall, and other meteorological parameters. Three models were chosen to represent future values of rainfall and precipitation under a double CO2 scenario. The three (3) models selected were the Canadian Climate Center Model (CCCM), the United Kingdom Meteorological Office (UKMO) model, and the Geophysical Fluid Dynamics Laboratory (GFDL) model.

Assessment of climate variability and change impacts on the performance of a flood protection system is manifested by the following: (a) climate change scenarios; (b) hydrologic processes; and (c) impacts to the development of flood control measures (structural and non-structural).

Other Natural Hazards in Bohol

A comprehensive Geo-hazard Assessment per municipality in Bohol was conducted by Provincial Government of Bohol the Mines and Geo-Sciences Bureau of DENR Region 7 in September 2007. each was rated with low, moderate or highly susceptible to landslide and/or flooding There are other risks & potential disasters to be addressed: landslides, tsunamis, tropical cyclones, earthquake, and among other. Majority of the coastal zones in the Province of Bohol is highly susceptible to liquefaction; storm surges and tsunami.

Minor and major fault lines are evident on the island as shown by terraced encarpments occur ring in its southern and central parts. The terraced escarpments in the Ilihan Steep escarpments notably in Loon, Tagbilaran and in Anda Peninsula further prove vertical upliftment caused by tectonics. Earthquakes

Nippon Koei Co., Ltd. 1-14 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Outline of the Targeting Country and Sector Main Report Chapter 1 have been felt in Bohol but only an average of one perceptible shock is reported each year and Figure 1.4 a map illustrating the active fault lines in Bohol.

Source: Philippine Institute of Volcanology and Seismology

Figure 1.4 Active Fault Lines in Bohol

Nippon Koei Co., Ltd. 1-15 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Methodology of the Study Main Report Chapter 2

CHAPTER 2 METHODOLOGY OF THE STUDY

2.1 Outline of the Study

Title of the Study Study for Restoration and Upgrading Dams Under Operation in the Republic of the Philippines

Contract Period July 19, 2018 - February 28, 2019

Purpose To study present conditions of existing dams in Philippines, to select urgent and priority projects for dam improvement and upgrading, and to conduct pre-feasibility study

Scope of Works Study for Present Condition of Existing Dams

Proposal of improvement plan adopting the Japanese Technology for the existing hydropower generation dedicated dams and existing multipurpose dams which need to be rehabilitated.

Proposal for hydropower development as a renewable energy source contributing to the increase of local domestic power supply targeting the existing irrigation dams mana (H>15m).ged by NIA.

Study Area, Facilities Existing Dams in Philippines Location Map, List of Objective Facilities and Photos are shown in the Appendixes 1, 2 and 3, respectively.

Counter Part NIA/NPC

Report Final Report

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2.2 Methodology and Organization of the Study

2.2.1 Work Flow of the Study

Work flow of the Study is shown below:

Study for Restoration and Upgrading Existing Dams Under Operation in the Philippines

1. Project Selection Study

1.1 Collection of Basic Data and Information Evaluation Criteria 1 1.2 1st Screening of Candidate Projects

1.3 Data collection for Candidate Projects

1.4 2nd Screening of the Shot-listed Projects and Evaluation Selection of Priority Project Criteria 2

2. Pre-Feasibility Study

2.1 Basic Design

2.2 Determination of Project Scale, Estimation of O&M Cost

2.3 Project Implementation Organization, Implementation Schedule

2.4 Study and Proposal of Financial Arrangement

3. Study for Application of Japanese Advanced Technology

3.1 Study for Utilization of Policy Support Scheme, etc.

3.2 Confirmation of Superiority of Japanese Companies, Prediction of Benefits to Japan (Economical Effect)

3.3 Study to Enrich the Project Proposal

3.4 Study for Promotion of Possibility and Development for Horizontal Expansion to Other Countries 3.5 Study to Strengthen the Cost Competitiveness for Project Participation of Japanese Companies

4. Presentation of the Study

5. Preparation of Final Report

Source: The Study Team

Figure 2.1 Work Flow of the Study

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2.2.2 Organization of the Study Team

(Main Company） Project Team Nippon Koei Co., Ltd. A1. Team Leader A5. Project implementation (NK) Business Plan / dam renewable technology plan assistance International Consulting Operations Fukuda Tadahiro （NK） Hijikata Motoyuki （NK） Water Resources & Energy Dept. [InfrastructureG] [Business planning and evaluation G ] (Cooperative company ） A2. Irrigation Engineer Matsuura Natsuno（NK） Nippon Steel & Sumitomo Metal A4. Economic/ Financial Corporation A3. Hydro-Mechanical Analysist (NSSMC) Engineer Murakami Takashi (KRC) Machino Shunsuke(NSSMC) B3.Social and Environmental B1. Dam Engineer Specialist Olivia Dumaya (PKII) Eleanor A. Pintor (PKII) outsourcing contract B2. Irrigation Engineer (1) Koei Research & Consulting Inc. Alexander Reuyan (PKII) A4. Economic/ Financial Analysist Survey and design assistance B4. Cost Engineer B5.CAD/GIS (2) Nippon Steel & Sumitomo Metal Rizalina Danguilan (PKII) Corporation TBN (PKII) A3. Hydro-Mechanical Engineer

（3) Philkoei International, Inc. B1 . Dam Engineer B2. Irrigation Engineer ◎ Existing Dam dam renewable technology adviser B3. Social and Environmental Specialist Nippon Koei Co., Ltd. Domestic Consulting Operations B4. Cost Engineer Dam & Power Generation Dept. B5. CAD/GIS

Source: The Study Team

Figure 2.2 Organization Chart of the Study Team

2.3 Implementation Schedule of the Study

2.3.1 Work Schedule of the Study

2018 2019 Remarks No Item A M Ｊ J A S O N D J F M 1 2 3 4 5 6 7 8 9

1 Project Selection Study

1.1 Collection of Basic Data and Information

1.2 1st Screening of Candidate Projects

1.3 Data collection for Candidate Projects

2nd Screening of the Shot-listed Projects and Selection of Priority 1.4 Project

2 Pre-Feasibility Study

2.1 Basic Design 2.2 Determination of Project Scale, Estimation of O&M Cost 2.3 Project Implementation Organization, Implementation Schedule 2.4 Study and Proposal of Financial Arrangement

3 Study for Application of Japanese Technology

3.1 Study for Utilization of Policy Support Scheme, etc. Confirmation of Superiority of Japanese Companies, Prediction of 3.2 Benefits to Japan (Economical Effect) 3.3 Study to Enrich the Project Proposal Study for Promotion of Possibility and Development for Horizontal 3.4 Expansion to Other Countries Study to Strengthen the Cost Competitiveness for Project Participation 3.5 of Japanese Companies 4 Presentation of the Study

5 Preparation of Final Report

Meeting 1st 2nd 3rd 4th

Report IC/R IT/R DF/R F/R

Presentation

Works in Field Works in Japan

Source: The Study Team

Figure 2.3 Work Schedule of the Study Nippon Koei Co., Ltd. 2-3 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Methodology of the Study Main Report Chapter 2

2.3.2 The First Field Survey

Interview and surveys were implemented to related entities such as counterpart agencies and operating private companies of hydropower projects. The data which could not be collected in Japan were requested and collected during the site survey.

Outline of the first Filed Survey is shown below.

1) Survey period ：2018/8/7 - 16 (10 days for total)

2) Survey contents：

- Courtesy, Meeting and Interview for counterpart - Explanation of Inception Report and project plans - Explanation of the first screening and Request for submission of related information - Additional request for collection and submission of related information and Explanation of the basis of the second screening, - Scheduling of the second field survey 3) Main interviewees：

(Japan side) - Japan Embassy (ｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘ ｘｘｘｘｘｘｘｘｘｘ） - DPWH-JICA Expert (ｘｘｘｘ) - JICA Philippine office (ｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘ ｘｘｘｘｘ) (Philippine side) - NIA (Mr.Sulaik: Deputy Administrator for Engineering and Operation, other 8) - NPC (Mr.Sison, Department Mgr., DMD-PES, other 7) - San Roque Power Corporation (ｘｘｘｘ: President) - CBK (ｘｘｘｘｘ: Chief Executive Officer, other 1) - SN Aboitiz Power Group (ｘｘｘ: President, other 1)

Table 2.1 Schedule of the first field survey

Date Schedule Remarks 8/7 (Tue) 1st Arrival from Japan, Internal Meeting 8/8 (Wed) 2nd AM: JICA Expert, PM: Japan Embassy Explanation of study 8/9 (Thu) 3rd AM: Meeting with NIA Explanation of Inception report and first PM: JICA Philippine office screening, Request for submission of related information 8/10 (Fri) 4th AM: Meeting with NPC ditto PM: Data collection 8/11 (Sat) 5th Data collection Conducted around Manila 8/12 (Sun) 6th Holiday

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8/13 7th AM: San Roque Power Company Explanation of Inception report and first (Mon) PM: CBK Power Company screening, Request for submission of related information 8/14 (Tue) 8th AM: Data collection Ditto PM: SN Aboitiz 8/15 9th AM: First Survey Report Meeting with Additional request for collection and (Wed) NIA submission of related information, PM: First Survey Report Meeting with Explanation of the basis of the second NPC screening, Scheduling of the second field survey 8/16 (Thu) 10th AM：Internal Meeting, PM: Return to Japan Source: The Study Team

2.3.3 The Second Field Survey

Second field survey were conducted for the meeting with related agencies, site reconnaissance for the short-listed dams and explanation of second screening. Outline is shown below.

1) Survey period ：2018/09/26 – 2018/10/25 (30 days for total)

2) Meeting with counterparts

- Explanation of draft Interim Report (results of the first field survey, 1st screening) - Request for supports during site reconnaissance and schedule arrangement - Explanation of the evaluation criteria of the second screening 3) Site reconnaissance for the short-listed dams

- Binga/Ambuklao Dams (NPC/SNAP) - Pulangi Dam (NPC) - Magat Dam (NIA/SNAP) - Dams in Bohol (Capayas, Bayongan, Mainao Dams) (NIA) - NIA SLIP Dams (Miral, Lupao, Tangilad) (NIA)

Table 2.2 Schedule of the Second Field Survey

Week Schedule Remarks 1st Sep.26-30 Meeting with NIA Site reconnaissance (Lupao in ) 28(day trip) 2nd Oct.1-7 Meeting with NIA RO Site reconnaissance (3 dams in Bohol) 1-5 Site reconnaissance (Miral Dam(NIA)/ Pulangi Dams(NPC) in 4-5 Mindanao) 3rd Oct.8-14 Site reconnaissance (Tangilad in Bataan) 8(day trip) Site reconnaissance (Magat Dam) 9-14 4th Oct.15-22 Meeting with NPC/SNAP Site reconnaissance (Ambuklao/Binga Dams) 16-18 Site reconnaissance (3 dams in Bohol) 19-21 5th Oct.23-25 Meeting/Reporting Meeting with EOJ Source :The Study Team

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CHAPTER 3 PROJECT COMPONENTS AND TECHNICAL STUDY

3.1 Background of the Project

In the Philippines, water and energy demands have recently increased rapidly due to population increase and upswing of the economic development. For these demands, the dam reservoirs have very important roles as the facility that can control seasonal variation of river flow and water resources that can generate hydropower as a renewable energy.

The high dams in the Philippines are categorized into two; one is the multipurpose and the irrigation dams managed by the National Irrigation Administration (NIA）and another is the hydropower dedicated dams managed by the National Power Corporation (NPC). The operation and maintenance of most of the NPC dams have already been transferred to consortiums of private companies. Some Japanese companies participate in these consortiums such as the Marubeni/Kansai Electric Power (San Roque Dam) and the Sumitono Corporation/J-Power (Kaliraya Dam).

On the other hand, NIA owns five (5) high dams including the Magat Dam which is the largest dam in Philippines. The water resources of these dams have been utilized not only for irrigation water supply but also for hydropower generation and flood control, contributing to regional irrigation developments economic growth and safety and security in the area.

However, a few decades after construction of these dams, dam facilities and sedimentation of reservoirs have already posed problems to their operations, causing the obstructions of water supply and operation of hydropower generation It is predicted that the dam function will be lost completely and water supply and hydropower generation will be stopped.

For example, in the in the upper in Central Luzon, the dam operation had been stopped due to sedimentation problem and due to the damage caused by earthquake in 1999. The dam management however was transferred from NPC to the SN Aboitis Power, and rehabilitation of the intake and restoration of hydropower generating facilities had been completed by 2011.

As seen in the above, plan formulation and implementation of the study for rehabilitation and restoration of dams like that of the Ambuklao Dam are urgent issues for most of the exiting dams owned by NIA, NPC and Consortium. Comprehensive studies that would determine the reservoir sedimentation condition and soundness of the dam body and its related facilities in order to formulate the rehabilitation plan for succeeding future rehabilitation works need to be undertaken.

3.2 Basic Approach of the Study

3.2.1 Key Considerations and Issues on the Study

Key considerations of the Study are presented below:

i. Link to the strategy of infra system export and the overseas development strategy by sector of the Government of Japan

Nippon Koei Co., Ltd. 3-1 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Project Components and Technical Study Main Report Chapter 3

ii. Consideration of policy implication of the Government of Philippines and the wide range of beneficiaries etc. iii. Operation and maintenance of infrastructure for medium and long term. iv. Efforts to highlight the Japan Assistance v. Improvement of cost competitiveness vi. Formulation of project to be expected to reduce the energy source CO2. For i and ii, the relationship between the Study and Japanese energy policy and infrastructure development, and integrity with energy policy of the Philippines and beneficiaries are presented tables below:

Table 3.1 Relation between the Study and Energy Policy and Infrastructure Development of Japan

Sector Relation to the Policies of Japanese Government Energy Contribution to improvement of efficiency of renewable energy generation Infrastructure Overseas expansion for dam upgrading projects Irrigation/Agriculture Contribution to the Country Assistance Policy of the Philippines, “increase agricultural production and productivity” Source: The Study Team

Table 3.2 Integrity with Energy Policy of the Philippines and Beneficiaries

Government Policy Integrity with Energy Policy of the Philippines and Beneficiaries Energy Improvement of rural electrification rate, contribution to achieve the development goal of renewable energy. Infrastructure Reduction of flood risk and vulnerability, and climate change adaptation by conducting proper maintenance of existing infrastructures, capacity development of operation and maintenance of the infrastructure. Irrigation/Agriculture Expansion of agricultural productivity by effective use of the water resources of dams Source: The Study Team For the items of iii- vi, the Study is conducted including the following considerations:

Table 3.3 Considerations and Approaches of the Study for Application of Japanese Advanced Technology

Considerations Approach Operation and maintenance of  One of advantages for application of the Japanese Technology is to infrastructure for medium and reduce the life cycle cost;, thus it will be considered for project long term. evaluation.  Necessity of countermeasure for sedimentation in existing dams are examined, and its impact to longer life is evaluated  Application of new materials such as alloy-saving duplex stainless steel is studied to improve the function of maintenance, like maintenance free, improvement of abrasion resistance and weight saving.

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Efforts to highlight the Japan  Packaged development of dam upgrading technology is the Assistance Japanese comprehensive technology. Aside from this, Japan has advanced technologies such as 1) investigation and construction methods which can be applied during the dam operation (underwater robot, temporary closure method, etc.) 2) renewal technologies for existing facility and adjacent construction method. These can highlight the Japanese technologies.  High resolution rainfall data obtained by XRAIN can be used for flood operation of dam to control outflow discharge safely in the downstream river. Improvement of cost  One of the advantages for application of the Japanese Technology competitiveness is to reduce decreasing energy generation during construction period and cost saving of operation and maintenance in the life cycle of the project in spite of the high initial cost.  In case of applying the alloy-saving duplex stainless steel that is high quality but expensive, cost reduction for procurement and production such as fabricating at site will be studied. In addition, the weight saving of the material and thinning of the main body, improvement of construction workability will be included in the evaluation item. Point of view from formulation of  The existing dam rehabilitation / hydroelectric power plant capacity project to be expected to reduce development project is to rehabilitate and refurbish existing the energy source CO2. facilities which have reduced power generation efficiency. It contributes directly to improvement of power generation efficiency, it can be expected to reduce CO2 emissions of energy origin.  Hydropower generation is clean energy with extremely low CO2 emissions. Projects that would add new small hydropower plants to existing irrigation dams can reduce the CO2 emissions per unit of electricity, compared to the case where corresponding energy is generated by thermal power plant.  The proposed project focuses on restoration and improvement of existing facilities, and environmental load (deforestation and large scale Development) can be reduced compared with new projects that develop equivalent functions. Also it contributes to CO2 reduction.  Energy source CO2 reduction effect shall be included as one of the selection criteria at the second screening of candidate projects. Source: The Study Team

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3.2.2 Basic Approaches for the Project Components

Procedure and evaluation criterial for selection of the priority project

1) Grouping of objective dams

In the Philippines, there are several agencies related to ownership and management of the existing dams, i.e. NIA, NPC and private companies. Because the approach to formulate the countermeasure is different by function and ownership of each dam, the assistance scheme to be adapted should be selected as the suitable ones.

As shown below, the existing dams are categorized into some groups, and adapted scheme will be proposed by each group in this study.

To increase the hydropower generation capacity in Philippines, it is considered that there are several options that (A) construction of new hydropower generation plants (dam type or run-off type), (B) upgrading the existing hydropower generation plants and (C) adding hydro power generating facility onto the existing dams (for example, to install a small-scale hydropower generator onto the existing irrigation dams for dependent power generation using irrigation water.

In this study, the option (A) is excluded from the scope of the works, but the options (B) and (C) will be the target ones.

The options (B) and (C) are categorized into two groups as below;

Group 1: existing dams with hydropower generation storage, Group 2: existing dams without hydropower generation storage. Each group was further classified by the objective facility as shown in table below:

Table 3.4 Category of Group of Objective Dams

Financial Group Objective Facility Dam Countermeasures Scheme Group 1: existing 1) Hydropower dams Hydropower stations in ・ Rehabilitation and JICA ODA dams with under NPC Agus River, etc. upgrading of existing Loan/PPP hydropower 2) Hydropower dams Ambuklao, Binga, San hydropower JBIC generation owned by private Roque (Marubeni/Kanden) generation facilities loan/PPP storage, companies in Agus River, Kariraya ・ Countermeasures for (Sumitomo/J-Power), etc. reservoir 3) Multipurpose Pantabangan, Magat sedimentation JICA ODA dams under NIA ・ Dam life elongation Loan/PPP ・ Dam heightening Group 2: 4) Irrigation dams Irrigation dams in Bohol ・ Installation of small- JICA-PSIF, existing dams under NIA and others scale hydropower JBIC loan, without generator PPP hydropower generation storage. Source: The Study Team

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2) Selection Procedure

By adopting two stage screenings, 3 to 5 dams are selected at the first screening following the evaluation criteria. From among the 3 to 5 dams, another evaluation or screening is undertaken to select just one dam or one area for the feasibility study.

3) Evaluation Criteria

Evaluation criteria is prepared for two stages of first and second screening.

The evaluation criteria for the first screening of the Group 1 are; 1) site safety, 2) year after construction (sedimentation condition), 3) actualized problems and 4) socio-environmental issues, and for the Group 2 are 5) condition of rural electrification and 6) condition of reservoir operation in addition to 1)–4).

Consideration of Safety Issue in the Site

In most of areas in Mindanao, the alert level 2 (Travel discontinuation of nonessential) is issued by the Ministry of Foreign Affair of Japan. As for the dams in Mindanao, particularly those located in the high risk area, the site inspection of the study would have been avoided as much as possible. The study of these dams were conducted based on the interview survey to the central office and collection of data and information.

The evaluation criteria for the project selection includes the site safety.

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3.3 Outline of the Project

3.3.1 The Project Proposed

As the results of the study as mentioned in Section 3.4, “The Project for Restoration and Upgrading Dams in Bohol” is proposed for the pre-feasibility study considering the following reasons.

- selected as the highest priority through the project screening among the short-listed dams - there is a room to improve dam operation because of a lot of spill outs under present operation - needs for countermeasure for reservoir sedimentation - NIA has a plan to improve the existing spillway - potential for provision of new hydro-electric power plant (HEPP) to the existing dams which are utilized for irrigation water supply only, but not for hydro-electric power generation - consistent with the electrification policy in Bohol. At present Bohol island has connected to central grid of the electric power system, but power supply condition is still unstable. The demand for electricity is predicted to increase due to high potential of economic development in association with the opening of new airport. - increase of demand for eco-energy development

3.3.2 Purpose of the Project

The purposes of the Project are to contribute the local electric project and improve irrigation management through the formulation of the plan for restoration and upgrading dams in Bohol in cluding the following three (3) components;

1) Mini hydro-electric power developments in existing irrigation dams in Bohol 2) Improvement of operation of existing irrigation dams to reduce spill out and wasting water use 3) Countermeasures for reservoir sedimentation in Malinao Dam

3.3.3 Outline of the Project

Project Title

The Project for Restoration and Upgrading Irrigation Dams in Bohol

Scope of Works

A. Provision of hydro electric power plant in existing irrigation dams in Bohol

A-1 Malinao Dam HEPP : 290kW, 1,032 MWh/year

A-2 Diversion Chute HEPP : 1,038kW, 4,491MWh/year

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A-3 Bayongan Dam HEPP : 226kW, 630MWh/year

- Construction of hydro-electric power plant building - Installation of Y-shape distribution pipe at existing penstock - Installation of hydro electrical-mechanical works (turbine, generator, gate and operating system) B. Restoration of existing irrigation dams in Bohol

B-1 Improvement of operation of existing irrigation dams to reduce spill out and wasting water use

1) Revision of reservoir operation 2) Improvement of monitoring system (rainfall, water level, inflow, outflow, spillout, intake discharge, meteorological data, etc.) 3) Improvement of operation and management system of irrigation water use B-2 Improvement of existing spillway of Malinao Dam (already studied by NIA)

1) Heightening of existing spillway by installation of rubber gate of 2 m in height 2) Construction of a new auxiliary spillway 3) Heightening of a saddle dam B-3 Countermeasures for reservoir sedimentation in Malinao Dam

1) Construction of check dams in upstream tributaries 2) Construction of sediment flushing gate 3) Dredging/excavation of reservoir sedimentation 4) Installation of floating boom and rakes system at intake 5) Watershed management

Effects for Water Resource Development

- Increase of storage capacity of Malinao Dam : approx.2.0MCM (by raising NHL2m) - Reduction of spill out from Malinao : 6.4 MCM/year (from 33.4 MCM to 27.0MCM under proposed operation pattern D)

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3.4 Items of Necessary Studies

3.4.1 Project Selection Study

Basic Data Collection

Basic data related to the project was firstly collected through internet and reviewed by consultants. Data of the hydropower plants operated by Japanese company was collected directly from the operating company.

The list of data collection is presented below:

Table 3.5 List of Data Collection

Item Collected Information, Data Remarks I. Dam Renewable  Dams in Philippines(NWRMA,2000) Technology  Guideline for Advanced Technologies to Upgrade Dams under Operation (MILT-GOJ, 2018)  Ambuklao Dam Rehabilitation Plan(JICA, 1998)  Binga Dam Rehabilitation Plan(JICA, 1989)  The Study on Countermeasures for Sedimentation in the Wonogiri Multipurpose Dam Reservoir (JICA, 2008)  R.A 9136(Reform in the electric power industry) II. Irrigation  Miral site inspection photos 2018.Sep. 27  Lupao dam presentation (ppt and movie) 2018.Sep. 28  Drawings (Malinao, Bayongan, Capayas, 2018.Oct. 5 Talibon, Tangilad)  Dam operation data (Malinao, Bayongan, 2018.Oct. 5 Capayas, Talibon)  O & M Manual (Bohol II, Bayongan) 2018.Oct. 5  Tangilad SRIP presentation and photos 2018.Oct. 8  MARIIS hydropower potential site list 2018.Oct. 10 (Updated) 2018.Aug. 15  Hydropower potential site list (Updated) 2018.Aug. 15  SRIP dam list 2018.Aug. 15 (Hydropower)  2016-2020 Missionary Electrification 2018.Oct. 10 Development Plan III. Hydromechanical  Research on possibility for applying Japanese product IV. Economic/Financial Analysis  Republic Act No. 9513, Renewable Energy Act of 2008".  Public-Private Partnership (PPP) in the Philippines:A Handbook for  International Private Investors (12/2017)  Major Crops Statistics of the Philippines,2010- 2014 (PSA, Area, Yield,  Farmgate Price per Province))  Farmgate Price of Main Cereals (Country STAT

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Philippines, HP)  Purchase price of electricity of BOHECOII (Dec/2017-July/2018)  O&M cost of Malinao, Bayongan and Capayas Dams in the latest 3 years  Irrigated area and average yield of Malinao, Bayongan and Capayas Dams

V. Cost None Unit price of construction materials, equipment, labor cost, construction machine, etc. VI. Social and Environmental  Bohol Forest Land Use Plan

VII. Safety Evaluation  Safety Evaluation Report of Talibon, Malinao, Report Capayas and Bayongan Reservoir Dams (NIA, April 2012)  Dam Integrity and Safety Evaluation Reports of Magat Dam Complex (NIA, October 2010)  Dam Safety Review/Assessment of Pulangi IV hydroelectric Plant (NPC, May 2018) Source: The Study Team

Result of interview (Summary)

1) 【JICA Expert】

- It was explained that restoration and upgrading of dams utilizing Japanese Technology has already been introduced to NIA, NPC and SN Aboitiz by the JICA Expert. He confirmed that they were interested in countermeasures for reservoir sedimentation and upgrading of existing hydropower generation facilities. - In Philippine, many of dams are rock-fill dam and the restoration of such dams are more of a priority. - They confirmed that system between operator and owner during flood has a room for improvement.

2) 【Embassy of Japan】

- The scheme of this project is dam restoration focusing on the upgrading of existing hydropower generation facilities. However, Embassy of Japan thinks dam life elongation is vital and needs for the Japanese technology, therefore they suggested study team to consider it. - The potential of the development of hydropower plant is high, however it is difficult to choose dams of JMOFA level 3 in Mindanao taking into view for project conduction. Japan Embassy think that dams of JMOFA level 2 is even difficult to choose considering the public safety.

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- The field that is needed to introduce Japanese technology desperately tend to take STEP yen loan. - Japan Embassy thinks that 2 STEP yen loan is applicable for the project like Power Action Plan even if the counterpart is a private company. Therefore, any projects with appropriate reasons can be ODA projects. (Additional confirmation is needed because there are differences of recognition between EOJ and JICA Philippine office.)

3) 【NIA】

- There are continuous problems for reservoir sedimentation, therefore NIA suggested that it would be better to add it in the final output. - NIA has an intention to request Technical Cooperation Project targeting for dam operation and maintenance. - NIA suggested study team that it is desirable to select three dams from NIA (one dam from Luzon, Visayas and Mindanao respectively) in this study and conduct F/S.

4) 【NPC】

- Many of Power generation business of dams have already transferred to private company, whereas non-generation parts are still controlled by NPC. Regarding upgrading dams, if there are any requests from IPP companies, NPC consider it. Therefore, NPC has no plans to upgrade dams. - NPC thinks that If there is anything to select as representatives of this projects, Agus I,II or Pulangi would be best ones. NPC suggested study team not to select only one dam, but one dams from NPC and NIA respectively.

5) 【San Roque Power Company】

- Restoration of the hydropower plant is not timely at this point in time. They have just started overhaul three of its generators as well as restoration of its spillway this year. They had already planned for restoration of San Roque Dam fifteen years after its construction. - The Philippine government has no master plan regarding extent of power generation based on supply and demand. Planning was left to the private operators. Mr. Iseri however thinks it is the main oncern of the Philippine government.

6) 【CBK Power Company】

- is controlled by NPC and CBK is only conducting the operation. Therefore, discussion of the restoration of dams should be conducted between NPC. - Rehabilitation of Caliraya dam and hydropower station has already been started. There are no problems regarding the reservoir sedimentation.

7) 【SN Aboitiz Power Group (SNAP)】

- SNAP is operating the hydropower components of Ambuklao, Binga and Magat, and

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countermeasures for reservoir sedimentation was has already conducted for Ambuklao and Binga. Sedimentation has already reached the height of the new intake. Previously a countermeasure had been already undertaken by replacing the original intake and placed it at a higher level at new location. However, dredging has not been conducted. Deposition of silt is significantly progressing especially at Binga Dam, and therefore the immediate need for dredging. - SNAP is intensely interested in the Wonogiri project in Indonesia when study team showed it as an example of dam restoration. They showed intention to do site visit.

Suggestion toward the first and second screening

【Dams owned by NPC and operated by private companies】

1) Mindanao (Pulangi and Agus I, II)

Hydropower plant dams in Mindanao have actual problems of reservoir sedimentation and deterioration. NPC suggested that Pulangi and Agus I, II, where site safety risk level is relatively low are good representatives for this project. Selection of dams in Mindanao can get along with the local demand of electricity and might be able to lead to a short list for large-scale dam restoration project. However, there is a problem regarding the safety level.

2) Dams owned and operated by Japanese private companies (Caliraya and San Roque)

Caliraya dam and San Roque dam, which are managed by Japanese private companies conducts timely maintenance, rehabilitation and study. Therefore study team confirmed that they are not appropriate for this project in terms of timing of implementation.

3) Dams and hydropower plant owned and operated by private companies (Ambuklao and Binga)

Ambuklao and Binga Dams, which are under operation of SN Aboitiz were conducted intake reconstruction in 2011. However, it is not fundamental resolution for the problem of reservoir sedimentation and still they need countermeasures. SN Aboitiz suggested study team to select one of them especially Binga Dam.

Binga Dam can be a good representative for inclusion in the short list. However, a Norwegian company is presently undertaking research for its restoration. In addition, it is needed to confirm whether ODA is applicable for facilities owned by private companies. (Noted: The understanding of applicability of 2 STEP yen loan differs from each organization interviewed in this study.)

【Dams owned by NIA】

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4) Magat (MARIIS： Integrated Irrigation System)

Magat dam is owned and operated by SN Aboitiz, therefore it might be difficult to apply Japanese ODA. However, Baligatan hydropower plant (6MW) located upstream of MARIIS can be applicable it being owned and operated by NIA-MARIIS.

5) Capayas, Bayongan and Malinao

They were constructed under ODA and drawings and documents are easy to get.

Malinao was proposed for dam heightening and procurement for construction has been started and is in process. However, there are still rooms for consideration like application of machines and inspection equipment. Likewise, all of the three dams have no hydropower plant as yet and dam height and existing structures are high potential for hydropower.

6) Reservoir of SSRIP and SRISP

Dams of Small Reservoir Irrigation Project (SRIP), which target is under 1,000ha of irrigation area can be applied dam life elongation or installation of small-scale hydropower generator. However, water availability and inflow are erratic or not enough throughout the year. A better option would be hybrid development with such as solar power generation. Systems of floating solar power generation, which leads to reduce the breeding of algae by water quality conservation and prevention of water evaporation can be suggested.

Questionnaire Survey

Questionnaire sheet for upgrading dam under operation was distributed to NIA and NPC during the first field survey. Prior to the distribution of the sheet, the purpose and contents of the questionnaire was explained at the meetings with related agencies.

The questionnaire sheet is presented in Appendix 5, and the main item of questionnaire is shown in table below:

Table 3.6 Outline of Questionnaire

Main Item Contents of Questionnaire 1. General Information 2. Data/Information of Dams and  The number of dams (H>15m) under operations Hydropower Stations under  The number of hydropower stations attached with the dams operations (H>15m)  O&M Organization  Site safety of existing dams in case of proposed project implementation  Following data and information a. List and general information of dams and hydropower stations, if any. b. O&M budget data recent 10-years. c. O&M manual, if any. 3. Current issues of dam operation  Line up of the dams which have following issues, if any and damaged on the facilities a. Dams suffering from reservoir sedimentation

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b. Dams suffering from aging/deterioration or damaged on related facilities and apparatus. c. Dams which have operation and maintenance issues d. Dams which have social and environmental issues  Selection of current main issues of the dam operation 4. Reservoir Sedimentation  For the dams suffering from reservoir sedimentation, frequency of bathymetric survey, and request for providing survey or bathymetric results.  Brief explanation of land use conditions and management activities in the catchment area. 5. Plan/Project of Rehabilitation and  Experience of rehabilitation and improvement works Improvement Works  Brief explanation what kind of works is applied, for example, replacement of intake gate, reservoir dredging, etc. Source: The Study Team There were detailed replies from Miral Dam, Lupao Dam, and Calango Dam of NIA, and Dams Management Department of NPC Head Office and Dams, Reservoirs and Waterways Management Division, Operations Planning Department Mindanao Generation of NPC. The result of questionnaire is presented in Appendix 5.

First Screening for the Long-Listed Dams

After study team received the answer of questionnaire, the first screening for the long-listed dams was conducted. The long-listed dams is presented in Appendix 3.

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Table 3.7 List of Long-listed Dams (1/2) 21 23 19 19 17 12 15 18 19 19 16 18 18 18 19 20 20 18 18 18 19 Total Point 4 4 4 3 3 3 4 4 4 4 5 5 5 5 5 5 5 3 3 3 3 operation of reservoir of vi. Condition 1 1 1 2 1 1 1 1 3 2 2 3 3 3 3 3 3 1 2 1 1 v. Condition rural of electrificati on 3 3 3 3 3 3 3 3 1 3 3 1 1 1 2 2 1 3 3 3 3 ntal issues iv. Socio-iv. environme Evaluation Criteria 1 5 3 1 1 1 1 1 1 1 1 4 4 4 4 4 5 5 1 1 1 1 problems iii. Actualized 5 5 5 4 5 5 1 5 2 4 4 4 4 4 5 5 5 x 4 5 5 on After Constructi ii.Year 5 5 5 5 5 5 5 1 1 1 1 5 5 5 3 3 1 1 2 5 5 safety i. Site 48.00 78.00 258.00 247.00 288.00 usable (MCM) storage Reservoir 87.40 86.00 43.80 327.00 850.00 850.00 gross (MCM) storage Reservoir - - 70.1 67.00 568.00 452.00 215.00 240.00 140.00 173.60 Dam 1130.00 1070.00 Crest Length (m) - - - - Head 42.00 30.00 29.00 12.50 30.48 131.00 129.00 107.40 200.00 11 - 17 11 - =11.1m Height(m) - - TE TE TE ER ER ER ER ER ER ER CG Dam gravity Type of Overflow Overflow concrete concrete Concrete River Agno Agno Agno Agus Agus Agus Agus Agus Agus Angat Lumot Amlan Pulangi Caliraya Pagsanja n Cawayan Location Island Luzon Luzon Luzon Luzon Luzon Bohol Luzon Luzon Luzon Luzon Luzon /Lanao Negros / /Laguna /Laguna /Camarin /Sorsogo Mindanao Mindanao Mindanao Mindanao Mindanao Mindanao Mindanao Dam Dam Dam Dam ROR ROR ROR ROR ROR ROR ROR Dam ROR Dam Dam Dam Power Station Type of H H H H H H H H H H H H H H H H H Dams H,I,S,F H,I,S,F Purpose of AHC CBK NPC NPC NPC NPC NPC NPC NPC Power Power Power Station SNAPBI SNAPBI SNAPBI Company Mindanao Mindanao Mindanao Mindanao Mindanao Mindanao Mindanao Sta. Clara Sta. Clara Operator of CBK Power CBK Non- Non- Non- Non- NPC NPC NPC NPC NPC NPC NPC NPC NPC NPC NPC NPC NPC NPC NPC NPC NPC Owner NPC/IPP NPC/IPP NPC/IPP NPC/IPP 1956 1960 2003 1967 1983 1945 1979 1985 1983 1986 1948 1957 1959 1955 1958 1950 1985 n Year no info 1948 start 1992/1994 1953-1971 constructio Constructio Name of Dam Name of Ambukulao Binga San Roque Angat Kalayaan Pumped Storage Caliraya - dam Lumot - dam Agus I Agus II Agus IV Agus VI Agus VII Pulangi IV Botocan Buhi Barit Cawayan Loboc Amlan Talomo Tudaya *SNAPBI (SN Aboitiz Power Benguet, Inc.), SRPC(San Power Roque Corporation), AHC(Angat Hydro Corporation), CBKPC (CBK Power Company Ltd.) Agus V No. NPC NPC-01 NPC-02 NPC-03 NPC-04 NPC-05 NPC-06 NPC-07 NPC-08 NPC-09 NPC-10 NPC-11 NPC-12 NPC-13 NPC-14 NPC-15 NPC-16 NPC-17 NPC-18 NPC-19 (Other Source)

Source: The Study Team

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Table 3.8 List of Long-listed Dams (2/2) 16 13 16 19 18 19 16 12 12 21 19 15 15 14 16 20 20 14 14 14 14 18 20 19 16 22 19 15 15 15 20 14 14 15 3 3 3 3 3 3 1 2 2 3 3 3 3 3 3 3 3 3 3 3 3 2 3 3 2 5 5 3 3 3 3 3 3 3 1 1 1 1 1 1 1 3 3 2 2 2 2 2 1 1 1 1 1 1 1 2 2 2 3 1 1 2 2 2 3 3 3 2 3 3 3 2 2 2 3 3 3 3 3 1 1 1 3 3 3 1 1 1 1 3 3 3 3 3 3 1 1 1 3 1 1 1 x x x 3 3 3 1 1 1 5 5 1 1 1 1 5 5 1 1 1 1 1 5 5 1 4 1 1 1 1 5 1 1 1 4 1 4 5 4 5 5 1 1 3 3 3 3 2 3 3 3 3 3 3 3 5 2 1 5 4 4 3 3 3 3 3 3 3 5 5 5 5 5 5 5 2 2 5 3 5 5 5 5 5 5 5 5 5 5 5 5 5 2 5 5 5 5 5 3 3 3 5 6.00 51.00 1,250.0 2,996.0 - - 22.00 845.00 855.00 450.00 4160.00 1615.00 - - 5.50 1.00 26.00 32.00 29.00 16.00 12.50 27.00 28.50 30.00 21.00 21.50 27.00 25.00 20.40 35.50 33.00 10.00 38.00 25.00 17.00 21.50 27.00 32.25 29.00 25.00 114.00 107.00 - dam Dam Dam Weir Dam Dam Dam Dam Dam Dam Dam Dam Dam Weir Earth Gravit y Gravit y Filltype Earthfill /Rockfill /Earthfill /Rubber? Concrete Diversion /Concrete - Claveria Angat Zapote Pampang a Canili Cateel Pampang a Angat Tullahan Agusan Magat Wahing Casecna n Iloilo Cebu Cebu Luzon Bohol Bohol Bohol Bohol Bohol Bohol Luzon Luzon Luzon Luzon Luzon Luzon Luzon Luzon Luzon Luzon Luzon Luzon Luzon Luzon /Davao Negros Negros Negros Negros /Aurora Mindanao Mindanao Mindanao Mindanao Mindanao Mindanao Dam Dam None None None None None None None None None None None None None None None None None None None None None None None None I I I I I I I I I I I I I I I I I I I I I - I I I S S H H S I, H I, H Irrigation Irrigation Non- None None None None None None None None None None None None None None None None None None None None None None SNAP Hector NPC/IPP NPC/IPP First Gen MINERGY - - - NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA NIA District Metro Cebu 19th 1912 1974 1926 1984 1929 1957 2014 2012 1982 2007 1992 1994 1995 1995 1994 1981 1998 2002 1981 around Century Pantabangan Bustos Ipo La Mesa Prinza (Molino) Buhisan dam Agusan Dam Aragon Dam Cabulig Bayongan (Bohol II) Capayas (Bohol II) Magat Acop Lupao Tanguilad Aulo Alapasco Ilaya Capayas Calango Nasig-Id Talibon Miral San Angel Masidem Kitcharao Can-Asujan Dauin Binalawan Canili /Diayo Dam Malinao (Bohol I) Casecnan Masiway O-01 O-02 O-03 O-04 O-05 NIA-02 NIA-I03 NIA-I04 NIA-I01 NIA-I02 NIA-I05 NIA-I06 NIA-S01 NIA-S02 NIA-S03 NIA-S04 NIA-S05 NIA-S06 NIA-S07 NIA-S08 NIA-S09 NIA-S10 NIA-S11 NIA-S12 NIA-S13 NIA-S14 NIA-S15 NIA-S16 NIA-S17 NIA-S18 NIA-M01 NWSS-01 NWSS-02 NWSS-03 NIA (Multi Purpose Dam) NIA (Irrigation Dam/SRIP) NIA (Irrigation Dam) NWSS Others Source: The Study Team

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1) Weight for 1st Evaluation Criteria

Following weighting of each evaluation criteria of the first screening is applied:

i) Site safety Safety Level Level 3 Level 2 Level 1 (GOJ) Point 1 3 5 ii) Year After Construction Year after 0-10 year 11-20 year 21-30 year 31-50 year >51 year construction Point 1 2 3 4 5 iii) Actualized problems Actualized None Fair Minor Medium Serious Problem Point 1 2 3 4 5 iv) Socio-environmental issues Actualized Serious Minor Fair None Better Problem Point 1 2 3 4 5 v) Condition of rural electrification Area Luzon Bisayas Mindanao Point 1 2 3 vi) Condition of reservoir operation Better by Condition of Better (operation reservoir Not good Fair Good (operation by operation by IPPA) NPC/NIA) Point 1 2 3 4 5

2) Result of First Screening

After study team received the answer of questionnaire, the first screening for the long-listed dams was conducted.

The result of the first screening is presented below. As the result, following dams were selected as the shot-listed dams:

Table 3.9 Summary of First Screening of Objective Dams v. vi. ii.Year iii. iv. Conditio Conditio Actualiz Socio- No.. Name of i. Site After ed environ n of n of Total Dam safety Constru rural reservoir Point ction problem mental electrific operatio s issues ation n Ambuklao NPC-01 5 5 3 3 1 4 21 Dam

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NPC-02 Binga Dam 5 5 5 3 1 4 23

NIA-M01 Magat Dam 5 4 4 3 1 5 22

NIA-S02 Lupao Dam 5 3 5 3 1 3 20

NIA-S03 Tanguila 5 3 5 3 1 3 20

NIA-S11 Miral Dam 3 3 5 3 3 3 20 Malinao NIA-I04 5 2 5 3 2 3 20 (Bohol I) Bayongan NIA-I05 5 1 5 3 2 3 19 (Bohol II) Capayas NIA-I06 5 3 5 3 2 3 21 (Bohol II) Source: The Study Team

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Source: The Study Team

Figure 3.1 Location Map of Shor-Listed Dams

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Basic Study and Site reconnaissance for Short-listed Dams

Site reconnaissance for the short-listed dam are carried out to study and assessment of following items:

1) Dam

 Stability of dam body  Topography and geology (Erosion, Land Slide, etc.) of surrounding areas of dam  Watershed condition

2) Spillway

 Topography and geology of spillway site  Structural stability of spillway (guide wall, energy dissipator)  Flow capacity of spillway

3) Reservoir

 Sedimentation  Landslides along the perimeter of the reservoir

4) Power Station (civil and architecture)

 Structural stability of power station  Topography and geology of power station site

5) Mechanical equipment and pipe/penstock

 Conditions of valve and gate  Operating equipment  Conditions of turbine and generator A. Reservoir/Watershed 1) Sedimentation condition 2) Landslide around reservoir 3) Watershed B. Dam body 1) Safety of the dam body 2) Topography and geological aspect (erosion, landslide etc.) of the dam area around the dam body

Ｃ．Flood discharge 1) The topography and geological aspect of natural ground 2) Safety of structures 3) Capacity of spillway E. Mechanical Equipment and Pipe/ Penstock Ｄ ． Power plant (civil engineering / 1) Conditions of Valve and Gate construction) 2) Operating Equipment 1) Stability of power plant main body 2) Topography and geological aspect of 3) Conditions of Turbine and Generator the power stations surrounding area 4) Monitoring equipment

Source: The Study Team

Figure 3.2 Main Items Investigated during Site Reconnaissance Nippon Koei Co., Ltd. 3-19 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Project Components and Technical Study Main Report Chapter 3

1) Dams under Private Companies: [Ambuklao Dam, Binga Dam (NPC/SNAP)]

i) Project profile - In the upper Agno River Basin, there are three (3) cascade dams, namely Ambuklao, Binga and San Roque Dams. Ambuklao and Binga dams are the dam for hydroelectric power plant, which were privatized from NPC to SNAP (SN Aboitiz Power) in 2007. - Construction of the Ambuklao Dam was started in 1950 and become operational in 1956 financed by the IBRD. The dam is an earth and rockfill dam with height of 129.0 m. It serves as a single-purpose dam for hydropower with an installed capacity of 75MW. - The Binga Dam is situated 19 km downstream of the Ambuklao Dam. Construction of the dam began in 1956 and become operational in 1960 financed by IBRD. The dam is an earth and rockfill dam with height of 107.4 m. Like Ambuklao Dam, Binga Dma serves primarily as hydropower generation plant with an installed capacity of 100 MW. - In 1988, JICA completed the rehabilitation studies of Ambuklao an Binga Dams. The reports stated that several recommendations for rehabilitation works in each dam. - After the Baguio Earthquake in 1990, Ambuklao Dam had been decommissioned in 1999 due to serious sedimentation problem at intake. In 2007, both Ambuklao and Binga Dams were privatized from NPC to SNAP, and the rehabilitation of hydromechanical works and replacement of the intakes had been conducted. At present operation and maintenance of both dams are being undertaken by SNAP. - Intake reconstructions were down both Ambuklao and Binga Dams in 2011. However, it is not fundamental resolution for the problem of reservoir sedimentation and still they need countermeasures. SNAP suggested the study team to select one of them especially Binga for the candidate project of the pre-feasibility study to be implemented. ii) Results of site reconnaissance (Binga Dam) - Catchment area of the dam is situated in active sediment productive areas where a lot of slope failures and small landslides occurs. Progress of reservoir sedimentations are very serious both in Ambuklao and Binga Dams. - SNAP carries out bathymetric survey every year since 2007. Historical change of reservoir sedimentation conditions is recorded and analysed. As per result of the survey in 2017, effective storage capacity of 95.1 MCM has been decreased to 13.9 MCM, and dead storage of 69.9 MCM has been reduced to 7.3MCM. Likewise, the flood control storage (*dam has no flood control function, but it is considered having it above the effective storage capacity) is also reduced. - No visible deformation, damage and seepage are observed on the dam body. But there is a decline in dam safety level due to earth pressure of sedimentation on upstream

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slope of dam. In addition, because of reduction of flood control storage, there might be potential risk for dam overtopping in case of extra ordinary flood - An old intake has been decommissioned and new one has been constructed in 2011. The new intake is used like a run-off river type because its sill elevation was raised above the sedimentation level. So far there is no significant reduction of power output because the operational storage capacity for peaking power is still available. - The intake gate is closed in case the turbidity of intake water become high in order to protect from abrasion and damage on intake, headrace and turbine. - Sto. Nino River which is a tributary from right upstream basin is the one of the biggest sources of sediment inflow into the reservoir. At the confluence, sediment shoulder is formed where many boulders and cobble stones are deposited. At present this location is used as query site. According to Barangay Captain, hauling volume is around 30 units of dump truck in daily average. The excavated materials can be sold for construction materials. - Hydro-mechanical works were rehabilitated at the time of privatization, and are well maintained at present. The original spillway gates are still used without replacement while only lifting equipment was replaced.

Outlet of Ambuklao PS

Binga Dam

2017 1960

95.1 13.9

69.9 7.3

Source : Sedimentation data from SN Aboitiz Power

Figure 3.3 Reservoir Sedimentation in Binga Dam

iii) Needs for dam restoration and upgrading - Needs for dam restoration and upgrading is high

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- As a countermeasure to recover reservoir storage capacity, study for advanced integrated dam operation among Ambuklao- Binga-San Roque and reallocation of dam storage capacity shall be necessary. In the future, dam heightening is being proposed as one of applicable measures, but would require very detailed studies and geotechnical investigation. - There is a decline in dam safety due to earth pressure caused by sediment deposits over the dam upstream slope. For flood control, the dam should be given special attention because of sedimentation in flood control storage. As for dam upgrading, reinforcement of the dam body and increase of flood control capacity of the spillway would be necessary as countermeasures. - For sedimentation countermeasures, sediment releasing (flushing and bypassing) from the dam is difficult to be considered because there is San Roque Dam that would trap the released sedimentation in the downstream river. SNAP has just started the stakeholder meeting for integrated sediment management. - There was a proposal to construct check dams in the upstream basin, but not realized yet. Taking into the present query activity, it is recommendable option to address the problem by constructing check dams in Sto. Nino River and carrying out open excavation in upstream of the check dams. It could be also provided mini hydropower with the check dam.

Source : The Study Team

Figure 3.4 Location Map of Ambuklao and Binga Dams

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Date：Oct. 17, 2018 Date：Oct. 17, 2018 Location：Dam and Reservoir (Ambuklao) Location：Spillway (Ambuklao)

Date：Oct. 17, 2018 Date：Oct. 17, 2018 Location：New Intake gate (Binga) Location：Spillway (Binga)

Date：Oct. 17, 2018 Date：Oct. 17, 2018 Location：Downstream slope of dam (Binga) Location：Upstream slope of dam (Binga) Source : The Study Team

Figure 3.5 Site Photos of Ambuklao and Binga Dams

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2) Dams Under NPC: [Pulangi Dam in Mindanao]

i) Project Profile There are six (6) hydropower plant projects envisioned for development by NPC along the Pulanggi Rive which is the second largest sub-basin of the Mindanao River Basin. The firstly developed one was the Pulanggi 4 Dam project in , in 1986. The dam is an earth-fill dam of 11 – 17 m in height and featured by a concrete spillway 28.0 m high and 140 m long, located at the midspan of the left and right embankment of an earth-fill dam.

Source : The Dams in Philippines (NWRB)

Figure 3.6 Location Map of Pulangi Dam

ii) Results of site reconnaissance (*conducted by local experts due to security condition) - There is sedimentation problem mainly due to land conversions and plantations at the watershed. Dredging of sediments at reservoir was contracted out and has finished Phase III. Total dredged volume is estimated around 500,000 m3. Dredging machine is still working at the reservoir area. iii) Needs for dam restoration and upgrading - A “Safety Review and Development” was just conducted by Engineering and Dev. Corp. of the Philippines this year 2018. No major threat of the dam was reported. - Spillway gates show leaks caused by dirt deposits. There is needs for maintenance of dam facilities.

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Source : The Study Team

Figure 3.7 Site Photos of Pulangi Dam

3) Multipurpose Dam Under NIA: [Magat Dam]

i) Project profile - Magat Dam is multipurpose dam constructed in Isabela Province in 1982. The dam is considered one of the biggest in Asia located in the Magat River which is the largest tributary of the having a catchment area of 4,631 km2. - The dam is a zoned earth and rockfill with inclined core with 114 m in height, 4,160 m in length, and storage capacity of reservoir is 1,250 MCM. - The reservoir storage is used for irrigation water supply for the Magat River Integrated Irrigation System (MARIIS) and used for Magat Complex hydropower facilities in the dam sites and its irrigation canals.

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Table 3.10 List of Magat Complex HEPPs

Completion Installed Owned and Name of HEPP Location Year Capacity operated by Magat HEPP Magat High Dam 1983 360.0MW SNAP since 2007 MARIIS South Canal Maris Diversion Dam 2018 8.5MW SNAP HEPP Baligatan HEPP Baligatan Dam 1985 6.0MW, NIA Magat A HEPP Magat main canal 1984 1.44MW ISELCO A micro HEPP Magat secondary canal 2013 under 0.12MW, NIA; on-going (Lateral B) JICA Grant electricity Project sales procedure Source : The Study Team

ii) Results of site reconnaissance - Sediment yield in the watershed is increasing after 1990 Baguio Earthquake. However, the sedimentation level is still within the dead storage, so far no serious problem. - Dam observation, monitoring and warning system are well maintained. Each division of the service area has rainfall observation system, but 3 systems are malfunction at present. - In the reservoir, there is a floating solar system with 2,500 m2 in area will be installed for trial operation from January 2019. Generated power will be used by self consumption in SN Aboitiz facilities. iii) Needs for dam restoration and upgrading - Magat Dam and its facilities are well maintained, and so far sedimentation becomes not serious problem. The need for dam restoration and upgrading is low. - Outflow of Baligatan HEPP enters to Kalao River, and flow down to Baligatan regulating pond located in around 4km downstream of the Baligatan Dam. There is a potential development site for min hydro-electric power plant using the head difference of around 30 m between these locations and 23.4 m3/s of outflow from the Baligatan HEPP. - In addition to the above, there are several potential sites for development of micro hydroelectric power plant along the irrigation secondary canals in MARIIS. - Water level observation has been done by manual in the mini HEPPs in irrigation canals. There is a possibility to install telemetering observation system. Some malfunctioning generators and turbines will be replaced by the operators.

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Magat South MC Lateral B

Magat dam

Magat A Baligatan intake Potential site

Baligatan

Source : The Study Team

Figure 3.8 Location Map of Magat Dam Complex and HEPPs

Date：Oct. 10, 2018 Date：Oct. 10, 2018 Location：Outlet (Micro HEPP) Location ：Control house and substation facility (Micro HEPP)

Date：Oct. 10, 2018 Date：Oct. 10, 2018 Location：Overall view (Baligatan HEPP) Location：Generator (Baligatan HEPP)

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Date：Oct. 10, 2018 Date：Oct. 10, 2018 Location：Upstream (potential site d/s Baligatan HEPP) Location ： Downstream (potential site d/s Baligatan HEPP)

Date：Oct. 10, 2018 Location：Overall view (MARIIS South Canal HEPP) Source : The Study Team

Figure 3.9 Site Photos of Magat Complex HEPPs

4) Irrigation Dam under NIA: [Irrigation Dams in Bohol, Malinao/Bayongan/Capayas Dams]

There are three (3) irrigation dams in eastern Bohol Island, namely Malinao Dam, Bayongan Dam and Capayas Dam, which were constructed by Japanese ODA. These dams are inter- connected through the Malinao main canal, Malinao diversion chute and Bayongan main canal as shown in the figure below. Malinao dam has a bigger inflow but smaller storage while Bayongan dam has smaller inflow but bigger storage. The basic irrigation development plan is an integrated water management considering how to regulate the Malinao inflow and to divert flow to the downstream Bayongan Reservoir and to the further downstream Capayas reservoir. No hydroelectric power plants are installed in these dams.

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Source : The Study Team

Figure 3.10 Profile of Dams in Bohol Irrigation Project

5) Malinao Dam

i) Project profile - Malinao dam is a rockfill dam with height of 20.4m. The dam was constructed under Japanese ODA (Yen Loan Project) in 1996. ii) Result of site reconnaissance - In Malinao dam located in the most upstream of the Bohol Irrigation Project, spillout often occurs in every rainy season. Spillway outflow from the dam is released to the downstream of the Wahig River eventually flowing out to the ocean. It is an dam operational issue to reduce volume of wasting water by spillway outflow. - Sedimentation is in progress in surrounding area of intake and identified as one of dam management issues. Desilting of 15,000 m3 and spot elevation survey were conducted in 2018. - Clogging of the intake due to sedimentation is not actualized problem at present, but clogging of the screen at intake due to floating logs and debris becomes problem at the time of flooding. Removal of debris over the intake screen is done by divers. During the removal works, irrigation water supply from the dam is stopped for around 2-3 days. Floating logs can be removed toward the spillway forebay using a chain block at the intake gate. iii) Needs for dam restoration and upgrading - There is a plan to improve existing spillway to gated one with rubber gate and to raise NWL by 2 m. In addition, new axially spillway will be constructed considering the

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climate change impacts. According to NIA, local consultants had completed the design of spillway improvement works and the bidding of construction works will be conducted within this year. - It is necessary to study structural safety of dam and spillway in connection with raising NWL by 2m as well as the review study for water balance and water use plan. - Intake outflow is controlled with a butterfly valve at the outlet. There is a possibility to develope a mini hydroelectric power plant at the outlet. The maximum head is estimated at 7 m (El. 152.00 m -EL.145.00 m), maximum discharge is 11.8 m3/s. The required construction space is available because the location is within the right of way limit of NIA. The electricity to be generated will be sold to a local power distribution company (BOHECO2). - There is a diversion chute connecting from Malinao main irrigation canal at Sta. 18+480 to the upstream of Bayongan reservoir. The diversion chute is a slope type water way having a large elevation difference of around 80 m between the canal and reservoir. There is a possibility to install a mini hydroelectric power plant at the diversion chute, the maximum head is estimated at 75 m (El. 127 m -EL. 52m) and maximum discharge is 11.8 m3/s. - According to NIA, TEPSO has conducted an investigation for hydro power development of the diversion cute based on the MOU made between NIA and TEPSCO.

Intake

Spillway Dam

Source : Nippon Koei.co., Ltd

Figure 3.11 Layout Plan of Malinao Dam

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Date：Oct. 02, 2018 Date：Oct. 02, 2018 Location：Outlet Location：Outlet steel pile with a butterfly valve

Date：Oct. 02, 2018 Date：Oct. 02, 2018 Location：Spillway (inlet) Location ： Malinao Shute connecting to Bayongan Reservoir Source : The Study Team

Figure 3.12 Site Photos of Malinao Dam

6) Bayongan Dam

i) Project profile - Bayongan Dam is a rockfill dam with height of 31.0m. The dam was constructed under Japanese ODA (Yen Loan Project) in 2007. ii) Result of site reconnaissance - Planned irrigation area is 4,170 ha but it is only 3,063 ha now. It was planned to supply water from Bayongan Dam to the downstream Capayas Dam, but water is short and not reach to Bayongan Dam. Conversely, there are cases where wastewater of Capayas Dam is distributed to the irrigation area of Bayongan. - Sedimentation inflow volume is less because of small catchment area (14.6 km2) and good watershed management conditions. iii) Needs for dam restoration and upgrading

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- As same as the Malinao Dam, intake outflow is controlled with a jet-flow gate at the outlet, and there is a possibility to develope a mini hydroelectric power plant. The maximum head is estimated 12 m (El. 52.0 m -EL.40.0 m), maximum discharge is 9.74 m3/s. The required construction space is available in the area owned by NIA.

Date：Oct. 03, 2018 Date：Oct. 3, 2018 Location：Dam Body Location：Outlet (emergency Gate) Source : The Study Team

Figure 3.13 Site Photos of Bayongan Dam

7) Capayas Dam

i) Project profile - Capayas Dam is a rockfill dam with height of 31.0m. The dam was constructed under Japanese ODA (JICA Grant Project) in 2007. - In 1997, dam and spillway were heightened by 2 m, and NWL was raised by 2 m. ii) Result of site reconnaissance - No sedimentation problem because of small catchment area (2.2 km2) and good watershed management conditions. - The planned irrigation area of 750 ha is irrigated as planned, and water discharge and dam water level are observed by visual contact and recorded manually. iii) Needs for dam restoration and upgrading - Inspection of intake canal is very difficult because the existing intake is a morning growly type without gate. If sedimentation is progressed in the future, replacement to intake tower shall be considered. - As same as the Malinao Dam, intake outflow is controlled with a valve at the outlet, and there is a possibility to develope a mini hydroelectric power plant. The maximum head is estimated 10 m (El. 36.5 m -EL.26.5 m), maximum discharge is 6.0 m3/s.

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Date：Oct. 03, 2018 Date：Oct. 03, 2018 Location：Outlet Location：：Spillway (upstream) Source : The Study Team

Figure 3.14 Site Photos of Capayas Dam

8) Small Irrigation Dams under NIA: [Lupao Dam, Tangilad Dam]

9) Lupao Dam

i) Project profile - Lupao Dam was constructed under SRIP in Province of Nueva Ecja in 1994. The dam is an earthfill dam with 17 m in height. ii) Result of site reconnaissance - Sedimentation level has already reached to intake top level. At present, the dam is just operating as run-off-the river and not as storage dam. The planned irrigation area is 975 ha but actual one is only about 90 ha. Water discharge and dam water level as well as other hydro-meteorological data have not been observed. - In 2009, Typhoon Ondoy had brought huge amounts of sediments in the reservoir. Because there was a risk of clogging intake, the intake gate and outlet gate have been kept open and released water to the main channel without any regulation. - In 2012, NIA conducted dredging in surrounding area of the intake by around 7 m in thickness, and constructed a silt protection dike made with gabion in front of the intake. However, by Typhoon Malio in 2014, the intake area was covered with sediment depositions and again sediment level has reached to intake top level. - Spillway has not been used since 2012. iii) Needs for dam restoration and upgrading

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- The needs for dam restoration and upgrading is high. For proposed projects, replacement of the intake can be considered. Main concept is presented below: i) LWL shall be raised above the present sedimentation level. Based on the revised LWL, a new intake tower shall be designed. Location of the new intake can be proposed at upstream of the existing intake. ii) From the new intake tower, new intake tunnel and new outlet shall be constructed at left abutment area of the dam. iii) Existing intake tunnel can be used as a sediment flushing tunnel. Sediment to be deposited in front of the new intake could be periodically released By using this flushing tunnel. iv) To mitigate sediment inflow from the upstream basin, watershed management programs shall be continued. In addition, check dams shall be restored, and periodical sediment removal shall be conducted at upstream of the check dams. Removed sediments can be reused for construction materials. Existing spillway gate shall be rehabilitated. v) In the new outlet site, there is a possibility to install a mini hydroelectric power plant using the irrigation water.

- In case of upgrading of the Lupao Dam, drastic countermeasures for sedimentation are required. On the other hand, there is a plan for construction of new dam in the adjacent basins. It is necessary to assess integrity between the plans if the sediment countermeasures plan will be in line with the new dam development plan and irrigation program. At this time, dam operation records such as reservoir water level, intake discharge, outflow, As Built Drawings and reservoir sedimentation data cannot be collected because they have been dissipated. Because of such conditions, it is considered difficult to conduct prefeasibility study for the Lupao Dam in this study.

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Source : The Study Team

Figure 3.15 Location Map of Lupao Dam

Intake Dam Spillway

Date：Sep.28, 2018 Location：Lupao Dam Reservoir

Date：Sep.28, 2018 Date：Sep.28, 2018 Location：Check Dam (damaged) Location：Upstream river Source : The Study Team

Figure 3.16 Site Photos of Lupao Dam

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10) Tangilad Dam

i) Project profile - Tangilad Dam was constructed under SRIP in Province of Bataan in 1988. The dam is a zone earthfill dam with height of 28.5 m. ii) Result of site reconnaissance - Sedimentation is in progress. Desilting was conducted in 2017. It was the first time since dam construction. - Intake is morning growly type which is not affected by sedimentation yet. - In 2013, spillway was improved to the gated spillway and NWL was raised by 2 m. But no heightening of dam body and no improvement of spillway chute were carried out. - There is no dam operation record except for after 2018 July. - Gate house at outlet was deteriorated. iii) Needs for dam restoration and upgrading - Since the spillway improvement has been completed, the necessity of dam upgrading is low. - There is a gate installed at the outlet. A penstock upstream of the outlet gate is y-shape distribution because of temporary diversion during the dam construction. At present, branch side of the penstock was plugged. There is a possibility to install a mini hydroelectric power plant using the irrigation water.

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Source : The Study Team

Figure 3.17 Location Map of Tangilad Dam

Date：Oct.8, 2018 Date：Sep.28, 2018 Location：Dam Body Location：View from Downstream Source : The Study Team

Figure 3.18 Site Photos of Tangilad Dam

11) Miral Dam

i) Project profile - Miral Dam was constructed under SRIP in Province of Davao Oriental in 1994. The dam is an earthfill dam with 27 m in height. ii) Result of site reconnaissance (*by local experts due to security condition) - The dam reservoir is heavily silted. The intake is completely clogged with sediment. Massive vegetable farming is ongoing at the watershed. - Sedimentation of 3,000 m3 and 3,400 m3 were already dredged during the year 2009 and 2010, respectively.

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- There is bifurcation at the outlet. One is being used for intake outlet and another is intended for hydropower but not used. iii) Needs for dam restoration and upgrading - NIA conducted the Dam Safety Inspection of the Miral Dam in 2018. - The needs for dam restoration and upgrading is high. For proposed dam restoration and upgrading projects, replacement of the intake can be considered. Main concept is presented below: i) A new intake tower shall be constructed at left upstream abutment of the dam. From the new intake, new intake tunnel and new outlet shall be constructed ii) Existing intake tunnel can be used as a sediment flushing tunnel. Sediment to be deposited in front of the new intake could be periodically released By using this flushing tunnel. iii) Existing spillway can be used if the spillway gate is rehabilitated. iv) In the new outlet site, there is a possibility to install a mini hydroelectric power plant using the irrigation water.

Source : NIA

Figure 3.19 Location Map of Miral Dam

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Date：Oct.3, 2018 Date：Oct.3, 2018 Location：Heavily silted reservoir Location: Spillway

Date：Oct.3, 2018 Location：Panoramic view of Dam Source : The Study Team

Figure 3.20 Site Photos of Miral Dam

The main findings of site reconnaissance are summarized in following tables.

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Table 3.11 Main Findings of Site Reconnaissance (Reservoir Sedimentation)

Dam Main Findings (Reservoir Sedimentation) Sedimentation problem started upon construction of main road thus human Ambuklao Dam settlements increased and soil cultivation. Also the strong earthquake that occurred in 1985 started massive sedimentation unto the river. Binga Dam sits below Ambuklao and the receiver of all the sedimentation problem. Binga Dam As reported it has 2.0 MCM silt and siltation is estimated at 100,000 Cu meters per year. It has a serious sedimentation problem. There is sedimentation problem mainly due to land conversions and plantations at the watershed. Pulangi Dam Dredging of sediments at reservoir was contracted out and has finished Phase III. Some 500,000 MCM sediment already dredged. Dredging machine is still at the reservoir area. It uses bottom sluice to flush out sediments out to the old river. Sediment yield in the watershed is increasing after 1990 Baguio Earthquake. Magat Dam However, the sedimentation is still be low dead storage, so far no serious problem Sedimentation level has already reached to intake top level. Lupao Dam At present, dam storage function is not working, just used as ROR. because the outlet valve was removed. And Sedimentation is in progress. Desilting was conducted in 2017. It was the first time Tanguilad since dam construction. Intake is morning growly type which is not affected by sedimentation yet. The dam reservoir is heavily silted. The intake is completely clogged with sediment. Massive vegetable farming is ongoing at the watershed. In fact the source of water of Miral is diverted to vegetable farms. Improper cultivation along the slope must be Miral Dam stopped as it easily erodes topsoil thus significantly contributing to sedimentation. 3,000 cu meters and 3,400 cu meters of sediments already disposed during the year 2009 and 2010, respectively. Sedimentation is in progress in surrounding area of intake. Desilting and survey was conducted in 2018. Malinao (Bohol) Spill out often occurs in wet season due to reduction of storage caused by sedimentation Bayongan (Bohol) No problem due to small catchment area Capayas (Bohol) No problem due to small catchment area Source: The Study Team

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Table 3.12 Main Findings of Site Reconnaissance (Dam Safety)

Name of Dam Dam Body Spillway Intake Outlet No visible damage, The downstream The old intake No Problem deformation and seepage. of spillway slowly already covered Decline in dam safety level scouring the and clogged. A Ambuklao Dam due to earth pressure of mountain wall. new intake was sedimentation on upstream constructed. slope of dam. No visible damage, Because of The old intake No problem deformation and seepage. reduction of flood already covered Decline in dam safety level control storage, and clogged. A due to earth pressure of there might be new intake was Binga Dam sedimentation on upstream potential risk for constructed. slope of dam. dam overtopping In case of extra ordinary flood A “Safety Review and Spillway gates No Problem No Problem Development” just shows leaks caused conducted by Engineering by dirt deposits. Pulangi Dam and Dev. Corp. of the Needs maintenance Philippines this year 2018. No major threat of the dam was reported. Dam safety should be There is fault at The right side of closely monitored. Some downstream of dam has a leading No Problem. instruments are damaged and spillway. Needs channel which It is always need maintenance and close monitoring. diverts water to opened to replacement. Baligatam Dam. It sluice some Magat Dam has to be sediments. maintained as it may affect operation of irrigation and Baligatan Power. The spillway was completely Spillway has not It is the only It is kept clogged and impedes water been used since means of open and to pass through due to heavy 2012.No longer releasing water to release sedimentation. operating as it was the river and main water to a Continuous completely clogged channel. It has regulating Lupao Dam sedimentation may reach to a by sedimentation. the risk of being pond and point where the inlet might clogged. It is into the be also be clogged and pose always open. main a great danger channel. of overtopping.

In 2013, spillway was Structural safety Structural safety Gate house improved to the gated and flood control of intake tower at outlet was spillway and NWL was capacity of new shall be deteriorated. raised by 2m. gated spillway shall confirmed. But no heightening of dam be confirmed. Inspection of Tanguilad body and no improvement of intake canal is spillway chute were carried very difficult out. The safety of dam shall because intake is be assessed considering the a morning growly dam improvement works. type. Miral Dam No Problem, but siltation The only exit of The intake is No water is

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Name of Dam Dam Body Spillway Intake Outlet must be closely monitored to water to the river completely coming out. avoid risk of overtopping. and main channel. clogged by It is It is kept open. sediments. completely clogged. Water is released through the spillway. There is a plan to improve Structural safety Structural safety Structural existing spillway to the gated and flood control of intake tower safety of one and to raise NWL by 2 capacity of new shall be studied. outlet shall m. gated spillway shall be studied. In addition, new axially be studied. spillway will be constructed Malinao(Bohol) considering the climate change impacts. Study for structural safety of dam and spillway is necessary in connection with raising NWL by 2m. So fa no problem for safety same as left No problem No problem Bayongan(Bohol) on dam(structure) and spillway (flood) In 1997, dam and spillway Structural safety Structural safety Structural were heightened by 2 m, and and flood control of intake tower safety of NWL was raised by 2m. capacity of new shall be studied. outlet shall The safety of dam shall be gated spillway shall Inspection of be studied. Capayas (Bohol) assessed considering the dam be studied. intake canal is improvement works. very difficult because intake is a morning growly type. Source: The Study Team

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Table 3.13 Main Findings of Site Reconnaissance (Condition of Operation and Maintenance)

Name of Dam Civil Irrigation Hydro-Mechanical

Ambuklao Dam Dam slope, spillway and n/a No problem other civil facilities are well maintained. Binga Dam Dam slope, spillway and n/a No problem other civil facilities are well maintained. Pulangi Dam Dam slope and other civil n/a Spillway and other structures are well movable gates show maintained. However the rust that needs presence of growing trees maintenance. and shrubs may be a source of soil cracks and dam stability.

Magat Dam Dam slope, spillway and It has an irrigated area of Spillway gates are other civil facilities are well 85000 ha, fishery and well maintained. maintained. drinking water are also Some monitoring provided instruments are Recently solar power damaged and need generation development on maintenance and tourism dam and tourism replacement. resource development are also carried out. As a result, the economic effect of the proper operation of the dam is high. Lupao Dam Only minor maintenance The sedimentation of the Spillway gate was works have been done. reservoir has progressed, damaged and required and it doesn't store water at maintenance. present. The planned irrigation area 900 ha but actual one is only about 90 ha. Water discharge and dam water level aren't observed. Tanguilad Upstream slope is protected Since rehabilitation of Original spillway was with riprap. spillway by GOP irrigation fixed weir, but Monitoring instruments of area increased to 900 ha. upgraded to gated weir piezometer and seismometer Water discharge and dam in 2013. Gate height is are malfunction. water level recording 1.9m. started just from 2018 June. Miral Dam Dam slope, spillway and The service area of Miral Except the gate valve other civil structures are well Dam is 1,500 hectares. It at the outlet which is maintained. decreased to 780 hectares non-functional, no but as of now it can only other hydromechanical irrigate 100 hectares devices are observed. during the dry season. Massive sedimentation that completely filled the reservoir area as well as the diversion of the water

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Name of Dam Civil Irrigation Hydro-Mechanical source to other areas in the watershed, is the major cause of this decrease in the area irrigated. Malinao(Bohol) Dam slope, spillway and Water discharge(spillway No problem other civil facilities are well and outlet) and dam water maintained. level are observed by visual contact and recorded manually. Since Irrigation area is widened, the water volume to the downstream Bayongan dam are very littel. More water can be used for irrigation if it is operated properly. Now at the time of flooding intake gate is closed because of clogging of intake screen. Bayongan(Bohol) Dam slope, spillway and Planned irrigation area is No problem other civil facilities are well 4,170 ha but it is only maintained. 3,063 ha now. It was planned to supply water from Bayongan dam to the downstream Capayas dam, but water is short and not reach to Bayongan dam. Conversely, there are cases where wastewater of Capayas dam is distributed to the irrigation area of Bayongan. Capayas Dam The vegitaion are growing on The planned irrigation area No problem (Bohol) the dam slopes. of 750 ha is irrigated as planned, and water discharge and dam water level are observed by visual contact and recorded manually. Source: The Study Team

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Table 3.14 Main Findings of Site Reconnaissance (Social and Environmental)

Name of Dam Social Environmental Ambuklao Dam • The people resides on watershed area and • The 1990 earthquake was being blamed by did slash & burn for agricultural the people for the massive soil erosion production; which caused heavy sedimentation on • Gov’t have provided/constructed road on Agno River. watershed area thus, opening to more • As observed heavy sedimentation is caused populace to use it for agricultural by the multiple land use of the watershed. (specifically vegetable production) • Land conversion of watershed was production. approved by the government. Binga Dam • Displaced IPs(who used to till the land • The 1990 earthquake was being blamed by submerged by the dam) known as Ibaloi the people for the massive soil erosion was resettled and provided with which caused heavy sedimentation on livelihood, health center, school building, Agno River. and other social services. • As observed heavy sedimentation is caused • Some Ibaloi’s resettled in the watershed by the multiple land use of the watershed. and have cultivated for agricultural • Mining in the upstream of the dam production. • In case of implementing sediment flushing and bypassing, environment impacts in the downstream stretch shall be considered, particularly for the San Roque Dam. Pulangi Dam • NPC has been providing community • Inhabited and multiple land use watershed; social responsibility/ies to inhabitants in • NPC is currently contracting dredging the watershed; (NPC called it “surgical” in nature) due to • NPC forged MOA with DENR re: agro- heavy sedimentation; forestry and reforestation; • There are People’s Organizations (POs) within the watershed; • They have IEC re: watershed management; and • NPC is providing P19,000/ha/family for agro-forestry. Magat Dam • NPC has community and social • The 1990 earthquake was being blamed by responsibility/ies (CSR) projects and the people for the massive soil erosion programs for watershed management; which caused heavy sedimentation on • MARIIS is a member of PDRRMC and Magat RDRRMC • As observed heavy sedimentation is caused by the multiple land use of the watershed; • Multiple use of the dam (irrigation, fish production, tourism & recreation, hydropower, water supply and mode of transportation); Hence, it is suggested to have water allocation to include low-flow so as to sustain ecology in the downstream of the river system; • There is a fault line downstream of the spillway

Lupao Dam • There are existing Irrigators’ Associations • Heavy sedimentation about 7 meters high (IAs) being served by Lupao Dam. which according to NIA officials - this • Watershed has no inhabitants but this has has been triggered by the 1990 earthquake; been deforested through slash and burn • NIA has been finding a solution/s to and turn the land into an agricultural minimize deposition of heavy sediments production area and charcoal making is through construction of sabo dams, also rampant; • As observed, heavy sedimentation is caused • MOA between NIA and DENR re: by deforestation and there is also small

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Name of Dam Social Environmental watershed management. mining upstream of the dam(but this was • NIA spent P12M for watershed already stopped by the DENR) restoration and management • Also, the watershed was planted with gmelina trees where this caused the soil surface to dry up, hence, susceptible and becoming so fragile to heavy rain which in turn resulted to erosion and eventual sediment loading on river course. Tanguilad • There are Communal Irrigators’ • Watershed has multiple land use such as Association (IAs) being served by residential, agricultural production, agro- Tangilad Dam; forestry, piggery farm, etc. • Presence of inhabitants in the watershed; • Heavy siltation/sedimentation at the • Local tourists are coming to the dam use upstream and downstream of the dam site. impounded water of the dam and running • Presence of volcano (Mt. Natib) where water from spillway for swimming and manifested of huge volcanic rock at the recreation. damsite. • There was a landslide at the left side of the spillway Miral Dam • According to Engr. Reuben O. Paden, the • The watershed is part of the declared Federation of Irrigators’ Association of (Republic Act (RA) No. 9237) Mt. Apo the Province of Davao del Sur already protected area under the category as the Mt. wrote President Duterte regarding the Apo Natural Park illegal tapping of water of upstream • Denuded watershed due to massive farmers who are planting vegetable and agricultural production of various other crops but this issue is still agricultural crops unresolved up to the present time; • Presence of fault line at the left side of the • According to NIA, water for irrigation is of the spillway; in sufficient to irrigate service area and • There is heavy sedimentation at the has been raised to numerous meeting and reservoir; negotiations but still unresolved as • The government of Davao del Sur according to farmers (members of IAs) constructed road network within the illegal users of water are supported by watershed area; politicians in terms of funding • As observed, there is no proper disposal of agricultural production activities. solid waste. • Indigenous Peoples (IPs) are also controlling water source upstream. Malinao/ • There is a MOA between the NIA Reg 7, • Accumulation of Silt/sedimentation the at Bayongan/ LGU, and Federation of Irrigators’ reservoir due to deforestation and/or Capayas(Bohol) Associations “mandated to develop, watershed denudation; Because of this, the operate and maintain” the Bohol following reforestation projects is being Integrated Irrigation Systems comprising undertaken: Malinao, Bayongan and Capayas Dams to 1) Centennial Forest located upstream of improve the socio-economic status of Malinao Dam. It covers 100 has manage farmers; Also, to implement AWD & maintain by LGU. This is established (alternative wetting/drying) Technology by the Civil Service Commission. of water delivery in the Every year, the LGU allocate P200,000; downstream/upstream of the irrigation 2) Natural forest which covers 890 system in rotation of irrigation water and hectares; water saving techniques; and this includes 3) Plantation Forest covers 1,312.25 participation of all water users in hectares; reforestation of the watershed areas. 4) Agro-forestry has 382 hectares and • There are forty (40) barangays covered by currently being funded through the irrigation systems. INREM. • Every first week of June is their tree planting schedule Source: The Study Team

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Table 3.15 Main Findings of Site Reconnaissance (Adaptation of Japanese Technology)

Name of Dam Adaptation of Japanese Technology Ambuklao Dam In case of dam heightening, advance construction technology which enable to implement works without lowering reservoir water level can be considered. For study and investigation for countermeasures of reservoir sedimentation, a comprehensive study adopted Japanese technology is also recommended to be implemented. Binga Dam Same as above. Pulangi Dam In the case of improvement for spillway and to replace the gate, it will be proposed to apply the maintenance free and high strength stainless steel gate by Japanese technology. Magat Dam In the case of improvement for spillway and to replace the gate, it will be proposed to apply the maintenance free and high strength stainless steel gate by Japanese technology. Lupao Dam Packaging development of dam restoration and upgrading adapting Japanese technology can be considered. Tanguilad Packaging development of dam restoration and upgrading adapting Japanese technology can be considered. Miral Dam Packaging development of dam restoration and upgrading adapting Japanese technology can be considered. Malinao(Bohol) NIA is planning of elevation up by rubber dam, and it is available to propose Bayongan (Bohol) Japanese rubber dam. Capayas (Bohol) For study and investigation for countermeasures of reservoir sedimentation, a comprehensive study adopted Japanese technology is also recommended to be implemented. For construction method of Japanese technology which make possible to shorten the water stopping period can be considered. In case of development of mini hydropower, advance construction technology which enable to implement works without disturbing the irrigation water supply can be considered. Source: The Study Team

Table 3.16 Main Findings of Site Reconnaissance (Possibility of Financial of Japanese ODA)

Name of Dam Possibility of Financial of Japanese ODA Ambuklao Dam Already Norwegian company studied. IPPA is a private foreign company (SNAP). Binga Dam Same as above Pulangi Dam Already private company (Philippine) offers the upgrading. Located in Mindanao (JMOFA Security Level 2) Magat Dam Magat dam power component is owned and operated by SN Aboitiz, therefore it might be difficult to apply ODA. However, Baligatan hydropower plant (6MW), which locates upstream of MARIIS can be applicable because it is owned and operated by NIA-MARIIS. Lupao Dam NIA SRIP Dam. The project scale is small for Japanese ODA. Tanguilad NIA SRIP Dam The project scale is small for Japanese ODA. Miral Dam NIA SRIP Dam. The project scale is small for Japanese ODA. Located in Mindanao (JMOFA Security Level 2) Malinao(Bohol) JICA funded for construction. It is considered effective to sustain the project function by dam restoration and upgrading. Bayongan(Bohol) Same as above Capayas (Bohol) Same as above Source: The Study Team

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Second Screening of the Short-listed Projects and Selection of Priority Project

1) Criteria of Second Screening

Second screening is carried out for the short-listed projects to select a priority project subject to the pre-feasibility study. The criteria of the 2nd screening will be determined through discussion with the counterpart.

i. reservoir sedimentation condition, ii. safety of the dam body, iii. conditions of operation and maintenance, iv. socio-environmental issues, v. adaptability of Japanese advanced technology, vi. economic viability (preliminary), vii. possibility of financial aid from JICA, ODA loan and JBIC loan, and viii. reduction efficiency of energy sourced CO2, etc. Each criteria is given weights in the evaluation. A list is prepared by sorting in the order of the prioritization. The highest prioritized dam is selected for the pre-feasibility study to be conducted in the next stage.

At this time, TOR and work schedule are reviewed to study approach and methodology for solution of the issue of the selected dam.

2) Weighting of Criteria for 2nd Screening

i) reservoir sedimentation condition, Sedimentation Minor Medium Serious None Fair Condition problem problem problem Point 1 2 3 4 5 ii) safety of the dam body Minor Medium Serious Dam Safety None Fair problem problem problem Point 1 2 3 4 5 iii) conditions of operation and maintenance Condition of Poor Not good Fair Good Very good O&M Point 1 2 3 4 5 iv) socio-environmental issues, Socio Serious Minor -environmental Fair None Better problem problem Issues Point 1 2 3 4 5 v) adaptability of Japanese advanced technology, Japanese More None Less Fair Applicable Technology Applicable Point 1 2 3 4 5

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vi) economic viability (preliminary) Economic Lower Low Fair High Higher Viability Point 1 2 3 4 5 vii) Possibility of financial aid from JICA, ODA loan and JBIC loan Applicable Applicable Financial Applicable None Possible (2 Step loan) Yen Loan Scheme IPPF (STEP) Point 1 2 3 4 5 viii) Reduction efficiency of energy sourced CO2, etc. Reduction Lower Low Fair High Higher Effect of CO2 Point 1 2 3 4 5

3) Result of 2nd Screening

The result of second screening is shown below:

Table 3.17 Result of Second Screening (tentative)

No. Name of Dam Total technology ODA loan and JBIC loan ii. Safety of the dam body ii. of Safety Irrigation, Hydro-Mechanical)Irrigation, iii. Conditions O&M(Civil, of issuesiv. Socio-environmental viii. Reduction CO2 efficiency of i.Reservoir sedimentationcondition vi. Economic viability(preliminary), vii. Possibility financial of JICA of v. Japanese Adaptability of advanced

NPC-01 Ambukulao Dam 4 4 5 3 3 4 2 5 30

NPC-02 Binga Dam 5 4 5 3 3 4 2 5 31

NPC-12 Pulangi Dam 4 2 3 3 3 4 1 4 24

NIA-M01 Magat Dam 2 3 5 3 3 4 3 4 27

NIA-S02 Lupao Dam 5 4 2 5 5 3 3 3 30

NIA-S03 Tanguilad 3 3 3 4 3 3 3 3 25

NIA-S11 Miral Dam 5 4 2 4 3 3 3 3 27

NIA-I04 Malinao(Bohol) 4 3 5 3 4 4 4 4 31

NIA-I05 Bayongan(Bohol) ------

NIA-I06 Capayas(Bohol) ------

Source: The Study Team

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4) Result of Selection of the Project for Pre-F/S

As the result of the second screening, following projects were selected as the candidates for the pre-feasibility study. Out of these candidates, taking into consideration that Ambuklao/Binga Dams are belong under private company operation, and the dams in Bohol have been constructed under Japanese ODA projects, ”Restoration and Upgrading Irrigation Dams in Bohol ” was selected as the target project for the pre-feasibility study.

◆The selected Project for pre-F/S

i) ”Restoration and Upgrading Irrigation Dams in Bohol ”

◆2nd priority

ii) ”Restoration and Upgrading Binga Dam”

iii) ”Restoration and Upgrading Lupao Dam”

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3.4.2 Basic Design of the Selected Project

The previous section selected Bohol Irrigation Project as a potential project for implementation. This section discusses the Bohol Irrigation Project in detail.

Project Components and Dimensions

The following three dams were constructed for Bohol Irrigation Project.

Dam Name Catchment Area Reservoir Volume Max. Irrigation (km2) (MCM) Water (m3/s) i) Malinao Dam 138.8 6.0 11.8 ii) Bayongan Dam 11.2 34.6 6.48 iii) Capayas Dam 14.6 4.1 2.23 The dams irrigate the farm land through irrigation canals. The dams are connected with each other as shown in Figure 3.21. Extra irrigation water yielded by Malinao Dam having the bigger catchment area is dropped down to Bayongan Dam through the diversion chute with the capacity of 11.8 m3/s.

Record of Reservoir Operation

The Study Team obtained the following operation record data from NIA.

Table 3.18 Collected Data of Dam Operation Records Facility Name (Data duration) Record Item Note Reservoir water level Recorded data Calculating the discharge by the recorded Water outlet discharge overflowing depth at the outlet Malinao Dam (2005 - 2018) Calculating the discharge by the recorded Spillway discharge overflowing depth at the spillway Calculating the inflow by the recorded Reservoir inflow reservoir water level (volume conversion) Calculating the discharge by the recorded Diversion chute (2008 - 2017) Discharge overflowing depth at the weir Reservoir water level Recorded data Calculating the discharge by the recorded Water outlet discharge overflowing depth at the weir Bayongan Dam (2008 - 2017) Calculating the discharge by the recorded Spillway discharge overflowing depth at the spillway Calculating the inflow by the recorded Reservoir inflow reservoir water level (volume conversion) Source: The Study Team

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0 . 28 . 2 nos s / 3 m 23 appoximate EL . ； 2 ； φ = 0 . 6 m× Water Level Level Water Gate MCM 4 Main Canal Main Design Discarage . Sluice 3 . MCM 1 . ； 4 2 ； km 6 . DAM 14 ； 5 0 . . 36 30 LWL CAPAYAS NHWL s 0 . / 3 40 . m EL 48 Catchment Area Area Catchment Gross Reservior Volume Reservior Gross Effective Reservior Volume . ； 6 W ； ｋ φ = 1 . 5 m 226 330 s ； km / 1 3 . m Mwh Gate 11 5 Water Level Level Water ; . 2.5 3 ； 630 ｍ 625 ; 2 . MCM 12 16 Length Main Canal Main Design Discarage ; . MCM Jetflow 6 . 25 5 34 . ；

2 55 . ； DAM km EL s 2 . / ｍ 3 8 . Annual generation Annual BayonganHydraulic Power Station Maxium Discarage Maxium Power Generation Power Maxium Maxium Head 11 m ； 8 72 . 0 11 . 80 . ； 0 . 52 41 127 D BAYONGAN . - EL ； NHWL LWL s / apporoximate 3 ； m Catchment Area Area Catchment Effective Reservior Volume Gross Reservior Volume Reservior Gross 8 . 11 ； Height Design Discarage

DiversionShute Water Level Level Water km 5 . 40 . 18 ) φ = 2 . 0 m ； 145 . EL ； Design Discharge Length Valve estimate W Main Canal Main

( ｋ 0 . 289 55 400 . s ； W / EL 3 ｋ ； m Butterfly Level Water Mwh 5 . 650 , 7 5.0 847 1,038 1 ； MCM 988 s ; ； m 0 . / MCM 3 3 . 5 0 4 . 7 m . ; Mwh 6 0 ；

. 2 2.0 3 Water Level Level Water 156 ； . 669 ； m 4,491 , km 8 3 8 . ; . EL DAM 72 138 0 . ； 0 . Annual generation Annual Malinao Hydraulic Power Station Power Hydraulic Malinao Maxium Discarage Maxium Power Generation Power Maxium Maxium Head 152 146 MALINAO LWL NHWL Maxium Head Generation Power Maxium Maxium Discarage

Diversion Shute Hydraulic PowerStation Hydraulic Diversion Shute Annual generation Annual Effective Reservior Volume Catchment Area Area Catchment Volume Reservior Gross SpecificationsPower of StationOperation: ※

Source: The Study Team

Figure 3.21 Project Outline

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The water volume balance in the reservoir is expressed in the following equation.

（Qi - Qout - Qspill）・ ⊿ T＝⊿V

3 Where, Qc; Inflow (m /s)

3 Qout; Water outlet discharge (m /s)

3 Qspill; Spillway discharge (m /s)

⊿T; Unit time（sec）

⊿V; Reservoir water volume change (m3)

The reservoir inflow is calculated in the following equation.

Qi＝⊿V／⊿T+Qout＋Qspill

When Qi is calculated negative (Qi<0), Qi is set at zero (Qi=0), and Qout is recalculated.

The recorded data is in deficit, the reservoir water level is assumed to be same as that in the previous day and reservoir inflow is assumed to be same as outlet discharge (Qc = Qspill).

The monthly Reservoir water level, Water outlet discharge, Spillway discharge, Reservoir inflow are shown in the Figure 3.22 below.

Malinao Bayongan 6,000,000 12 35,000,000 3.5 5,000,000 10 30,000,000 3 25,000,000 2.5 4,000,000 8 20,000,000 2 3,000,000 6

(cu.m) (cu.m) 15,000,000 1.5 (cu.m/s) (cu.m/s) 2,000,000 4 10,000,000 1 1,000,000 2 5,000,000 0.5 0 0 0 0 Jan. Feb. Mar. Apr May Jun Jul Aug Sep Oct Nov Dec Jan. Feb. Mar. Apr May Jun Jul Aug Sep Oct Nov Dec Inflow Intake outflow Spillway Outflow Reservior volume Inflow Intake outflow Spillway Outflow Reservior volume

Discharge from Malinao Shute to Bayongan Spillway Outflow 2 12,000,000 1.8 10,000,000 1.6 1.4 8,000,000 1.2 1 6,000,000 (cu.m) 0.8 (cu.m) 4,000,000 0.6 0.4 2,000,000 0.2 0 0 Jan. Feb. Mar. Apr May Jun Jul Aug Sep Oct Nov Dec Jan. Feb. Mar. Apr May Jun Jul Aug Sep Oct Nov Dec Bayongan Shute Malinao Bayongan

Source: The Study Team (The Study Team produced based on NIA Data)

Figure 3.22 Hydrological and Operation Data of Bohol Project

Table 3.19 shows the recorded spill out discharge at Malinao Dam and Bayongan Dam. The annual spill out volume is 32 mil. m3 at Malinao Dam and 22 mil. m3 at Bayongan Dam. The spillout discharge needs be reduced to utilize water resources effectively.

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Table 3.19 Recorded Spillout Discharge

Unit : Mil. m3 Dam Name Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total

Malinao 5.25 1.69 0.77 0.04 0.06 1.77 4.89 0.46 4.01 11.15 1.19 1.43 32.72

Bayongan 3.86 1.92 0.94 1.44 0.73 1.18 1.96 0.97 1.24 3.57 2.93 1.36 22.11

Source: The Study Team (The Study Team produced based on NIA Data)

Improvement Plan of Malinao Dam

NIA plans to increase the reservoir volume by installing rubber gate at the overflow weir of the spillway. The reservoir water level can be raised at 2 m height. As well, emergency spillway will be provided additionally. The national consultant completed the design work, and bidding exercise for the construction will be implemented soon.

Source: NIA Region VII

Figure 3.23 Spillway Improvement Plan at Malinao Dam

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This plan will change the designed reservoir water level and dam operation plan. The structural stability of dam body and spillway structure needs to be examined carefully. The current spillway is operated freely without gate. The plan will install rubber gate, therefore emergency plan shall be established when the rubber gate dose not deflate at the necessary time. The management plan of the gate in operation and maintenance is also necessary.

(4) Improvement Plan of Bohol Irrigation Project

The following improvement is recommended for the Bohol Irrigation Project.

1) • Hydro power installation

Dam Name Installed Capacity Annual Generation Power Malinao Dam 290 kW 1,032 MWh/year Malinao Chute 1,038 kW 4,491 MWh/year Bayongan Dam 226 kW 630 MWh/year

2) • Effective use of water resource

i) Establishment of integrated operation plan of dams, irrigation water saving plan ii) Improvement Plan of Malinao Dam Spillway (NIA completed the study of the plan) iii) Establishment of sediment countermeasure at Malinao Dam The reservoir volume of Malinao Dam can be increased by 2 mil. m3 by the spillway improvement. The spill out water (non-utilized water) can be reduced by 5.6 mil. m3 annually at Malinao Dam, and can be used as irrigation water. The reservoir volume of Bayongan Dam can be increased by 6.9 mil. m3 by the spillway improvement (2 m raising).

3.4.3 Study for Hydropower Provision in Bohol Irrigation Project

Contents of Study

Hydropower facilities are not provided at Bohol Irrigation Project. This section discusses technical study of the hydropower provision at Malinao Dam, Diversion Chute and Bayongan Dam. This section studies the following items, i) reviewing the record of reservoir operation (reservoir water level, reservoir inflow, reservoir outflow), ii) maximum power output, annual generation power, construction cost depending on turbine discharge, iii) economical project scale based on indicator of kWh construction cost.

Hydropower Scheme

1) Setting Operation Mode

Four operation patterns, A, B, C, and D are established for the simulation of power generation, and are discussed below.

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Table 3.20 Operation Patterns for Power Generation Operation Pattern Reservoir Volume Outflow Pattern A 6.0MCM (Current) Current Operation Pattern B 6.0MCM (Current) Minimum discharge1.0m3/s Pattern C 8.0MCM (Increased) Minimum discharge 1.0m3/s Pattern D 8.0MCM (Increased) Minimum discharge 2.0m3/s Source: The Study Team The current irrigation discharge depends on weather condition, farm season (irrigating or harvesting season). No irrigation water is discharged for several months because of no demand. Hydropower facility would consume the water even in no demand season for irrigation, and spillout water from the dam would be reduced.

Diversion shute Discrage(Operatin_A) 7.00

Operation Pattern A 6.00 Reservoir: 6.0MCM 5.00 Outflow ；current 4.00 Operation_A 3.00 Discharge (m3/s))

Many days with 2.00 3 outflow of 0 m3/s 1.00 0m /s

- 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 2008 2009 2010 2011 2012 Year/Month/Day2013 2014 2015 2016 2017

Diversion shute Discrage(Operation_D) 9.00

Operation Pattern D 8.00 Reservoir: 8.0 MCM 7.00 6.00 3 Outflow ； Qmin>2.0m /s 5.00

4.00 Operation_D Discharge (m3/s)) 3.00 2.0m3/s 2.00

1.00

0.00 20082008/1/1 20092009/1/1 20102010/1/1 20112011/1/1 20122012/1/1 20132013/1/1 20142014/1/1 20152015/1/1 20162016/1/1 20172017/1/1 Year/Month/Day

Source: The Study Team

Figure 3.24 Example of Dam Outflow Pattern (above: Pattern A, below: Pattern D)

The reservoir water level, full supply level, will be raised by 2.0 m height by provision of rubber gate at the overflow weir of the spillway at Malinao Dam. This water level rising increases the reservoir volume from 6.0 mil. m3 to 8.0 mil. m3. The hydropower study examines two cases, the current reservoir volume and future reservoir volume after raising at Malinao Dam.

2) Discharge, reservoir water level and outlet water level for power generation

i) Malinao Dam

The maximum discharge for hydropower is set at 11.8 m3/s to meet the maximum discharge capacity of irrigation canal. The discharge for hydropower varies depending on operation pattern as shown in Table 3.21. Reservoir water level and tail water level are set up as shown in Table 3.22.

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Table 3.21 Power Discharge at Malinao Dam

Reservoir Reservoir water volume Reservoir water volume Volume > 1.0 MCM < 1.0 MCM 3 Operation Pattern A: Current Operation 6.0 MCM Applying current operation (Qmax = 11.8 m /s) 3 3 Operation Pattern B: Qmin = 1.0 m /s When Qd=0, Qo=1.0 m /s. When Qd=0, Qo= Qi 3 3 Operation Pattern C: Qmin = 1.0 m /s 8.0 MCM When Qd>0, Qo=Qd (Qmax = 7.5 m /s) 3 3 Operation Pattern D: Qmin = 2.0 m /s (Qmax = 11.8 m /s)

Note, Qd; Outflow form the dam in current operation

Qo; Hydropower discharge

Qi; Inflow into the dam

Source: The Study Team

Table 3.22 Reservoir Water Level and Tail Water Level at Malinao Dam

Operation Pattern Reservoir Water Level (Intake Water Level) Tail Water Level Operation Pattern A Current operation record El. 145.6 m Operation Pattern B, C, D RWL is calculated depending on reservoir water volume. Source: The Study Team ii) Diversion Chute

The current operation discharge, Qdiv, at the diversion chute is applied for the hydropower

discharge at the diversion chute in the operation pattern A. Irrigation discharge, Qm, is calculated as dam outflow from Malinao dam in the current operation deducted the recorded

discharge at the diversion chute. The dam outflow from Malinao dam deducted Qm is applied for the hydropower discharge at the diversion chute in the operation pattern B, C, D. The intake water level and tail water level are respectively set at El. 127.8 m and El. 55.0 m.

Table 3.23 Power Discharge at Diversion Chute

Malinao Dam Reservoir water Reservoir water Operation Pattern Reservoir volume > 1.0 MCM volume < 1.0 MCM Volume Operation Pattern A: Current Operation Applying current operation, Qdiv 3 6.0 MCM Operation Pattern B: Qmin = 1.0 m /s 3 Qdiv=Qd-Qm (Qmax=11.8 m /s) Operation Pattern C: Qmin = 1.0 m3/s 8.0 MCM Qm=Qd - Qdiv (in current operation) Operation Pattern D: Qmin = 2.0 m3/s Source: The Study Team iii) Bayongan Dam

The maximum discharge for power generation at Bayongan dam shall be set at 6.48 m3/s and the discharge in the current operation shall be applied for the power generation discharge at Bayongan Dam. The intake water level and tail water level are shown in Table 3.24 below.

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Table 3.24 Reservoir Water Level and Tail Water Level at Bayongan Dam

Operation Pattern Power Discharge Operation Pattern A: Current Operation Dam outflow discharge in current operation 3 Operation Pattern B, C, D (Qmax=6.48 m /s) Source: The Study Team

Table 3.25 Power Discharge at Bayongan Dam

Reservoir Water Level (Intake Water Level) Tail Water Level Operation Pattern A Current operation record Operation Pattern B, C, D RWL is calculated depending on reservoir water El. 40.0 m volume. Source: The Study Team

3) Simulation Results of Power Hydrology

Power hydrology, power discharge and reservoir water level, was computed for power generation simulation, based on the operation patterns discussed above.

Outflow discharge from Malinao Dam and Diversion Chute, and the reservoir operation chart are shown in Appendix. The calculation results of Operation Patterns A, B, C and D are shown in Appendix 7.

4) Preparation for Power Generation Simulation

i) Type of Generating Equipment and Generating Efficiency

Type of Turbine and Turbine Efficiency

Type of turbine can be selected from Figure 3.25 below. Maximum discharge can be obtained to minimize the kWh cost as discussed in the later section. Selection results of the type of turbine are shown in Table 3.26 below.

5000kW 1000 1000kW

500kW

vertical Kaprun vertical shaft Francis 100 100kW Diversion shute horizontal shaft Francis vartical shaft Pelton 50kW horizontal shaft Pelton S-shape tubular

Head H(m) vertical tubular Bayongan cross- flow

10 Malinao Turgo impluse conduit valve 5000kW Malinao Diversion shute Bayongan 1000kW

50kW 100kW 500kW 1 0.1 1 10 100 Discharge Q(m3/s)

Figure 3.25 Selection Chart of Turbine Type

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Table 3.26 Selected Turbine Type

Maximum Maximum Maximum Discharge Water Head Power Output Turbine Type Q (m3/s) H (m) P (kW) Malinao 5.0 7.31 267 Tubular Diversion Chute 2.0 72.8 1,038 Horizontal Francis Bayongan 2.5 12.17 231 Tubular Source: The Study Team Turbine efficiency is dependable on the ratio of the power discharge, Q, to the maximum

discharge, Qmax, as shown in Figure 3.26 below.

Turbine efficiency 1.00 0.95 0.90 0.85 0.80 0.75 0.70 0.65

Turbine efficiency 0.60 0.55 0.50 0.0 0.2 0.4 0.6 0.8 1.0

Discharage ratio(Q/Qmax)

Malinao Bayongan Diversion Shute

Source: The Study Team

Figure 3.26 Turbine Efficiency

Generator Efficiency

The elements of the generator are shown in Table 3.27 below. Generator efficiency is

dependable on the ratio of the load (Q x He) to the maximum load (Qmax x Hemax), as shown in Figure 3.27 below.

Table 3.27 Number of Pole and Relative Velocity of Generator

Upper Limit Rotation Relative Effective Maximum Turbine Relative Number Speed Velocity Head Generation Type Velocity ns of Pole n ns He(m) kW m-kW r/min m-kW Malinao 6.63 Tubra 409 978.1 16 450 856 Diversion Chute 67.19 Francis 1,659 276.6 6 1,200 254 Bayongan 11.65 Tubra 336 809.5 10 720 613 Source: The Study Team

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0.960

0.940

0.920

0.900

0.880

Malinao Generator efficiency0.860 Diversion 0.840 Shute Bayongan 0.820 0 0.2 0.4 0.6 0.8 1 Q*He/Qmax*Hemax

Source: The Study Team

Figure 3.27 Generator Efficiency

ii) Pressure Pipeline

Pressure pipeline will be branched from the existing intake pipe. The pipe diameter shall be less than the existing intake pipe, and be determined based on flow velocity.

Table 3.28 Maximum Flow Velocity in Penstock

Total Head (m) 2 - 7 7 - 15 15 - 30 30 - 100 100 - 200 Velocity in Penstock (m/s) 1.0 1.5 2.0 3.0 4.0

Table 3.29 Designed Pipe Diameter

Existing Selected Maximum Flow Design Calculated Pipe Pipe Penstock Velocity Name discharge Diameter D Diameter Diameter Velocity v v (m3/s) (m) Do D (m/s) (m/s) (m) (m) Malinao 5.0 1.0 2.52 2.00 2.00 1.59 Diversion Chute 2.0 3.0 0.92 - 1.00 2.55 Bayongan 2.5 1.5 1.46 1.50 1.50 1.42

5) iii) Effective Water Head

Effective water head is calculated in the following equation.

He = (H - HTWL) - HL

where, He; Effective water head

H; Intake water level (Reservoir water level)

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HTWL; Tail water level

HL; Friction head loss

2 1/3 2 HL＝k・124.5・n ／D ・Lp・（ ｖ /2g）

where, k; Coefficient (1.5)

n; Roughness coefficient

D; Diameter of steel pipe

Lp; Length of pipe

v; Flow velocity

g; Gravity acceleration

Conditions for Study for Optimum Scale

1) Operation Pattern

The said four (4) operation patters for hydropower generation are adopted.

2) Maximum power discharge

For maximum power discharge, 6 to 7 cases are established for the simulation of power generation; 3.0 m3/s – 8.0m3/s for Malinao, 1.5 m3/s – 4.5m3/s for Diversion Chute, and 1.5 m3/s – 4.0m3/s for Bayongan,

3) Calculation for power generation

Power output (kW) and annual generating energy (MWh) are calculated based on the daily simulation of hydropower generation.

4) Rough Estimation of Construction Cost

Construction cost is roughly estimated based on technical reference book, "Guidebook for Medium/Small Scale Hydropower" by New Energy Foundation, Japan. The guidebook provides the regression formula to estimate the costs based on variable parameters such as power discharge, effective head, maximum power output in the existing projects.

The regression formulas of power house, intake structure, head tank, pressure pipeline, outlet structure, machine equipment, electric equipment are shown in Appendix 8.

5) Criteria for selection of optimum scale

The optimum project scale or the maximum power discharge is selected to minimize the kWh cost, construction cost (C) divided by annual generation power (B).

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Power Simulation Results and Unit Costs

Annual generation power is simulated during the operation period, Malinao power station from 2005 to 2017, Diversion chute power station and Bayongan power station from 2008 to 2017. Construction cost is estimated applying statistical regression formula.

The results of annual generation power and construction cost are shown in Appendix 7.

1) Malinao Power Station

The calculation results are shown in Table 3.30.

The acceptable unit cost is expected less than 100 PHP/kWh. Malinao hydropower station is not attractive because of the high construction cost.

Table 3.30 Calculation Results at Malinao Power Station (1)

Item Operation_A Operation_B Operation_C Operation_D Malinao Reservoir Volume MCM 6.0 6.0 8.0 8.0 Minimum Discharge m3/s 0.0 1.0 1.0 2.0 Power Discharge to m3/s 5.0 5.0 5.0 5.0 minimize kWh cost Maximum Power Output kW 267 246 290 289 Annual Generating Energy MWh 916 837 1,032 847 Construction Cost 106PHP 202 199 207 207 Construction Cost per kWh PHP/kWh 221 237 201 244 Selection 〇 〇 Source: The Study Team

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Table 3.31 Calculation Results at Malinao Power Station (2)

Malinao Max.Generation Output Pmax kw 428 374 321 267 214 160 Max. Discharge Qmax m3/s 8.00 7.00 6.00 5.00 4.00 3.00 Average Discharage Qave m3/s 3.41 3.27 3.04 2.73 2.33 1.82 Effective Head He ｍ 7.19 7.19 7.19 7.19 7.19 7.19 Annual generation ΣP Mwh 1,097 1,072 1,012 916 789 620 Operation-A (Malinao Architecture(Power house ) 6 5 5 4 3 3 V=6.0MCM,Qmin=0m3/s) Civil work 48 46 44 42 40 38 Electrical equipment 164 149 133 116 99 80 106PHP Cost for temporary facilities 22 20 18 16 14 12 General expense 31 29 26 23 20 17 Construction cost(total) 271 249 226 202 177 150 Unit construction cost PHP/kwh 247 232 223 221 225 242

Max.Generation Output Pmax kw 394 345 296 246 197 148 Max. discharge Qmax m3/s 8.00 7.00 6.00 5.00 4.00 3.00 Average discharage Qave m3/s 3.66 3.52 3.30 2.99 2.60 2.11 Effective head He ｍ 6.50 6.50 6.50 6.50 6.50 6.50 Annual generation ΣP Mwh 992 972 919 837 728 584 Operation-B (Malinao Architecture(Power house ) 6 5 4 4 3 2 V=6.0MCM,Qmin=1.0m3/s) Civil work 48 46 44 42 40 38 Electrical equipment 160 145 130 114 97 79 106PHP Cost for temporary facilities 21 20 18 16 14 12 General expense 31 28 26 23 20 17 Construction cost(total) 266 244 222 199 174 148 Unit construction cost PHP/kwh 268 251 241 237 239 253

Max.Generation Output Pmax kw 463 405 347 290 232 174 Max. discharge Qmax m3/s 8.00 7.00 6.00 5.00 4.00 3.00 Average discharage Qave m3/s 3.71 3.57 3.34 3.03 2.64 2.14 Effective head He ｍ 7.79 7.79 7.79 7.79 7.79 7.79 Annual generation ΣP Mwh 1,219 1,195 1,131 1,032 900 724 Operation-C (Malinao Architecture(Power house ) 6 12 11 9 8 6 V=8.0MCM,Qmin=1.0m3/s) Civil work 49 101 96 91 87 82 Electrical equipment 168 329 294 258 219 178 106PHP Cost for temporary facilities 22 44 40 36 31 27 General expense 32 63 57 51 45 38 Construction cost(total) 278 255 232 207 181 153 Unit construction cost PHP/kwh 228 214 205 201 201 212

Max.Generation Output Pmax kw 462 404 347 289 231 173 Max. discharge Qmax m3/s 8.00 7.00 6.00 5.00 4.00 3.00 Average discharage Qave m3/s 3.82 3.68 3.45 3.15 2.77 2.29 Effective head He ｍ 7.79 7.79 7.79 7.79 7.79 7.79 Annual generation ΣP Mwh 993 974 924 847 744 606 Operation-D (Malinao Architecture(Power house ) 6 6 5 4 4 3 V=8.0MCM,Qmin=2.0m3/s) Civil work 49 47 45 43 40 38 Electrical equipment 168 153 137 120 102 83 106PHP Cost for temporary facilities 22 21 19 17 15 12 General expense 32 29 27 24 21 18 Construction cost(total) 278 255 231 207 181 153 Unit construction cost PHP/kwh 280 262 251 244 243 253 Source: The Study Team

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Figure 3.28 Maximum Power Output, Annual Energy, Construction Cost and Unit Construction Cost at Malinao Power Station

Malinao_A Malinao_B 450 1,400 450 428 1,400 1,350 394 400 1,300 400 374 1,300 1,250 345 350 1,200 350 321 1,200 Pmax, 267 1,150 296 300 1,100 300 1,100 Pmax, 246 1,097 1,050 992 1,072 972

Max. power(kw) 250 1,000

Max. power(kw) 250 1,000 214 1,012 919 950 197 Annual genration (Mwh) Annual genration (Mwh) 200 900 200 900 Annual Annual 850 generation, 916 generation, 837 150 800 150 800 4.0 5.0 6.0 7.0 8.0 9.0 4.0 5.0 6.0 7.0 8.0 9.0 Discharge Q(m3/s) Discharge Q(m3/s)

Malinao_A Malinao_B 450 700 450 700 650 650 400 600 400 600 550 550 350 500

PHP) 350 500 PHP) 6 450 450 6 300 Unit cost, 221 400 300 Unit cost, 237 400 350 268 247 251 350 232 239 241 250 225 223 300 250 300 unit cost (PHP/kwh) totalcost (10 unit cost (PHP/kwh) 250 totalcost (10 271 250 200 249 200 266 226 200 244 200 150 222 177 150 150 Total cost, 202 100 174 150 Total cost, 199 100 4.0 5.0 6.0 7.0 8.0 9.0 4.0 5.0 6.0 7.0 8.0 9.0 Discharge Q(m3/s) Discharge Q(m3/s)

Operation A Operation B

Malinao_C Malinao_D 450 1,400 450 1,400 405 404 400 1,300 400 1,300 347 347 350 1,200 350 1,200 Pmax, 290 1,219 1,195 Pmax, 289 300 1,131 1,100 300 1,100 993 232 974

Max. power(kw) 250 1,000 231

Max. power(kw) 250 1,000 Annual 924 Annual genration (Mwh) Annual genration (Mwh) 200 generation, 900 200 900 Annual 900 1,032 generation, 847 150 800 150 800 4.0 5.0 6.0 7.0 8.0 9.0 4.0 5.0 6.0 7.0 8.0 9.0 Discharge Q(m3/s) Discharge Q(m3/s)

Malinao_C Malinao_D 450 700 450 700 650 650 400 600 400 600 550 550 350 500 350 500 PHP) PHP) 6 450 6 450 Unit cost, 244 300 400 300 280 400 262 350 251 350 Unit cost, 201 243 250 228 300 250 300 unit cost (PHP/kwh) totalcost (10 unit cost (PHP/kwh) 214 totalcost (10 205 250 250 201 278 278 255 200 255 200 200 232 200 231 150 181 150 181 150 Total cost, 207 100 150 Total cost, 207 100 4.0 5.0 6.0 7.0 8.0 9.0 4.0 5.0 6.0 7.0 8.0 9.0 Discharge Q(m3/s) Discharge Q(m3/s)

Operation C Operation D Source: The Study Team

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2) Diversion Chute Power Station

The calculation results are shown in Table 3.31.

The larger Maliano reservoir generates the bigger annual energy at the diversion chute power station. If the minimum discharge at the Maliano power station is set bigger, the bigger annual energy is generated at the diversion chute power station. The construction cost per kWh in Operation D is less than the acceptable unit cost of 100 PHP/kWh, and is judged as attractive project.

Table 3.32 Calculation Results at Diversion Chute Power Station (1)

Item Operation_A Operation_B Operation_C Operation_D Malinao Reservoir Volume MCM 6.0 6.0 8.0 8.0 Minimum Discharge m3/s 0.0 1.0 1.0 2.0 Power Discharge to m3/s 2.0 2.0 2.0 2.0 minimize kWh cost Maximum Power Output kW 1,038 1,038 1,038 1,038 Annual Generating Energy MWh 2,274 3,451 3,479 4,491 Construction Cost 106PHP 447 447 447 447 Construction Cost per kWh PHP/kWh 196 129 128 99 Selection 〇 〇 Source: The Study Team

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Table 3.33 Calculation Results at Diversion Chute Power Station (2)

Diversion shute Max.Generation Output Pmax kw 2,336 2,077 1,817 1,557 1,298 1,038 779 Max. Discharge Qmax m3/s 4.50 4.00 3.50 3.00 2.50 2.00 1.50 Average Discharage Qave m3/s 0.69 0.68 0.65 0.61 0.56 0.49 0.41 Effective Head He ｍ 67.20 67.20 67.20 67.20 67.20 67.20 67.20 Annual generation ΣP Mwh 2,607 2,641 2,644 2,597 2,482 2,274 1,946 Operation-A (Malinao Architecture(Power house ) 24 22 20 17 15 12 10 V=6.0MCM,Qmin=0m3/s) Civil work 248 241 233 226 218 210 201 Electrical equipment 232 215 197 178 159 137 114 106PHP Cost for temporary facilities 50 48 45 42 39 36 32 General expense 72 68 64 60 56 51 46 Construction cost(total) 627 594 560 524 486 447 404 Unit construction cost PHP/kwh 241 225 212 202 196 196 208

Max.Generation Output Pmax kw 2,336 2,077 1,817 1,557 1,298 1,038 779 Max. discharge Qmax m3/s 4.50 4.00 3.50 3.00 2.50 2.00 1.50 Average discharage Qave m3/s 1.02 1.00 0.96 0.92 0.86 0.78 0.68 Effective head He ｍ 67.20 67.20 67.20 67.20 67.20 67.20 67.20 Annual generation ΣP Mwh 3,717 3,760 3,768 3,738 3,644 3,451 3,144 Operation-B (Malinao Architecture(Power house ) 24 22 20 17 15 12 10 V=6.0MCM,Qmin=1.0m3/s) Civil work 248 241 233 226 218 210 201 Electrical equipment 232 215 197 178 159 137 114 106PHP Cost for temporary facilities 50 48 45 42 39 36 32 General expense 72 68 64 60 56 51 46 Construction cost(total) 627 594 560 524 486 447 404 Unit construction cost PHP/kwh 169 158 148 140 133 129 128

Max.Generation Output Pmax kw 2,336 2,077 1,817 1,557 1,298 1,038 779 Max. discharge Qmax m3/s 4.50 4.00 3.50 3.00 2.50 2.00 1.50 Average discharage Qave m3/s 1.04 1.01 0.97 0.93 0.87 0.79 0.69 Effective head He ｍ 67.20 67.20 67.20 67.20 67.20 67.20 67.20 Annual generation ΣP Mwh 3,749 3,793 3,801 3,770 3,675 3,479 3,171 Operation-C (Malinao Architecture(Power house ) 52 48 43 37 32 27 21 V=8.0MCM,Qmin=1.0m3/s) Civil work 534 518 501 485 468 451 433 Electrical equipment 499 462 424 384 341 295 245 106PHP Cost for temporary facilities 109 103 97 91 84 77 70 General expense 155 147 138 130 120 110 100 Construction cost(total) 627 594 560 524 486 447 404 Unit construction cost PHP/kwh 167 157 147 139 132 128 127

Max.Generation Output Pmax kw 2,336 2,077 1,817 1,557 1,298 1,038 779 Max. discharge Qmax m3/s 4.50 4.00 3.50 3.00 2.50 2.00 1.50 Average discharage Qave m3/s 1.21 1.18 1.14 1.09 1.02 0.93 0.74 Effective head He ｍ 67.20 67.20 67.20 67.20 67.20 67.20 67.20 Annual generation ΣP Mwh 4,606 4,665 4,694 4,682 4,617 4,491 3,656 Operation-D (Malinao Architecture(Power house ) 24 22 20 17 15 12 10 V=8.0MCM,Qmin=2.0m3/s) Civil work 248 241 233 226 218 210 201 Electrical equipment 232 215 197 178 159 137 114 106PHP Cost for temporary facilities 50 48 45 42 39 36 32 General expense 72 68 64 60 56 51 46 Construction cost(total) 627 594 560 524 486 447 404 Unit construction cost PHP/kwh 136 127 119 112 105 99 110 Source: The Study Team

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Figure 3.29 Maximum Power Output, Annual Energy, Construction Cost and Unit Construction Cost at Diversion Chute Power Station

Diversion shute_A Diversion shute_B 2,500 2,336 5,000 3,000 5,000 2,077 4,500 2,000 1,817 2,500 2,336 4,500 Annual 2,077 Pmax, 1,298 1,557 generation, 4,000 2,000 3,451 3,738 3,7681,817 3,760 4,000 3,644 3,717 1,500 1,557 1,038 3,500 1,500 1,298 3,500 Annual 3,144 1,000 779 generation, 3,000 Max. power(kw)

2,482 Max. power(kw) 1,000 779 3,000 Annual genration (Mwh) 500 Annual genration (Mwh) 2,500 500 2.0, 1,038 2,500 2,597 2,644 2,641 2,607

0 2,274 2,000 0 2,000 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Discharge Q(m3/s) Discharge Q(m3/s)

Diversion shute_A Diversion shute_B 400 800 400 800 750 750 350 700 350 700 627 627 650 594 650 594 Total cost, 486 300 560 600 300 560 600 PHP) PHP) 6

6 524 524 550 550 Total cost, 447 486 250 500 250 447 500 404 450 404 241 450 200 225 400 200 400 unit cost (PHP/kwh) 212 totalcost ( 10 unit cost (PHP/kwh) 208 202 totalcost ( 10 350 196 350 Unit cost, 129 150 169 300 150 300 158 Unit cost, 196 148 250 250 133 140 100 128 200 100 200 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Discharge Q(m3/s) Discharge Q(m3/s)

Operation A Operation B

Diversion shute_C Diversion shute_D 3,000 5,000 2,500 5,000 4,682 4,694 4,665 Annual 4,617 4,606 2,336 2,500 4,500 generation, 2,336 4,500 Annual 2,077 2,000 4,491 generation, 2,077 2,000 3,479 1,817 4,000 1,817 4,000 1,557 1,500 3,656 1,298 3,770 3,801 3,793 3,749 1,557 1,500 3,675 3,500 3,500 1,298 1,000

Max. power(kw) 1,000 3,171779 3,000

Max. power(kw) 3,000

Annual genration (Mwh) 779 500 2,500 500 Pmax, 1,038 Annual genration (Mwh) Pmax, 1,038 2,500

0 2,000 0 2,000 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Discharge Q(m3/s) Discharge Q(m3/s)

Diversion shute_C Diversion shute_D 400 800 400 800 750 750 350 700 350 700 627 627 650 594 650 594 560 300 560 600 300 600 PHP) PHP) 524 6 524 6 550 550 Total cost, 447 486 Total cost, 447 486 250 500 250 500 404 450 404 450 200 400 200 Unit cost, 128 400 totalcost ( 10 unit cost (PHP/kwh) unit cost (PHP/kwh) 350 totalcost ( 10 350 136 150 127 300 150 167 300 119 157 110 112 147 250 105 250 132 139 100 127 200 100 200 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Discharge Q(m3/s) Discharge Q(m3/s)

Operation C Operation D Source: The Study Team

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3) Bayongan Power Station

The calculation results are shown in Table 3.32.

Construction cost per kWh at Bayongan power station is much higher than the acceptable construction cost of 100 PHP/kWh. Bayongan power station is not attractive because of the high construction cost.

Table 3.34 Calculation Results at Bayongan Power Station (1)

Item Operation A Operation B Operation C Operation D Malinao Reservoir Volume MCM 6.0 6.0 8.0 8.0 Minimum Discharge m3/s 0.0 1.0 1.0 2.0 Power Discharge to m3/s 2.5 2.5 2.5 2.5 minimize kWh cost Maximum Power Output kW 231 229 229 226 Annual Generating Energy MWh 502 511 511 630 Construction Cost 106PHP 155 154 154 153 Construction Cost per kWh PHP/kWh 308 302 302 243 Selection 〇 〇 Source: The Study Team

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Table 3.35 Calculation Results at Bayongan Power Station (2)

Bayongan Max.Generation Output Pmax kw 370 324 277 231 185 139 Max. Discharge Qmax m3/s 4.00 3.50 3.00 2.50 2.00 1.50 Average Discharage Qave m3/s 1.31 1.24 1.14 1.00 0.85 0.67 Effective Head He ｍ 12.46 12.46 12.46 12.46 12.46 12.46 Annual generation ΣP Mwh 600 585 553 502 435 351 Operation-A (Malinao Architecture(Power house ) 5 5 4 4 3 2 V=6.0MCM,Qmin=0m3/s) Civil work 39 38 36 35 33 32 Electrical equipment 121 110 98 86 73 59 106PHP Cost for temporary facilities 16 15 14 12 11 9 General expense 24 22 20 18 16 13 Construction cost(total) 205 189 172 155 136 116 Unit construction cost PHP/kwh 342 323 311 308 313 331

Max.Generation Output Pmax kw 366 320 274 229 183 137 Max. discharge Qmax m3/s 4.00 3.50 3.00 2.50 2.00 1.50 Average discharage Qave m3/s 1.31 1.24 1.14 1.00 0.85 0.67 Effective head He ｍ 12.30 12.30 12.30 12.30 12.30 12.30 Annual generation ΣP Mwh 609 595 563 511 443 358 Operation-B (Malinao Architecture(Power house ) 5 5 4 4 3 2 V=6.0MCM,Qmin=1.0m3/s) Civil work 39 38 36 35 33 32 Electrical equipment 120 109 98 86 73 59 106PHP Cost for temporary facilities 16 15 14 12 11 9 General expense 24 22 20 18 16 13 Construction cost(total) 204 188 172 154 136 116 Unit construction cost PHP/kwh 336 316 305 302 306 324

Max.Generation Output Pmax kw 366 320 274 229 183 137 Max. discharge Qmax m3/s 4.00 3.50 3.00 2.50 2.00 1.50 Average discharage Qave m3/s 1.31 1.24 1.14 1.00 0.85 0.67 Effective head He ｍ 12.30 12.30 12.30 12.30 12.30 12.30 Annual generation ΣP Mwh 609 595 563 511 443 358 Operation-C (Malinao Architecture(Power house ) 11 10 9 8 6 5 V=8.0MCM,Qmin=1.0m3/s) Civil work 84 81 78 75 72 69 Electrical equipment 259 235 210 184 156 127 106PHP Cost for temporary facilities 35 33 30 27 23 20 General expense 51 47 42 38 34 29 Construction cost(total) 204 188 172 154 136 116 Unit construction cost PHP/kwh 336 316 305 302 306 324

Max.Generation Output Pmax kw 361 316 271 226 181 136 Max. discharge Qmax m3/s 4.00 3.50 3.00 2.50 2.00 1.50 Average discharage Qave m3/s 1.31 1.24 1.14 1.00 0.85 0.67 Effective head He ｍ 12.30 12.30 12.30 12.30 12.30 12.30 Annual generation ΣP Mwh 739 725 690 630 549 446 Operation-D (Malinao Architecture(Power house ) 5 5 4 4 3 2 V=8.0MCM,Qmin=2.0m3/s) Civil work 39 38 36 35 33 32 Electrical equipment 119 108 97 85 72 59 106PHP Cost for temporary facilities 16 15 14 12 11 9 General expense 23 22 20 18 16 13 Construction cost(total) 203 187 170 153 135 115 Unit construction cost PHP/kwh 275 258 247 243 246 259

Source: The Study Team

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Figure 3.30 Maximum Power Output, Annual Energy, Construction Cost and Unit Construction Cost at Bayongan Power Station

Bayongan_A Bayongan_B 400 1,500.0 400 1,500.0 370 366 1,400.0 1,400.0 350 1,300.0 324 350 320 1,300.0 1,200.0 1,200.0 300 277 1,100.0 300 1,100.0

PHP 274 Pmax, 229 PHP 6 Pmax, 231 1,000.0 1,000.0 6 250 900.0 250 900.0 800.0 800.0 185 200 600.0 700.0 200 183 609.0 700.0

585.4 total cost 10 594.9 total cost 10

unit cost (PHP/kwh) 553.2 562.8 600.0 unit cost (PHP/kwh) 600.0 139 434.6 137 443.0 150 Annual 500.0 150 Annual 500.0 351.0 358.2 generation, 400.0 generation, 400.0 100 501.7 300.0 100 510.8 300.0 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Discharge Q(m3/s) Discharge Q(m3/s)

Bayongan_A Bayongan_B 400 700 350 336 700 324 650 330 316 650 Unit cost, 308 342 600 306 305 600 350 331 310 323 550 550 313 311 290 500 500 PHP PHP Unit cost, 302 6 300 450 6 270 450 400 250 400 250 350 230 350 300 300

Total cost, 155 total cost 10 total cost 10 210 unit cost (PHP/kwh) unit cost (PHP/kwh) 250 205 250 Total cost, 154 188 204 200 189 190 172 172 200 200 136 136 116 150 170 116 150 150 100 150 100 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Discharge Q(m3/s) Discharge Q(m3/s)

Operation A Operation B

Bayongan_C Bayongan_D 400 1,500.0 366 400 1,500.0 1,400.0 1,400.0 350 1,300.0 350 1,300.0 320 361 1,200.0 1,200.0 300 274 1,100.0 300 1,100.0 PHP

316 PHP 6 Pmax, 229 1,000.0 Annual 1,000.0 6 generation, 250 900.0 250 271 900.0 629.5 738.9 800.0 689.7 725.3 800.0 183 200 594.9609.0 700.0 200 700.0 total cost 10 562.9 total cost 10 unit cost (PHP/kwh) unit cost (PHP/kwh) 548.9 600.0 600.0 Pmax, 226 137 443.0 445.8 181 150 Annual 500.0 150 500.0 358.2 generation, 400.0 400.0 136 100 510.9 300.0 100 300.0 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Discharge Q(m3/s) Discharge Q(m3/s)

Bayongan_C Bayongan_D 350 336 700 290 700 324 275 330 316 650 650 306 305 600 270 259 258 600 310 550 246 247 550 290 250 500 500 PHP PHP 6 6 Unit cost, 243 270 Unit cost, 302 450 230 450 250 400 400 210 230 350 350 Total cost, 154 300 300 total cost 10 210 total cost 10 unit cost (PHP/kwh) 190 Total cost, 153 unit cost (PHP/kwh) 250 203 250 188 204 187 190 172 170 200 200 170 135 136 115 170 116 150 150 150 100 150 100 0.0 1.0 2.0 3.0 4.0 5.0 0.0 1.0 2.0 3.0 4.0 5.0 Discharge Q(m3/s) Discharge Q(m3/s)

Operation C Operation D Source: The Study Team

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Development Priority

Annual generating energy, construction cost and unit costs per kWh are summarized in Table 3.33 below.

Table 3.36 Summary of Power Simulation

Operation Diversion Malinao Bayongan Total Paterｎ shute Max.Generation Output Pmax kw 267 1,038 231 1,537 Operation-A (Malinao Annual generation Mwh 916 2,274 502 3,692 V=6.0MCM,Qmin=0m Construction cost(total) 106PHP 202 447 155 804 3/s) Unit construction cost PHP/kwh 221 196 308 218 Max.Generation Output Pmax kw 246 1,038 229 1,513 Operation-B (Malinao Annual generation Mwh 837 3,451 511 4,799 V=6.0MCM,Qmin=1.0 Construction cost(total) 106PHP 199 447 154 799 m3/s) Unit construction cost PHP/kwh 237 129 302 167 Max.Generation Output Pmax kw 290 1,038 229 1,556 Operation-C (Malinao Annual generation Mwh 1,032 3,451 511 4,994 V=8.0MCM,Qmin=1.0 Construction cost(total) 106PHP 207 447 154 808 m3/s) Unit construction cost PHP/kwh 201 129 302 162 Max.Generation Output Pmax kw 289 1,038 226 1,553 Operation-D (Malinao Annual generation Mwh 847 4,491 630 5,968 V=8.0MCM,Qmin=2.0 Construction cost(total) 106PHP 207 447 153 807 m3/s) Unit construction cost PHP/kwh 244 99 243 135

Source: The Study Team Priority of hydropower development is discussed below.

Hydropower Development without Water Raising at Malinao Dam

The current reservoir volume of Malinao Dam is 6.0 mil. m3. Results of Operation A and B are the simulation results without the works to increase reservoir volume at Malinao Dam. Total unit construction cost of Operation A and B are respectively at 218 PHP/kWh and 167 PHP/kWh. Operation B, minimum outflow from Malinao Dam is set at 1.0 m3/s, is more economically attractive. Power stations at Diversion Shute, Malinao Dam and Bayongan shall be constructed in development sequence, from less unit construction cost.

Hydropower Development with Water Raising at Malinao Dam

The reservoir volume of Malinao Dam will be 8.0 mil. m3 after providing rubber gate at the spillway to raise water level. Results of Operation C and D are the simulation results after the works to increase reservoir volume at Malinao Dam. Total unit construction cost of Operation C and D are respectively at 162 PHP/kWh and 135 PHP/kWh. Operation D, minimum outflow from Malinao Dam is set at 2.0 m3/s, is more economically attractive. Power stations at Diversion Shute, Malinao Dam and Bayongan shall be constructed in development sequence, from less unit construction cost.

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Power Dimensions and Major Elements of Power Stations

Operation D creates the least unit construction Cost. Power dimensions and major elements of the power stations are listed in Table 3.34. Layout plan of Diversion Chute power station is shown in Figure 3.28.

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Table 3.37 Power Dimensions and Major Elements of Power Stations

Diversion Item Malinao Bayongan Chute Basic Plan for Hydropower Generation Maximum power output kW 289.0 1,038.0 226.0 Maximum power discharge m3/s 5.0 2.0 2.5 Maximum effective head m 7.8 67.2 12.3 Annual generation MWh 847.0 4,491.0 630.0 Head pond Width m - 50.0 - Length m - 100.0 - Depth m - 5.0 - Effective depth m - 4.0 - Effective storage m3 - 20,000 - Penstock Diameter m 2.0 1.0 1.5 Length m 25.0 293.0 25.0 Number of anchor block nos 3 14 3 Power House Width m 12.0 14.0 12.0 Length m 10.0 10.0 10.0 Height m 4.0 4.0 4.0 Tailrace Width m 3.0 3.0 3.0 Height m 2.0 2.0 2.0 Length m 30.0 18.0 30.0 Mechanical Equipment X=Q*He2/3*n1/2 - 19.67 33.06 13.32 Electric Equipment X=Pmax/He1/2 - 103.48 126.62 64.44 Source: The Study Team

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Source: The Study Team

Figure 3.31 Layout Plan of Diversion Chute Hydro Electric Power Plant

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Approximate Work Quantities

Approximate work quantities of the power stations are shown in Table 3.35 below.

Table 3.38 Approximate Work Quantities

No. Work Item Unit Malinao Diversion Chute Bayongan 1 Head Pond Excavation(soil) m3 0 31,188 0 Slope Leveling m2 0 2,975 0 Concrete Facing m3 0 1,994 0 2 Penstock 3 Excavation(soil) m 750 7,618 702 Anchor Concrete m3 55 28 41 Penstock(Material) t 8.6 43.4 5.6 Penstock(Installing) m 25 293 25 3 Power House Excavation (soil) m3 1,920.0 3,680.0 5,376.0 Foundation Concrete m3 480.0 560.0 480.0 Architecture m2 120 140 120 4 Mechanical Equipment L.S 2,343,000 5,079,000 1,311,000 PHP 5 Electrical Equipment L.S 120,336,000 137,151,000 88,533,000 PHP 6 Tailrace Water Way Excavation(soil) m3 240.0 144 240 Concrete m3 63.0 163.8 483 Source: The Study Team

Head Pond (100mx50mx4m)

Penstock φ1.0 m, L=293m

Power House 1,038kW

Source: The Study Team

Figure 3.32 Layout Image of Diversion Chute Hydro Electric Power Plant

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Approximate Construction Cost

Unit construction costs in Philippine market are applied for the cost estimation of civil works and architectural work. The costs of machine facility and electric facility are quoted from those in the guideline book.

Operation and Maintenance Cost

Operation and maintenance cost is estimated referring to the other projects. It is listed in Tables below.

Table 3.39 Annual Operation and Maintenance Cost Diversion Item Unit Malinao Bayongan Chute Direct Construction Cost Mil.Peso xxxx xxxx xxxx Annual Generation Mwh xxxx xxxx xxxx Construction Cost per kWh Peso/kWh xxxx xxxx xxxx Source: The Study Team

Table 3.40 Annual Operation and Maintenance Cost Diversion Item 単位 Malinao Bayongan Chute 1.Operation Cost Mil.Peso xxxx xxxx xxxx Repair Mil.Peso xxxx xxxx xxxx Personnel expense Mil.Peso xxxx xxxx xxxx Miscellaneous Mil.Peso xxxx xxxx xxxx 2.Administrative xxxx xxxx xxxx Mil.Peso expenses Total(1+2) Mil.Peso xxxx xxxx xxxx Operation cost power kWh Peso/kWh xxxx xxxx xxxx Source: The Study Team

Benefit for Reduction of CO2 Emission

Annual reduction volume of CO2 emission can be calculated adopting the coefficient of emission of 0.525 ton CO2/Mwh. The benefit for reduction of CO2 emission can be estimated based on CDM credit per reduction volume of 1 ton CO2 (CER)of 5US＄/CO2ton＝795 PHP.

 Annual reduction volume of CO2 emission＝ Annual effective power generation（Mwh）×coefficient of emission（0.525）  Benefit for reduction of CO2 emission＝ Reduction volume of CO2 emission x 795（PHP/ton）

Table below shows the benefit for reduction of CO2 emission of each power station:

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Table 3.41 Benefit for Reduction of CO2 Emission of Each Power Station Diversion Item Unit Malinao Bayongan Chute Annual effective power generation Mwh 630 4,491 847 Annual reduction volume of CO2 ton 330.75 2,357.78 444.68 emission Benefit for reduction of CO2 Mil.Peso 0.26 1.87 0.35 emission Source: The Study Team

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3.4.4 Consideration Concerning Operation Improvement of 3 Existing Dams

Background of the irrigation plan concerning the improvement of existing 3 dams

The planned irrigation area, the actual planting area of the Malinao Dam Irrigation scheme, Bayongan Dam Irrigation scheme Capayas Dam Irrigation scheme are as follows.

Table 3.42 Planned planting area and actual planting area of each irrigation scheme

Irrigation Designed Service area Planed planting Actual planting Rate of planting scheme irrigation area (ha)*1 area (ha)*2 area (ha) (%) (ha) Malinao 5,000 4,740 8,581 9,037 191% Bayongan 4,140 4,084 7,402 7,496 184% Capayas 1,160 1,210 1,938 1,958 176%

*1: Based on “PRINSA (Dams in the Philippines 2017)” NIA *2: NIA Region VII（planed are and actual planting area are average of 2017, 2018） Source: The Study Team Basically designed irrigation area is determined by the topographical irrigable area (land condition) by the irrigation method (gravity type, pump) and the available water source quantity (probability calculation). In the Malinao irrigation scheme large-scale agricultural land was constructed, and the area to be irrigated 5,000 ha was calculated at the time of planning, but it decreased slightly at the time of actual farmland development. Bayongan irrigation scheme and Capayas irrigation district calculated the above designed irrigation area due to constraints on the amount of water source.

Bayongan irrigation scheme and Capayas irrigation scheme calculated the above designed irrigation area due to constraints on the amount of water source. Both of these are climatically in areas where planting can be done twice a year or three times a year, and if the amount of water source permits, the planting rate can be set at 200% or more. In addition, farmers of non-irrigated areas generally request to be included in the irrigation district by canal extension. Based on the maintenance situation of the canal extension and the amount of water source in the year, the planned planting area and the actual irrigation area vary from year to year. In general, planned area is calculated based on historical experience, predicted rainfall amount, dam water storage volume etc, but depending on the actual amount of water source, the actual planting area may increase more than planned in the plenty water year. However, recently, the planned planting area itself tends to be set lower because the water source volume shortage and rainfall can not be used effectively.

Current state of irrigation plan (planning procedure and achievement) and its problems

As irrigation plan (water supply plan) Cropping Pattern is prepared with consideration the amount of dam reservoir before the dry season. Based on this, every 10th day (every half month there are cases, depending on the rainfall pattern of the irrigation scheme) irrigation water is calculated and distributed. (The effective rainfall amount is assumed to be "0")

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In the dry season the farmers depend almost on irrigation water and farming is done according to the cropping pattern because of rainfall limitation. However, in rainy season there are rainfall, so farmers can start land preparation, seedlings and plantings arbitrarily and rarely follow the cropping pattern. For this reason, the amount of distribution water for planning must be reviewed according to the actual cultivation of farmers. Generally, in actual crop cultivation by farmers, the peak amount of water will increase on land preparation and water source will be loaded. Originally it should preserve the water storage amount in the rainy season and to maximize the water storage capacity just before the dry season cultivation to secure the amount of irrigation water for the dry season, but even in the rainy season the water is used too much. Therefore, the water source amount of the dry season is insufficient.

Also, even though it is rainy season, irrigation water is distributed when there is no rainfall, but irrigation water management according to rainfall is hardly carried out. In other words, although the effective rainfall is planned as an important irrigation water source, in reality the effective use of rainfall is limited.

In other words, irrigation plan can be formulated theoretically, but in order to make sure this as a feasible plan, it is preferable to establish an irrigation water management system, and we have to constantly monitor weather, canal water level, farming situation (for grasping water requirement of the crop) in order to eliminate ineffective water as much as possible by comparing between necessary amount of water and actual distributing water amount.

Current status challenges of irrigation management system and improvement proposal

1) Challenge 1: Formulation of Irrigation Plan adopting Effective Rainfall

As described above, monitoring of rainfall, water level etc. is not performed sufficiently and rainfall is not used effectively.

2) Challenge 2:Accurately Observation of Discharge

Currently, in the intake of dams and from the intake, from main canal to the secondary canal, water discharge is calculated based on the water level by visual observing with staff gauge and HQ curve Calculating System. Some parts of canal are lined, and others are soil channel. In the soil channel there is a change in the shape of the cross section. So, updating of the HQ curve is recommended, but the original one of construction period is still in use. Therefore, it is not accurately observed whether canal discharge is distributed as planned.

3) Challenge 3: Suitable Gate Operation based on Rainfall/Discharge Data

The division work from the main canal to the secondary canal is often with a manual slide gate, and after the rain the gate is closed to avoid flooding. But observation data of rainfall, water flow rate are not based on observation data of the aquarium but on visual observation of canal and the field. It was just a sensuous operation. A gate keeper is placed at each gate and the discharge rate at 8 o'clock every morning is to be communicated to the management office by phone or SMS, but these records are accumulated in the office and the NIA central office as an

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archive. It has not been used for concrete irrigation water operation or next term plan. For this reason, irrigation efficiency (rate of planting) is low, and a large amount of irrigation water is wastefully discharged.

4) Challenge 4: Formulation of Appropriate Plan based on Actual Record

Also, even if rainfall is accurately observed, there is a time lag between the water source reservoir and the irrigated farmland, and there is a limit to efficient utilization of the water source. When the rain observation system is built up within the irrigation area and considering irrigation water operation incorporating effective rainfall, it is possible to reduce the amount of ineffective water for invalidation of dam reservoir. For that purpose, it is preferable to install a telemetering system that can constantly manage following items, dam reservoir volume, the amount of water discharged from the irrigation intake facility of dam, the amount of water discharged from the spillway of dam, the water discharge of each branch to the secondary canal.

5) Improvement Proposal

The monitoring system can support dam management and irrigation management by obtained data from the equipment installed in the upper dam basin, main intake facility through the cloud server via the communication line. By gathering the dam reservoir volume and the water level of each main intake facility in real time and performing the gate operation by using effective rainfall amount, it is possible to effectively utilize the water resources and to carry out appropriate farming.

The configuration of the system is as follows.

Table 3.43 Configuration of Proposed Irrigation Telemetering System Adopting the Japanese Technology

(1) Observation station Spec. ・Communication: LTE/3G/2G,WiFi, specified low power radio ・Display resolution : VGA、HD、SXGA ・Power : 20W solar or commercial power 100～240V Weather sensor Observation items: Precipitation, Temperature, Air pressure, Relative humidity, Wind direction, Wind speed, Specification: Rainfall and humidity accuracy +/- 2% Temperature measurement range: -50 to 60℃ Hydraulic type water level gauge: Accuracy: 0.1% FS · Range: Water depth 0 ~ 10 m (2)Web service for irrigation water management Providing data and service - Water level, Intake discharge, Weather, Image data - Automatic calculation of water storage and water volume based on water level, difference analysis between planned water volume and actual value - Dashboard display of the above data on target irrigation system Providing way - Cloud service of the Internet (Dedicated server construction and the maintenance by user are unnecessary)

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(1) Observation station (water level / weather meter, camera)

Site - Dam upstream area - Water intake of dam and diversion structure - In principle within the Internet service area by mobile phone line, if using outside the area use IP radio, LPWA etc. (2) The server will consider the following Domestic Japanese servers or NIA owned servers [Sensor network] Feature - Reliable sensor: High durability (10 to 15 years lifetime), high and stable accuracy - Low power consumption: Availability of solar power - Flexibility of station deployment: Selectable communication line depending on site conditions (Availability of low power radio is advantage of this system) [Cloud technology] - Low cost because of unnecessary server construction and maintenance by user - Continuous service provision of system operational environment from Japan side - Remote monitoring by internet access without dedicated device [Provision of the Web Service to customer’s needs] - Customizable observed data depending on user’s needs - Display of data (design/actual water supply, rainfall, required supply discharge etc) supports appropriate and effective farming Source: The Study Team

Implementation cost and operation maintenance cost of irrigation telemeter system in Malinao irrigation scheme and Bayongan irrigation scheme

Malinao irrigation scheme: xxxxxxxxxxxx, irrigation telemeter system shall be installed in main body of the dam (2 places, spillway and irrigation intake), upstream of the dam (3 rain gauges only), canal (18 diversion works from the main canal to the secondary canal, including diversion shut forward to Bayaongan dam).

Bayongan district: xxxxxxxxxxxx, irrigation telemeter system shall be installed in dam main body (2 places, spillway and irrigation intake) and canal (15 diversion works from the main canal to the secondary canal).

Operational maintenance cost: xxxxxxxxxxxx (Bohol irrigation district system as a whole)

Unit water volume of rice production in Bohol irrigation scheme

1) Expansion of irrigation area when 1.0 m3/sec – 2.0 m3/sec is taken as Diversion Water to Bayongan irrigation scheme

Basically, water quantity for unit is represented by design water requirement (maximum water requirement). In the Philippines, it is on average about 1.8 - 2.2 l/sec/ha. When this maximum amount of water is required, it is often the time of starting planting (at the time of land preparation). In the normal irrigation period, the water supply amount is on the order of 1.0 - 1.2 l/sec/ha on average. If there is a flow of 1.0 m3/sec it can irrigate 1,000 l/sec ÷ 1.8 l/sec /ha = 556 ha. If the maximum necessary time can be supplemented by dam reservoir volume, it can irrigate 1,000 l/sec/ ÷ 1.2 l/sec/ha = 833 ha. The design water volume of the main canal of Bohol (Malinao, Bayongan, Capayas) is 1.20 l/sec/ha because there is no definite dry season and the rainfall is large, the evaporation amount is low (Epo in the following table)*2 . However, this

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value is water amount for crop irrigation, Diversion Water Requirement for Bayongan district and Capayas district is not included. It is considered that the amount of water used during the normal irrigation period is about 0.6 - 0.8 l/sec/ha. That is, if there is a flow rate of 1.0 m3/sec, it can irrigate 1,250 ha.

2) Consideration about turning 1.0 m3/sec – 2.0 m3/secto Diversion Water to Bayongan irrigation scheme

Effective rainfall amount and inflow amount to Malinao, Bayongan dam (Rainfall Data: 1956- 2006 average, Inflow Data: 1956-1996 average)

Table 3.44 Monthly Rainfall, Evaporation and Inflow and Cropping Pattern

Item Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total/Ave. Rainfall (mm) 196 142 104 68 114 179 216 186 199 217 208 213 2,042 Eto (mm) 124 127 165 132 165 138 153 148 138 131 123 125 1,669 Average Inflow (m3/sec) Malinao Dam 6.6 4.7 2.8 1.7 1.7 3.5 4.3 3.7 4.5 5.3 6.2 5.6 4.2 Bayongan Dam 0.4 0.3 0.2 0.1 0.2 0.3 0.4 0.3 0.4 0.4 0.5 0.4 0.3 Average Inflow (MCM) Malinao Dam 18 11 7 4 5 9 11 10 12 14 17 15 133 Bayongan Dam 1.1 0.7 0.4 0.3 0.4 0.7 1.2 0.9 0.9 1.2 1.2 1.1 10.1

First (Wet) Crop

Second (Dry) Crop

Off Season

Source: The Study Team The average crop water requirement during normal irrigation period is 8 mm/day (Crop evapotranspiration: 6 mm/day + penetration amount: 2 mm/day = 8 mm/day). 240mm is required in one month (8 mm / day x 30 days = 240 mm), and from the data of Rainfall in the table above, the maximum required irrigation water is 136 mm in March (Mar: 240 mm - 104 mm = 136 mm/month). When irrigation efficiency is 60%, 0.0009 m3/sec/ha is required. ((136 mm / month) *10000/0.6 * 30 * 24 * 60 * 60). For the Malinao irrigation scheme 4,740 ha, 4.27 m3/sec irrigation water volume is necessary (0.0009 m3/sec/ha * 4740ha = 4.27 m3/sec). The inflow amount to Malinao Dam in March is 2.8 m3/sec, which is short of about 1.47 m3/sec. However, since the inflow amount in February of the previous month exceeds the irrigation water volume of 4.27 m3/sec, the effective reservoir volume of 5 MCM *1 is secured and can be used, so converting this into the flow rate 5 MCM ÷ 30 days ÷ 86,400 sec = 1.93 m3/sec, and it can cover the shortage. In fact, in March, as seen from the above Cropping Schedule, in the case of rice, it is already in the late stage of growing and the amount of water for crop is less than 8 mm/day. Moreover, in the dry season work, it is not planned to cultivate rice in the whole area, vegetables etc. are to be cultivated, and the amount of water used is considerably reduced. In other words, if farmers comply with the planning cropping pattern and properly manage the

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water supply, it can be judged that the Bohol irrigation scheme can be as planned with irrigation according to the current amount of water.

In addition, the inflow amount from mid-April to the end of June, which is the non-irrigation period, is 1.7 - 3.5 m3/sec. It is judged that 1.0 m3/sec can also be used for power generation. The issue is how to make it consistent with the maintenance period scheduled during the non- irrigation period.

Furthermore, when the Malinao Dam spillway is raised by 2 m and the full water storage capacity is set to 8.0 MCM, It can be considered to turn 2.0 m3/sec as Diversion Water (8 MCM ÷ 30 day ÷ 86,400 sec = 3.09 m3/sec).

Effect to reduce spillway outflow by improvement of the operation

Figure below shows the monthly spillway outflow from the Malinao Dam for the cases of Operation Pattern A (current operation) and Operation Pattern D. The effect of reduction of spillway outflow by improvement of the Operation Pattern D is estimated at about 6.4 MCM/year.

Spillway Outflow (Malinao) 14

12

10

8

(MM3) 6

4

2

0 Jan. Feb . Mar. Apr May Jun Jul Aug Sep Oct Nov Dec

Operation-A (6,000,000m3, 0m3/s outlow) Operation-D (8,000,000m3, 2.0m3/s outflow)

Operation-A Operation-D A-D Annual Average 33.4 27.0 6.4 (MM3)

Source: The Study Team

Figure 3.33 Effect to Reduce Spillway Outflow by Improvement of Malinao Dam Operation

Expected development effect

It was investigated that when more than a certain amount of discharge was flowed down in order to generate hydropower at the diversion chute small hydropower station located between the downstream of Malinao irrigation canal and Bayongan dam, whether irrigation water was in short supply for the Malinao irrigation operation. As the flow rate used for small hydropower generation, the minimum flow rate (1.0 m3/s or 2.0m3/s) which was suggested in the study of small hydropower development of the Bohol Island irrigation dam group was used.

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As a result of confirming the water balance based on the monthly rainfall amount, inflow amount and cropping pattern, the above power generation operation was judged applicable.

 If the cropping pattern is followed and irrigation water management managed properly, the Bohol area will be able to be irrigated as planned (over 200%) with the current amount of water source"  If it is consistent with the maintenance period planned for the non-irrigation period (April to June), the Malinao dam inflow, which is more than 1.0 m3/s in the non-irrigation period can be used for power generation  Considering the effect of raising the dam, it is also possible to turn 2.0 m3/s to the diversion chute

Based on the above, assuming the power generation operation D the benefits improving irrigation operation was considered. As an irrigation benefit, the following three benefits can be expected to increase.

1) Current irrigation area is lower than the plan, it can be restored to the plan by improvement of operation 1) By this operation, the amount of Bayongan dam inflow will increase. As the effect of using this dam reservoir the irrigation area can be increased. As this effect, the following two effects are considered. 2-1) Planting for the third term in existing Bayongan irrigation scheme during non-irrigation period 2-2) Planting for new irrigation development in Bayongan irrigation scheme during irrigation period

1) About the effect 1) Current irrigation area is lower than the plan, it can be restored to the plan by improvement of operation

It is considered the following operational improvement benefits of the Malinao, Bayongan and Capayas 3 irrigation scheme referring to the Table 3.42

(increasing irrigation area by operation improvement）= (Service area）x 200％ - (planned planting area)

Malinao: 899 (ha) =4,740 x 2 -8,581 Bayongan 766 (ha) =4,084 x 2 -7,402 Capayas 482 (ha) =1,210 x 2 -1,938 Total 2,147(ha)

2) About the effect 2) By this operation, the amount of Bayongan dam inflow will increase.

Nippon Koei Co., Ltd. 3-84 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Project Components and Technical Study Main Report Chapter 3

As the effect of using this dam reservoir the irrigation area can be increased.

The possibility of increasing the amount of Bayongan dam discharge (Bayongan irrigation scheme water supply volume) was examined. As a result of conducting a day operation simulation of Bayongan dam with reference to the past operational results, considering the scale of development based on not causing 10-year drought, it was confirmed that 15% more discharge than the current one was possible.

More detailed examination may be necessary, but from this study result, it is considered that 612 ha, which is 15% more irrigation area than existing service area (4,084 ha) can be increased in the Bayongan irrigation scheme.

3) About above 2-1) Planting for the third term in existing Bayongan irrigation scheme during non-irrigation period

Although the current irrigation plan is considered for twice planting, it is also possible for the triple planting on the water balance. And it is implemented according to the demand of farmers according to the actual amount of water source. However, the exact figures for the 3rd planting cannot be confirmed.

In this plan, it is assumed that the water source of the third planting can be secured by the increase of the water source due to NWL raising of Malinao dam and operation improvement effect.

(Irrigable service area for 3rd planting): 612ha ＊15% of existing service area (4,084ha)

4) About above 2-2) Planting for new irrigation development in Bayongan irrigation scheme during irrigation period

In implementing the new irrigation development, it is necessary to consider the constraints of the land not only the water source. As described in the report, as for the Bayongan irrigation scheme, the planned irrigated area is calculated by constraints of the amount of water source at the design period, not the constraints of the land. So, it may be necessary to confirm the details based on the current state land use map and development materials but when the water source amount is increased, it is expected that there will be some land available for new irrigation development. In the subsequent economic evaluation, we estimate the cost of this new irrigation development as expenses.

(New development area during irrigation period) : 1,224 (ha) = 612ha x 2 term Based on the above, it was assumed the following benefits by improving irrigation operation in economic evaluation.

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Table 3.45 Benefits by Improving Irrigation Operation

Increasing irrigation area Irrigation benefit remarks (ha) 1）Current irrigation area is lower than the 2,147 plan, it can be restored to the plan by improvement of operation 2-1) Planting for the third term in existing 612 Bayongan irrigation scheme during non- irrigation period 2-2) Planting for new irrigation development 1,224 Land restrictions and in Bayongan irrigation scheme during irrigation development costs irrigation period need to be considered. Source : The Study Team The following three cases are considered for economic analysis.

Case A： Increasing irrigation area 2,147ha+power generation B Case B： Increasing irrigation area 2,759ha+power generation D Case C： Increasing irrigation area 3,983ha+power generation D

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3.4.5 Study on Sediment Management

Sediment Condition

Sediment at Malinao Dam is now progressing, and it is a key issue of dam management. Excavation work to remove 15,000 m3 sediment material was carried out in 2018. The sediment material in front of the intake structure does not provide harmful effect, but trashes float in front of the intake structure and trash screen is clogged. Diver persons need to remove the trashes periodically. Floating logs are stopped by steel wire in front of the intake gate, and floating logs must be removed to the spillway.

Progress of Frequent clogging Intake Sedimentation of intake by debris

Bagon-an River Pamacsalan Wahig River River Magimitan Anibongan River River

Bagon-an River Pamacsalan River

Progress of Sedimentation

Source: The Study Team

Figure 3.34 Sediment Condition at Malinao Dam

Reservoir sediment survey was not executed at Malinao Dam. It is difficult to estimate the sediment volume and progress rate. Sediment volume is estimated below setting up the following assumptions.

i) Specific sediment load, 1 mm/yr, was applied for Bayongan Dam construction. Malinao Dam has the catchment area of 138.8 km2. The same specific sediment load is applied, the sediment volume into Malinao reservoir is estimated at 0.1388 MCM/year (=138.8 km2 x 1 mm/year).

ii) Annual flow discharge at Malinao Dam is 152.2 MCM. Brune formula below estimates soil trapping rate at 75 % approx.

C S S I E = = S 0.012 + 1.02 C in out � � � I t − in � � � �� Nippon Koei Co., Ltd. 3-87 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Project Components and Technical Study Main Report Chapter 3

Where, Et; soil trapping rate, Sin; sediment inflow volume, Sout; sediment outflow volume, C/I; reservoir rotation rate, C: reservoir volume (m3), I, annual flow discharge (m3)

The service period of Malinao Dam is 20 years after the completion in 1998. Sediment volume is estimated at 2.08 MCM (=0.1388 x 20 x 0.75). Total reservoir volume of Malinao Dam is at 6.0 MCM, the sediment rate is at about 30 % (=2.08/6.0).

Countermeasure for Sediment

Applicable countermeasures for Malinao Dam are listed below.

i) Sediment inflow countermeasure: Check dam, floating log blockage structure, catchment conservation

ii) Sediment outflow countermeasure: Sand flush gate at spillway, reservoir dewatering to accelerate sediment dry excavation, siphon sand flush

iii) Trash inflow countermeasure: Trash boom, trash removing machine

iv) Measurement method; Echo sounding, sediment measurement, sediment simulation analysis

Countermeasure Study

Check dam construction is a standard countermeasure, however, it is costly to remove or excavate periodically the sediment material at check dam. Malinao reservoir has so high rotating rate as 25.4 that the reservoir can be impound quickly after reservoir empty. Therefore, the reservoir is dewatered intentionally, and sediment can be flushed by flow tractive force. Initial cost is high to construct sand flush gate, but maintenance cost is less.

This report studies the followings. Irrigation demand is null from 15 April to 30 June. In this period, the reservoir is dewatered to low water level (LWL) of the reservoir with reservoir volume of 1 MCM, the reservoir becomes like original river morphology. Sand flush gate shall be opened at the time of small scale floods to flush out the sediment. The impacts to irrigation work by this operation are examined.

1) Reservoir Operation Record Malinao Dam

Daily reservoir water level and daily inflow discharge are shown in Figure 3.35from 2005 to 2018. Provability density function of daily reservoir water level and daily inflow discharge are shown in Figure 3.36and Figure 3.37

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Malinao Reservior(2005-2018) 154

153

152

151

150

149

148

Water Level (EL.m) 147

146

145

144 0 50 100 150 200 Daily Mean Inflow(m3/s)

Source: The Study Team

Figure 3.35 Daily reservoir water level and daily inflow discharge at Malinao Dam

Water Level Daily Mean Discharge 156 120.0 154 100.0 152 150 80.0 148 60.0 146 144 40.0 142

Water Level(EL.m) 20.0 140 Daily Mean Discharage(m3/s) Mean Daily 138 - 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.04 0.045 Probability Density Probability Density

Source: The Study Team Source: The Study Team

Figure 3.36 Provability Density Function Figure 3.37 Provability Density of Daily Reservoir Water Level Function of Daily Inflow Discharge

Average daily reservoir water level is at El. 151.2 m (El. 149.8 m - El. 152.2 m, 1σ range), average daily inflow discharge is at 5.07 m3/s. The shoulder of sediment figure may be at El. 150 m as shown in Figure 3.38 below.

Shoulder of sedimentation delta HWL 154.40 Sand Flush Gate Average Water Level EL.151NWL.2 152.00

EL 147.00

EL 137.00

Source: The Study Team

Figure 3.38 Estimated Sediment Figure

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Sand Flushing and Effects to Irrigation Operation

1) Sand Flush Gate

A part of overflow weir of the spill way will be cut and leveled down to LWL. A sand flush gate will be installed at the square notch. The gate will be closed in normal time, and the gate will be opened fully at the time of sand flushing. The section of the gate is shown in Figure 3.39 below.

Malinao

156.00

154.00 Sand Flush Gate

HWL, 152 152.00

150.00

148.00

LWL, 146 146.00

Water Level(EL.m) 144.00

142.00

140.00

138.00

136.00 1,000,000 6,000,000 0 1,000,000 2,000,000 3,000,000 4,000,000 5,000,000 6,000,000 7,000,000 Reservior Volume(m3)

Source: The Study Team

Figure 3.39 Reservoir Volume Curve and Location of Sand Flush Gate

Sill elevation of sand flush gate is elevated at El. 146.0 m (reservoir low water level), and overflow width is set at 4.0 m. Overflow discharge is calculated as in Figure 3.40 below, assuming overflow coefficient at C=1.8.

Sand Flush Gate（B=4.0m) 153.0

152.0

151.0

150.0

149.0

Waterlevel(EL.m) 148.0

147.0

146.0

145.0 0.0 20.0 40.0 60.0 80.0 100.0 120.0 Discharge (m3/s)

Source: The Study Team

Figure 3.40 Overflow Discharge at the Sand Flush Gate Nippon Koei Co., Ltd. 3-90 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Project Components and Technical Study Main Report Chapter 3

2) Sand Flush Period

The reservoir will be empty during sand flushing period. Therefore, sand flushing shall be executed during non-irrigation period.

Floods transport sediment material and floods have power to flush out sediment. Therefore, it is most effective to dewater the reservoir immediate before floods. However, it is quite difficult to forecast flood time. In this study, the reservoir dewatering will be made in non- irrigation period. The non-irrigation period in the area falls from 15 April to 30 June, for 2.5 months. The dewatering period or sand flushing time is set from 15 April to 30 May in this study, for 1.5 months, to avoid the risk of non-reservoir impounding.

3) Sand Flush Simulation

The following reservoir operation mode will be applied for sand flushing simulation.

Operation A: Reservoir volume at 6.0 MCM, minimum power discharge at 0.0m3/s

Operation D: Reservoir volume at 8.0 MCM, minimum power discharge at 2.0m3/s

Example of simulation results from 2008 to 2010 in Operation A is shown in Figure 3.41 below.

Malinao Reservior operation-D (2008-2010) Minimum Outlet Discharge 2.0m3/s Sand Flushing (Apr.15-May.30) 154 35 Irigation Irigation Irigation Irigation

152 30

Sand Flush Sand Flush Sand Flush Water Level without 150 25 Sand Flushing

Water Level 148 20 Malinao modified inflow 146 15

Discharge Q(m3/s) Malinao modified

Water Level (EL.m)) Level Water outflow 144 10 Sand Flushing

142 5

140 0 2008/1/1 2008/2/1 2008/3/1 2008/4/1 2008/5/1 2008/6/1 2008/7/1 2008/8/1 2008/9/1 2009/1/1 2009/2/1 2009/3/1 2009/4/1 2009/5/1 2009/6/1 2009/7/1 2009/8/1 2009/9/1 2010/1/1 2010/2/1 2010/3/1 2010/4/1 2010/5/1 2010/6/1 2010/7/1 2010/8/1 2010/9/1 2008/10/1 2008/11/1 2008/12/1 2009/10/1 2009/11/1 2009/12/1 2010/10/1 2010/11/1 2010/12/1 Year/Month/Day

Source: The Study Team

Figure 3.41 Example of Sand Flushing Simulation (Operation D)

The evaluation will be made as follows. If irrigation water is supplied during irrigation period without sand flushing operation, and irrigation water is not supplied with sand flushing

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operation (reservoir water level stays at LWL), then, it is judged that sand flushing operation provide harmful effects to irrigation.

4) Sand Flush Simulation Results

The simulation results are shown in Figure 3.41. Reservoir water level is generally recovered after sand flush operation even in Operation A and D, the reservoir water level from 1 July to 14 April in the irrigation period is not below the low water level. Sand flush operation does not prove harmful effects to irrigation operation.

Study on flood forecasting is recommended to avoid surely the risk of non-irrigation. Moreover, three dimension analysis of sediment flow is recommended with measurement investigation of sediment concentration, sediment particle size, sediment figure and others.

Dredging in Surrounding Area of the Intake

The construction of the sediment flushing gate is the measure to realize sustainable reservoir operation by removal of the sediment deposits within the effective storage volume above LWL.142.0. On the other hand, the sill elevation of the intake tower of the Malinao Dam is El. 137.5m that is lower than the LWL 142.0. To remove the sediment deposits in the surrounding area of the intake needs another measure.

For example, a siphon type dredging system using the effective head difference of the dam would be one of the measures for removal of the sediment deposits in the surrounding area of the intake because of advantage of reduction of operation and maintenance cost.

Source: JICA Study for Wonogiri Multipurpose Dam Reservoir Sedimentation in Indonesia (2008)

Figure 3.42 Example of Siphon Type Dredging System

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CHAPTER 4 SOCIAL AND ENVIRONMENTAL STUDY

4.1 Physical Environment

This section is the characterization of the existing natural attributes of the location of Malinao, Bayongan and Capayas dams located in the municipalities of Pilar and Ubay respectively. Ocular project site visits and observations by the Socio-Environmental Specialist and secondary data has been used to describe the physical as well as the biological and social environment of the project sites.

Water Resources/Quality

BOHOL’S central and northern lowlands have fertile grounds and abundant water supply. Its water resources is mainly use for domestic, agricultural and industrial which can be tapped from 2,224 springs, 59 rivers and 200 creeks. Surface water from 22 river basins and watersheds are impounded and distributed as potable water, for irrigation, power generation and industrial use. The province has an average rainfall varying from 1,331 mm/yr along the coastal areas to 2,006 mm/yr in the mountainous part of the island that supplies the island. The 7 major river basins considered as potential sources of water supply: • • • Wahig- • Carood River • Manaba River • Alijawan River • Ipil River (Figure 4.1).

Figure 4.1 Seven Major River Basins in Bohol Considered as Potential Sources of Water Supply Nippon Koei Co., Ltd. 4-1 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Social and Environmental Study Main Report Chapter 4

The Malinao Dam Reservoir (one of the selected sites of the project) is within the Inabanga watershed illustrated in Figure 4.2, which is the largest watershed in the island of Bohol, located (9⁰ 500N and 124⁰100E) in the central part of the Philippines. The area is about 61,000 ha, covering 16 municipalities and 98 barangays. Agricultural land constitutes more than 50 % of the watershed of which more than 60 % of the uphill land have a slope of more than 18 % susceptible to erosion. The estimated rate of land erosion is 10 m3 /ha (=1 mm) annually (PPDP 1997). This is attributed to the lack of sufficient vegetative cover in the upland areas. Improper upland farming practices and deforestation were also identified as the major causes of the problem.

Source: Bureau of Soils and Water Management (BSWM), Department of Agriculture, Region 7, Cebu City/Department of Environment and Natural Resources (DENR), Mines and GeoScience Bureau (MGB, 2008)

Figure 4.2 Inabanga Watershed and Malinao Dam Reservoir

The upper Inabanga watershed is the drainage basin of the Malinao Dam Reservoir (Figure 4.2). The two major tributaries converging into the dam are the Pamacsalan River in the eastern part and the Wahig

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River in the southwestern side. The dam was designed to serve about 5000 ha of adjoining agricultural land since 1996 and has a catchment area of about 13,800 ha including a 140-ha reservoir. The reservoir is situated at an altitude of about 140 m above mean sea level, while the highest elevation of the catchment is at 861 m (PPDP 1997).

The province has 11 watersheds. There are parts of the three major watersheds of Bohol that have been declared as protected areas under the NIPAS. The largest reserve is the Wahig-Inabanga Watershed (PP No 468, amended to PP No. 223), covering 16 municipalities with an aggregated area of 14,000 hectares. The second, and first to be proclaimed as a watershed forest reserve in Bohol, is the Loboc Watershed (PP No. 450) with an area of 10,450 hectares, part of which is inside the Rajah Sikatuna Protected Landscape (PP No. 127 as amended April 2000). The third is the Duero Watershed (PP No. 881) that covers an area of 3,620 hectares.

The rivers and river estuaries are used in many ways. They are commonly use as harbors and navigation routes, areas for aquaculture development (Inabanga River), fishing and sand quarrying areas (Abatan River) and recreation and tourism (Cambuhat River in Buenavista and the Loboc River in Loboc and Loay, Bohol). They also provide water for irrigation (Malinao Dam on the Wahig River that feeds the Bohol Irrigation Project Stage I) as well as domestic and industrial uses such as power supply (Loboc River hydro-power plant and mini hydro-power plant in ).

At present the quality of water in the province’s catchments and streams is poor and will continue to deteriorate as human development activities increase. The water resources should be managed in order to meet the growing demand for domestic, agricultural, industrial, recreational and commercial uses. At the same time proper management should prevent public health hazards associated with increasing incidence of water contamination and pollution from negligent human activities. (Source: PENRO DENR Bohol and Cebu).

Watershed Characterization and Management

The sustained operational capabilities of hydroelectric plants depend on the productive condition of the watersheds. Planning for the appropriate management of the watershed is deemed an essential part for the proposed hydropower projects because the continued generation of power depends on availability of sufficient quantity, quality and timing of water from watershed. Hence, it is imperative that proper management of the watersheds be assured and more stringent measures be adopted for its protection, development, management and rehabilitation. Development of a Comprehensive Watershed Management Plan will include the following activities:

1) Conduct of biophysical survey within the watershed area; 2) Maps (including Google Earth, if available) are required to plan out the field and survey activity; 3) Photographs of the ecosystems, landscape and important species will be taken and physical attributes of the sites will be collected; and 4) Key Informant Interview (KII) will be used primarily to provide an in-depth discussion on the condition of the watershed.

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Air Quality and Noise Level

No measurements have been made of the air quality and noise level within the three (3) project sites. However, it was observed that sources of air pollution is coming from unpaved road and due to road traffic, it puffs the dust elsewhere within the barangays. At present, there are no industry that produce noise in the barangays nor in the and/or town proper. Noise caused by the road traffic are insignificant since there are only a few vehicles that traverse the unpaved/paved road network of the project site.

4.1.2 Biological Environment

An ocular survey of flora and fauna of the proposed project site was undertaken. The survey conducted will serve as the baseline information of the existing flora and fauna of the project area prior to project implementation. This will also guide and provide guidance to the project implementers on how to implement the project with minimal environmental degradation and at the same time preserve the existing ecosystem of the area.

Bohol has a high diversity of flora and fauna found in the different ecosystems of the island such as the forests, reefs, farmlands, riparian zones along creeks and rivers, caves and cave entrances and marine areas. Data about Bohol’s terrestrial and freshwater flora and fauna is scarce except for a studies conducted in RSPL by SWCF and UBFCI. However, the biodiversity is under threat due to persistent and excessive utilization and sale of different species coupled with conversion of forests to agricultural and urban areas, monoculture farming with exotic species, farming on steep hillsides and mountains, coral reef destruction and over-fishing. In fact, several plant species noted to be abundant before are already extinct on the island while others are becoming rare and endangered.

Flora

Most of the vegetations observed were secondary growth forest trees, but what was so obvious within the identified projects environment is the vast conversion of forest into agricultural production areas. Vegetation in other parts of the reservoir/dam, are gmelina, fire trees, fruit trees and most common grasses and weeds.

The common reforestation species used in the province are gmelina (Gmelina arboria), large leaf mahogany (Swietenia macrophylla), small-leaf mahogany (Swietenia microphylla), teak (Tectona grandis), narra (Pterocarpus indicus), ipil-ipil (Leucaena leucocephala), Japanese acacia (Acacia auricularformis) and Eucalyptus (Eucalyptus spp.).

Generally the extremely diverse and dispersed vegetation in open fields could well evolve into forests without human intervention. However, most of these potential lands are within alienable and disposable areas and if it is within timberland areas they are covered under the Integrated Social Forestry Program with a Certificate of Stewardship Contract (CSC). Constant cultivation and burning inhibits forest evolution and encourages the proliferation of grasses such as cogon (Imperata cylindrical) that is

Nippon Koei Co., Ltd. 4-4 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Social and Environmental Study Main Report Chapter 4 association with other shrubs like kanding-kanding (Lantana camara). To develop systems closer to natural forests, agroforestry shall be established in these areas.

However, as observed, flora of the family Dipterocarpaceae, Leguminosae and Verbanaceae are becoming very rare. This is exemplified by the short supply of Bohol’s Molave or “tugas” (Source: Wikipedia, Dec 12, 2018).

Fauna

Bohol has various animals that are very unique just like the Tarsier.The fauna on Bohol is almost identical to that on Mindanao, Samar, and Leyte, but not that on nearby Negros. Scientists believe that the floral and faunal biodiversity unique to the Philippines is caused by the Ice Age. They also believe that the country has the most severely endangered plant and animal communities on earth. In this page, you will find the origin, conservation status ,ecological role and economic value of each Fauna found in Bohol.

Data about terrestrial fauna in Bohol are scarce. In the few studies conducted in RSPL. Eight mammal species have been identified. These do not include the recent identification of 14 bat species (1 endangered) inside the protected area. Most fauna classes such as reptiles, amphibians and insects fauna animals have not been studied. Recent bird studies have positively identified 56 bird species with 18 more species still unidentified. Actually recorded bird observations in Bohol, mainly near Bilar, go back to the mid 1800. However, there are now birds previously seen on the island that are not positively identified. This includes the Philippine Cockatoo last seen in RSPL in 1995. The most well known animal in Bohol is the Philippine tarsier (see picture below), one of the smallest primates in the world. Although not on international endangered lists, it is fast losing its habitat areas on the island. This is true of Bohol’s flying lemurs, civet cats, wild pigs, grey squirrels and Philippine monkeys. Also included are the fresh fish species that are present in the dam such as: ibís – guppy, kasili, anga, tilapia - Tilapia; Tilapia zili and bangús – milkfish; Chanos chanos. Mud fish, catfish, and gurami.

4.2 Environmental and Social Impact Assessment and Mitigating Measures

Environmental law in the Philippines requires all projects to prepare an Environmental Impact Statement (EIS) Study for the Department of the Environment and Natural Resources (DENR) before an approval and an Environment Compliance Certificate (ECC) could be issued. However, according to a Memorandum of Agreement signed between DENR and Department of Energy (DOE), mini-hydro projects with rated capacities between 1 to 10 megawatts, or with less than twenty (20) million cu. m. water impoundment, need not secure an EIS but instead, submit an Initial Environmental Examination (IEE), which is a simplified version of an EIS2.

2http://www.doe.gov.ph/pecr2005/petroleum/PETROLEUM%20jpg/4.0%20FISCALLEGAL/ .2%20LAWS%20A_D%20ISSUA_CES/4.2b%20 LAWS_CIRCULARS/4.2b.13%20%20PD1586.pdf Nippon Koei Co., Ltd. 4-5 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Social and Environmental Study Main Report Chapter 4

The following table summarizes the environmental and social impact assessment and its mitigating measures:

Table 4.1 Assessment of Potential Social Environmental Impacts and Mitigation Measures Description of Project Development Stage and Potential Environmental & Mitigation Measures Activities Social Impacts Construction Phase 1.0 Site Preparation (Land clearing, Staking, • Loss of terrestrial ecology • Follow and implement the re- etc.) greening design of the area 2.0 Access road construction and/or . Loss of terrestrial ecology; . Make use of existing pathways Improvement . Occurrence of runoff and soil to avoid land area to be erosion; acquired; and minimize . Dust emission increase environmental degradation. turbidity in river systems . Well graded road design with adequate outlets and stable discharge areas . Installation of dikes for soil erosion protection . Installation of silt protector on the discharge area to minimize turbidity of water . Daily watering of newly opened and/or exposed land/ soil to minimize dust emission especially in areas where there are inhabitants. . Avoid burning of removed vegetation. Dispose removed vegetation to designated garbage disposal area. . Encourage local people to make use of removed vegetation such as composting 3.0 Moving in and movement of . Increase dust emission and/or . Daily watering of the access construction heavy equipment, etc. total suspended particles (TSP) road especially in areas where in the air Increase noise and there are inhabitants disturbance to nearby villages. . Working hours must be limited during daytime. . Provision of ear protection equipment to workers in place/s where noise reach 80 (dB(A)). 4.0 Hauling of construction materials, sand, . Soil particles and aggregates . Ensure that trucks hauling soil, gravel, etc. may fall or drop along the road sand and other construction and hit passers-by aggregates are properly and tightly covered 5.0 Construction of Contractors’ camp site and . Loss of terrestrial ecology; . Contractor’s obligation to facilities . Environmental aesthetics restore the area and leaving degradation without hazardous materials that will harm both the humans, flora and fauna in the area

5.1 Workers issues: . Social conflict from poor . Good Camp site and following . Location of camp and employment of location of camp and bias in policy in managing to avoid local labor; employment policy of local conflict among workers; workers not hired . Identified potential project beneficiaries are first priority in the hiring of workers . Provision of adequate living condition . Workers poor health will cause . Provide potable water, well low output balanced and adequate food

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Description of Project Development Stage and Potential Environmental & Mitigation Measures Activities Social Impacts . Use of fuel wood in cooking food and rations; and recreational heating water . Loss of forests trees facilities . Contractor to provide gas and . Hunting of wildlife and plant poaching kerosene for water heating and . Loss of biodiversity cooking food . Contractor must enforce policy and agreement in hiring workers the strict prohibition of hunting wildlife and plant pouching for sale. 5.2 Quarrying of aggregates from designated . Loss of terrestrial ecology; . Contractor’s obligation is to borrow pit area . Environmental aesthetics restore the area by putting it degradation back the topsoil and re-plant the area with what is the existing vegetation it has prior to quarrying activities; . Install dikes to prevent soil erosion 5.3 Installation of construction related . Prevention of construction . Appropriate installation of signages and/or early warning signs to ensure related accidents signages and other warning public, employee and workers’ safety signs in designated areas. 5.4 Construction of the following structures and facilities: . . 5.4.1 Malinao Dam Loss of terrestrial ecology; Contractor’s obligation is to . Environmental aesthetics restore the project site . (1) Mini Hydro Electric Power Development degradation; Avoid burning of removed . Deterioration of water quality; vegetation. Dispose removed 1) Dam HEPP: 290kW, 1,032MWh/year . Loss of aquatic habitat due to vegetation to designated 2) Construction of Hydropower plant the eel, (locally known as garbage disposal area. building kasili) species, mud fish, Encourage local people to 3) Installation of Y shape distribution pipe at catfish, gurami mentioned in make use of removed existing penstock section fauna are migratory in vegetation such as composting. nature and one of its . Installation of silt protector or 4) Installation of hydro electrical- characteristics is their sedimentation trap to minimize mechanical works (turbine, generator, movement going upstream of turbidity downstream of the gate and operating system. the river. Therefore, the project river and hence, avert loss of (2) Improvement of existing dam to will definitely affect eel species aquatic habitat reduce spill out and wasting water use behavior and thus, its natural . Contractor is not allowed to 1) Revision of rule curve habitat will be altered. use Polychlorinated Biphynels 2) Improvement of monitoring system (PCB) as dielectric insulation and/or cooling transformer (rainfall, water level, inflow, outflow, with liquid containing PCB spillout, intake discharge, meteorological due to its potential harmful data, etc.) effects on human health and 3) Improvement of operation and the environment management system of irrigation water use. (3) Improvement of existing spillway of Malinao Dam (already studied by NIA) 1) Heightening of existing spillway by installation of rubber gate of 2 m in height 2) Construction of new auxiliary spillway 3) Heightening of saddle dam (4) Countermeasures for reservoir sedimentation 1) Construction of check dams in upstream tributaries 2) Construction of sediment flushing gate 3) Dredging/excavation of reservoir sedimentation 4) Installation of floating boom and rakes system at intake 5) Watershed management

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Description of Project Development Stage and Potential Environmental & Mitigation Measures Activities Social Impacts 4.2.2 Diversion Chute

(1) Chute HEPP: 1,038kW, 4,491MWh/year (2) Construction of Hydropower plant building

5.4.3 Bayongan Dam

(1) Dam HEPP: 226kW, 630MWh/year (2) Construction of Hydropower plant building (3) Installation of Y shape distribution pipe and penstock (4) Installation of hydro electrical-mechanical works (turbine, generator, gate and operating system

5.5 Clearing and clean up the area within and . Health hazards and risks to . Minimize diseases and surrounding their camp prior and/or upon employees and construction illnesses in the construction project completion workers and surrounding site; inhabitants . This effort will encourage and influence the villagers to clean up their areas Source: The Study Team Henceforth, the proposed project’s impacts do not detrimentally affect environmentally sensitive areas. The Project Proponent must give due consideration to all possible adverse environmental impacts of the project and has committed to adopt mitigation measures as well as to formulate and strictly implement an Environmental Management Plan. Other plans, which will be monitored throughout the construction, operation, and abandonment phases of the project are as follows:

Reforestation Plan:

Every tree cut or removed due to construction activity will have to be replaced for by planting a forest trees. A management plan for clearing of vegetation and reforestation will be prepared. The plan shall establish the protection of vegetation along the river banks and its environs. Cutting of hardwood species will be avoided as much as possible, and these trees will have to be clearly identified prior to initiation of construction activities.

Watershed Management and Protection Plan:

Includes activities such as reforestation, bamboo planting, agroforestry, assisted natural regeneration, erosion control and protection system through adoption of Bio-Engineering Technology (with the use of vetiver grass, hedge rows, SALT[sloping agricultural land technology], gabions, etc) – especially for significant flora and fauna in the area.

Construction/contractors Environmental Plan/Program:

Implement careful engineering, planning, and supervision program to ensure proper management of excavation materials, river and drainage crossings, and reduction of nuisances such as dust, noise, and traffic.

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Social Development Plan:

Includes programs for education, environmental, health, labor and infrastructure development of the community.

Disaster Preparedness Plan:

Covers the installation of a flood warning device and other instruments useful in determining and/or that would be activated during abnormally high flows; and a

Monitoring Plan:

Proper implementation of the mitigation measures and enhancement plan mentioned earlier. The plan will cover the different phases of the project from construction to operation and maintenance and abandonment.

4.3 Laws and Regulations related to the Environment and Social Concerns

4.3.1 Environmental/Social Regulatory Compliance

These are the laws, policies and guidelines that will govern the implementation of the project and following is a brief description of each of the law for the project implementers guidelines:

Philippine Agenda 21 - A concern for making the needs of the future generations known as inter- generational equity

The National Integrated Protected Areas System Act of 1992 (RA 7586) – to protect outstanding and biologically important public lands that are habitat to rare and endangered species of plants and animals; it established categories of protected areas to include strict nature reserve, national parks, etc.

The Water Code of the Philippines (PD 1067) – The basic principles and framework relating to appropriation, control, and conservation of water resources. All waters belong to the State; all waters that belong to the State cannot be subject to acquisitive prescription.

No structures can also be built within a specific distance from the shoreline: meters – urban areas

 20 meters – agricultural areas  40 meters – forest areas No development is allowed within the zone 20 meters from the high water line along sea shores

 The Philippine Clean Water Act of 2004 (RA 9275) – apply to water quality management in all water bodies. Primarily apply to the abatement and control of pollution from land based sources; water quality standards and regulations and the civil liability and penal provisions shall be enforced irrespective of sources of pollution.  The Clean Air Act of 1999 (RA 8749) – It covers a holistic program on air pollution management. The focus is on pollution prevention rather than pollution control.

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 Ecological Solid Waste Management Act of 2000 (RA 9003) – Sec. 16 “the province, city or municipality, through its local solid waste management boards, shall prepare its respective 10-year solid waste management plans”  The National Climate Change Act of 2009 (RA 9729) – it covers the seven thematic areas of: food security, water sufficiency, ecological and environmental stability, human security, climate-smart industries and services, sustainable energy, and knowledge capacity development.  The National Disaster Risk Reduction (RA 10121) – it covers the thematic areas of: disaster prevention & mitigation, disaster preparedness, disaster response and disaster rehabilitation & recovery The Department of Environment and Natural Resources (DENR) Administrative Order No. 30 Series of 2003. This is a Revised Procedural Manual for DAO 2003-30 is hereby being adopted and superseding the Procedural Manual (First Edition) for DAO 2003-30 issued as MC 2005-01 on January 5, 2005. This revised Manual integrates DENR MC 2007-08 issued on 13 July 2007 segregating from the EIA process the practice of prior submission of permits, clearances, licenses and other similar government approvals outside EMB mandate. This revised Manual also integrates other EMB MCs issued in 2006 which provide for a) clarification in the PEISS implementation guidelines (MC 005 issued on 19 December 2006) b) improvement in the ECC format/content for more timely and substantive advice of EIA Recommendations to other government entities for their consideration in their decision-making process (MC issued 22 December 2006) and c) a manual on guidelines for focusing EIA review to the most significant issues (EMB MC 2007-01 issued 09 March 2007.

4.3.2 The Environmental and Natural Resource Management Mandates of the LGU

The environmental and natural resource management mandates of the LGUs are described in the Act as below:

i) Adopt adequate measures to safeguard and conserve land, mineral, marine, forest and other resources - Municipal Mayor ：Sec. 444（b）（ 3）（ vii）, RA 7160 - City Mayor ：Sec. 455（b）（ 3）（ vii） - Provincial Governor ：Sec. 465（b）（ 3）（ v） ii) Protect the environment and impose appropriate penalties for acts which endanger the environment such as dynamite fishing and other forms of destructive fishing, illegal logging and smuggling logs, smuggling of natural resources products and endangered species of flora and fauna, slash and burn farming, and such other activities which result in pollution, acceleration of eutrophication of rivers and lakes or of ecological balance. - Municipal Mayor ：Sec. 447（a）（ 1）（ vi）, RA 7160 - City Mayor ：Sec. 458（a）（ 1）（ vi） - Provincial Governor ：Sec. 468（a）（ 1）（ vi）

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4.3.3 Specific laws, Policies and Guidelines, Ordinances in Bohol

Here are the specific laws, policies and guidelines, ordinances approved and being implemented by the Provincial and Municipal Government Units of Bohol:

1) The Bohol Environment Code contains a number of policies intended to preserve, protect and conserve the island province’s water resources, including minimization of pollution in ground and surface waters. 2) The policy of the provincial government is to ensure the perpetual existence of adequate forest resources for the use and enjoyment of Boholanos through local government driven, inter-agency and multi-sectoral forest resources management. There are areas in protection forest that need to be indicated in respective management plans. Examples of these are Rajah Sikatuna Protected Landscape, Loboc Watershed Forest Reserve and Alijawan- Cansuhay-Duero Watershed. There are also non-forested timberland areas and woodlands in Alienable and Disposable lands that can be used for reforestation and additional tree farming. Some of these areas are found in Wahig-Inabanga Watershed, Abatan Watershed, Carood Watershed and Ipil Watershed 3) Environmentally Critically Areas (ECAs) are areas covered by Presidential Proclamation 2146 but not belonging to environmentally constrained areas. They also impose limitations in terms of land use development. Non-suitable land uses should be disallowed in these areas. In addition there are areas degraded through intensive agricultural use, erosion and mining and quarrying that need to be rehabilitated. 4) National Integrated Protected Area System’s (NIPAS Act or RA 7586) Environmentally Constrained and Environmentally Critical Areas and latest data shows that Bohol has a total of 75,766 hectares under protection. 5) In December 2008, the Bohol Mining Ordinance was approved and adopted by the Honorable Members of the Sangguniang Panlalawigan that regulates the issuance of small- scale mining permits, quarry permits, sand and gravel extraction permits, government and private gratuitous permits, commercial and gratuitous guano permits, gemstone gathering permit, pebble extraction permit and other special permits. It establishes the mechanics of issuances; imposes taxes on extracted materials; and provides penalties for violations of certain provisions. It further defines that the Provincial Governor has the power to issue permits to extract these types of resources within the territorial jurisdiction of the province as amended under R.A. 9742, The Philippine Mining Act of 1995. To fully implement the Provincial Ordinance, the Governor has created and deputized a Task Force Kalikupan to monitor the province-wide mineral operation and watch for illegal haulers in consonance with the existing laws and regulations. The record shows that there 139 permittees who are engaged in sand and gravel extraction.

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6) The joint DA/BFAR and DENR General Memorandum Order No. 3, Series of 1991, tried to respond to the problem of idle, unproductive, abandoned and/or illegal fishpond areas by reverting them into their original classification of timberland. 7) Republic Act 8550 (The Philippine Fisheries Code of 1998, Chapter 1, Section 4(58)). Philippine Fisheries Code of 1998 and the Bohol Environment Code, the national government recognized that a paradigm shift was needed to adequately provide for the development, management and conservation of coastal resources. 8) The Provincial Government of Bohol is one of six pilot provinces in the country that has actively implemented the Local Development Action Plan for Climate Change in partnership with the Institute of Climate, Energy and Environment (ICLEE) and a full- pledged and active member province in the International Council for Local Environmental Initiatives (ICLEI) since 2002.

4.4 Institutional and Administrative Framework

This institutional and administrative framework will guide the project proponent which is the National Irrigation Administration (NIA) on how to go about the development of hydropower project in Malinao, Bayongan and Capayas Dams/Reservoirs located in Municipalities of Pilar and Ubay, respectively.

The NIA which is the project proponent shall coordinate with the Department of Energy where the latter is mandated by virtue of Republic Act 7638 (Department of Energy Act of 1992) to prepare, integrate, coordinate, supervise and control all plans, programs, projects and activities of the Government relative to energy exploration, development, utilization, distribution and conservation. In line with this, at the initial stage, the National Irrigation Administration (NIA) will submit the following to DOE: (1) Letter of Intent (LOI) and (2) Maps/Coordinates of the proposed three (3) project sites. While preparing the two (2) requirements, the NIA must coordinate with the Provincial Government of Bohol and the Municipalities of Pilar and Ubay for their consent, knowledge and participation in the preparation of all the requirements listed in the attached form.

In order to accomplish the listed requirements, the NIA will coordination with the following government and non-government organizations such as DENR for securing the Environmental Compliance Certificate (ECC), NGCP to get the proof of system distribution impact study, existing power generation company in the locality, LGUs – for acquiring the proof of land use, and to complete the other listed requirements.

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CHAPTER 5 FINANCIAL AND ECONOMIC VIABILITY

5.1 Cost Estimation of the Project

Construction cost is roughly estimated based on technical reference book, "Guidebook for Medium/Small Scale Hydropower" by New Energy Foundation, Japan. The guidebook provides the regression formula to estimate the costs based on variable parameters such as power discharge, effective head, maximum power output in the existing projects. Unit construction costs in Philippine market are applied for the cost estimation of civil works and architectural work. The costs of machine facility and electric facility are quoted from those in the guideline book.

The result of cost estimation is presented below. The total direct construction cost of the Diversion Chute HEPP is estimated at 252.2 Million Peso.

Table 5.1 Direct Construction Cost of Diversion Chute HEPP

Source: The Study Team

The cost for improvement of irrigation telemeter system is estimate as below:

i) Improvement of Malinao irrigation scheme: xxxxxxxxyen, ii) Improvement of Bayongan irrigation scheme: xxxxxxxxyen, iii) Operational maintenance cost: xxxxxxxxxxyen (Bohol irrigation district system as a whole)

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5.2 Preliminary Financial and Economic Analysis

In implement the priority project, incremental energy supply and increase of agricultural crops are expected as the benefit. In this chapter, the financial and economic viability are evaluated comparing the cost and revenue as well as economic benefit.

Firstly, the assumptions are summarized. Then, the project cost is estimated, and financial and economic evaluation are conducted based on estimated revenue and economic benefit.

5.2.1 Basic Assumptions

Basic assumptions used for financial and economic evaluation are shown in the following table.

Table 5.2 Basic Assumptions for Financial and Economic Analysis

Factor Number Comment PHP 1 = JPY 2.12 Exchange Rate As of Dec. 2018 USD 1 = PHP 53.13 Evaluation Period 34 years Preparation : 4 years, Operation : 30 years Generally used value for the Feasibility Social Discount Rate 10% Study of JICA and other donors SCF (Standard Conversion Generally used value for the Feasibility 0.9 Factor) Study of JICA and other donors Official Discount Rate in the Fixed Interest Rate of National Treasury 7.096% Philippines Bond for 10 years as of Dec., 2018 Expected Return Rate of 15.0% Based on the interviews to investors. Equity WACC (Weighted Average Calculated by the above interest rates and 8.68% Cost of Capital) share of project fund (equity:loan = 2:8) Source: The Study Team

5.2.2 Project Cost

The project cost including capital investment cost and O&M cost is summarized. Both financial cost and economic cost are calculated. For financial analysis, only power generation system is included to judge its financial viability. Whereas for economic analysis, economic costs of power generation of Diversion chute, irrigation telemeter system, Malinao Dam heightening and new irrigated area development cost are included to know the social impact of optimum dam operation in addition to power generation.

Initial Investment Cost

Direct costs of power generation and telemeter system are referred from Chapter 3.4 of this report. Consultant cost (estimated as 10% of direct cost) and price contingency (10% of both direct cost and consultant cost) are added to have a total project cost. In addition, the administration cost of counterpart organization is estimated at 2% of total cost. The project schedule is made simply to be 4 years of consultant work (preparation 2years + supervision 2 years), and the construction of the latter 2 years of the said period. Other costs such as price contingency and tax are excluded based on the principle of

Nippon Koei Co., Ltd. 5-2 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Financial and Economic Viability Main Report Chapter 5 financial and economic analysis. The construction costs of Malinao Dam heightening and new irrigated area development are roughly estimated by the study team for the evaluation.

The economic cost is calculated considering the equipment cost described in chapter 3.4.3 as foreign currency portion and the other part is local currency portion. The Standard Conversion Factor (SCF) of 0.9 is multiplied to the local cost portion.

Table 5.3 Financial Cost and Economic Cost of Initial Investment Cost

(unit: thousand PHP) Year Dam Total 2019 2020 2021 2022 Malinao xxxxx xxxxx xxxxx xxxxx xxxxx Financ Diversion Chute xxxxx xxxxx xxxxx xxxxx xxxxx ial cost Bayongan xxxxx xxxxx xxxxx xxxxx xxxxx Total xxxxx xxxxx xxxxx xxxxx xxxxx Malinao xxxxx xxxxx xxxxx xxxxx xxxxx Diversion Chute xxxxx xxxxx xxxxx xxxxx xxxxx Econo Bayongan xxxxx xxxxx xxxxx xxxxx xxxxx mic Irrigation Telemeter System xxxxx xxxxx xxxxx xxxxx xxxxx cost Malinao Dam Heightening* xxxxx xxxxx xxxxx xxxxx xxxxx New Irrigated Area* xxxxx xxxxx xxxxx xxxxx xxxxx Total xxxxx xxxxx xxxxx xxxxx xxxxx

Note: Construction costs of Malinao Dam heightening and new irrigated area development are roughly estimated by the study team Source: The Study Team

O&M Cost

O&M cost is estimated based on the past record of the similar projects. Economic cost is calculated as multiplying the SCF at 0.9 to the financial cost.

Table 5.4 Financial Cost and Economic Cost of O&M Cost

(thousand PHP/year) Dam Financial Cost Economic Cost Malinao xxxx xxxx Diversion Chute xxxx xxxx Bayongan xxxx xxxx Irrigation Telemeter System xxxx xxxx Malinao Dam Heightening* xxxx xxxx New Irrigated Area xxxx xxxx Total xxxx xxxx Note: Additional O&M cost of Malinao Dam Hightening is estimated at 0 as the dam is already operated by NIA regional office. The production cost of paddy is considered in the calculation of benefit per ha, and not included as the O&M cost. Source: The Study Team

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5.2.3 Financial Analysis

To evaluate the financial viability of the power generation, revenue and cost of three generation systems are evaluated.

Revenue is estimated based on the actual sales revenue of electricity generated by hydro power system. Revenue of providing irrigation water is not included as the irrigation service fee became free for farmers owning smaller than 8 hectares in accordance with the policy of the president Duterte after 2018.

Incremental Revenue of Power Generation

Sales revenue of electricity is estimated by multiplying the annual generated electricity and the sales price, and the revenue paid to NIA is subtracted.

“Sales Revenue of Electricity (kWh)”

= “Annual Generated Electricity (kWh)” × “Sales Price (PHP/kWh)” × “1－(Revenue Rate of NIA)”

Generated electricity is quoted from Chapter 3.4.3 of Operation D (minimum discharge of 2 m3), and the stop rate at 5% is applied.

Regarding the sales price, the average sales price of Boheco II, the actual buyer of the electricity in case the project is implemented, is calculated using the past record from December 2017 to July 2018. During such period, the average price was 4.38 PHP/kWh in total, and 5.29 PHP/kWh for sales through the long-term mutual agreement. In comparison, the average sales price in whole Philippines in 2016 was 5.50 PHP/kWh according to “Rural Electrification Chronicle 2014-2016” issued by the National Electrification Administration. Also the FIT price for hydro power generation project was set at 5.90PHP/kWh.

Assuming the Project is implemented, the electricity will be sold based on mutual agreement made with Boheco II, the actual sales price by the similar agreements, 5.29 PHP/kWh is selected for the calculation.

The revenue share with NIA is also considered as the dam used for the project is owned by NIA. Based on the past similar project, 6% of total revenue is estimated to be provided to NIA from project implementing entity.

Table 5.5 Revenue of Power Generation

Dam Power Generation Sales Price Revenue Malinao (operation D) 804,650 kWh/year 5.29 PHP/kWh 4,001,203 PHP Diversion Chute (operation D) 4,266,450 kWh/year 5.29 PHP/kWh 21,215,349 PHP Bayongan (operation D) 598,500 kWh/year 5.29 PHP/kWh 2,976,101 PHP Total 5,669,600 kWh/year 5.29 PHP/kWh 28,192,653 PHP

Source: The Study Team

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Result of Financial Analysis

Result of financial analysis, FIRR and NPV, calculated by the estimated cost and revenue are shown in the following table. Under the base case, values of FIRR became xxxxx for Malinao Dam, xxxxx for Diversion Chute, and xxxxx for Bayongan Dam. All FIRR values are lower than the criteria of WACC, which is 8.63%, and the financial viability of the project is judged low.

To make the financial viability higher, the use of subsidy called “Joint Crediting Mechanism (JCM)”, explained in latter chapter 9.2.2, is expected. Already 3 similar projects are applied for the subsidy, 30% of investment cost (conditions later than 4th approved project in the same sector) is assumed to be subsidized by JCM. Under the JCM subsidized case, values of FIRR improved by 1.5% to 2.7% and they became xxxxx, xxxxx, xxxxx respectively for each system. The FIRR value is higher for Diversion Chute, but the value of xxxxx with 30% subsidy is still lower than the WACC (8.68%). ｘｘｘｘｘｘ ｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘ ｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘ

Table 5.6 Result of Financial Analysis

Base Case 30% JCM subsidy Case Dam FIRR NPV FIRR NPV Malinao xxxx xxxxxxxxxx xxxx xxxxxxxxxx Diversion Shute xxxx xxxxxxxxxx xxxx xxxxxxxxxx Bayongan xxxx xxxxxxxxxx xxxx xxxxxxxxxx Total xxxx xxxxxxxxxx xxxx xxxxxxxxxx

Source: The Study Team

5.2.4 Economic Analysis

In this chapter, economic viability is judged by comparing the expected economic benefit and economic cost (estimated in 5.2.2). Two economic benefits, incremental electric generation and increase in paddy production, are quantified for the analysis. According to the evaluation in 3.4.4, the result under following three alternative cases are calculated.

Case１ : Power generation (minimum discharge of 1m3) + Incremental irrigated area (rehabilitation of planned area, 2,147ha)

Case 2 : Power generation (minimum discharge of 2m3) + Incremental irrigated area (Case1 + triple cropping of existing area, 2,759ha)

Case 3 : Power generation (minimum discharge of 2m3) + Incremental irrigated area (Case2 + new irrigated area, 3,983ha)

In terms of the cost, the power generation system of Diversion Chute is only included as the other two systems are judged as not financially viable by financial analysis. The cost of installing telemeter system

Nippon Koei Co., Ltd. 5-5 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Financial and Economic Viability Main Report Chapter 5 and dam heightening are included in all alternative cases. The cost of developing new irrigated area is only included in Case3.

Economic Benefit of Incremental Power Generation

Economic benefit of electric generation is calculated by multiplying the annual generated electricity and marginal cost of generation.

“Economic Benefit of Power Generation (PHP)”

= “Annual Generated Electricity (kWh)” x “Average Sales Price (PHP/kWh)”

“Annual Generated Electricity (kWh)” is calculated similar to the financial analysis quoting the data in Chapter 3.4.3.

Generally, marginal cost is used as the value of electricity to calculate the economic benefit. However, such data is not available in the Philippines, the “average sale price” of electricity in the country in 2016 is used alternatively. If there are no special constraints, the electricity is generated by more economical alternative way to economize the cost, and the future marginal cost tends to increase as the country continue developing. Therefore, using the current average cost instead of marginal cost results in smaller benefit amount, and it is appropriate in accordance to the principle of conservatism of economic analysis. The value of 5.50PHP/kWh is used for the calculation referred from “Rural Electrification Chronicle 2014-2016”.

Table 5.6 Economic Benefit of Power Generation

Dam Power Generation Marginal Cost Economic Benefit Diversion Shute (Case1, 1m3) 3,305,050 kWh/year 5.50 PHP/kWh 18,177,775 PHP Diversion Shute (Case2, 2m3) 4,266,450 kWh/year 5.50 PHP/kWh 23,465,475 PHP

Source: The Study Team

Increase of Paddy Production

Increase of paddy production is figured out by multiplying the “incremental productive rice field”, “average yield of paddy” and “economic value of paddy”

“Benefit of Increase of Paddy Production” = “Incremental Productive Rice Field (ha)” x “Average Yield of Paddy (ton/ha)” x ”Economic Value of Paddy (PHP/ton)」

Table 5.7 Indicators for Economic Benefit of Increase of Paddy Production

Indicators Figures Data Source Case1 (1m3): 2,147 ha Incremental Productive Rice Case2 (2m3): 2,759 ha Study Team Field Case3 (2m3): 3,983 ha Average Yield of Paddy 4.33 ton/ha (Jan.-June 2017) National average yield in irrigated rice field in

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4.52 ton/ha (July-Dec. 2017) 2017. (Selected Statistics on Agriculture 2018) Calculated by subtracting “average production cost of irrigated palay” out of “average Economic Value of Paddy 5,890 PHP/ton farmgate price of palay” in 2017. (Selected Statistics on Agriculture 2018) Source: The Study Team

1) Incremental Productive Rice Field

As described in the Chapter 3.4.4, cultivated rice field is estimated to increase by 2,147ha, 2,759ha and 3,983ha under Case1, Case2 and Case3, respectively.

2) Average Yield of Paddy

The average yield of paddy at irrigated area is quoted from the “Selected Statistics on Agriculture 2018” issued by PSA (Philippines Statistics Authority). The most recent data in 2017 is used for the calculation.

Table 5. 8 Average Yield of Irrigated Land in the Philippines

Year Jan. - June July – Dec. Average 2015 4.51 4.13 4.31 2016 4.40 4.13 4.26 2017 4.52 4.33 4.42 Source: Selected Statistics on Agriculture 2018 (PSA)

3) Economic Value of Paddy

Economic value of paddy is calculated based on the average profit referring to the “Selected Statistics on Agriculture 2018” issued by Philippines Statistics Authority (PSA). The average sales price was 18.21 PHP/kg, whereas average cost of irrigated rice field was 12.32 PHP/kg, and the profit which is the difference of sales price and cost is 5.89 PHP/kg (5,890 PHP/ton).

Result of Economic Analysis

Comparing the estimated economic cost and economic benefits, the EIRR under three alternative cases become as shown in the table below. EIRR of Case1 is lower than the hurdle rate at 10%, but the EIRR values surpass the 10% under Case2 and Case3 and the project is considered as economically viable. ｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘｘ

Table 5.8 Result of Economic Analysis

Total Project EIRR NPV B/C Case1 (1m3) xxxx xxxxxxxxxxxxx xxxx Case2 (2m3) xxxx xxxxxxxxxxxxx xxxx Case3 (2m3) xxxx xxxxxxxxxxxxx xxxx

Source: The Study Team

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CHAPTER 6 IMPLEMENTATION SCHEDULE OF THE PROJECT

The estimated implementation schedule of “the project for improvement of the Malinao Dam spillway” that will be implemented by the national budget of the Government of the Philippines is shown below.

Table 6.1 Implementation Schedule of Improvement of Malina Dam Spillway

Item 2019 2020 2021 2022 2023 2024 Improvement of Malinao Dam Spillway（the study was 2 completed by NIA, and Bid is being undertaken under GOP 2-1 Bid of Construction Works

2-2 Contract of the Construction Works

2-3 Construction Works

2-4 Test and Inspection

2-5 Start of Operation Legend NIA Project(under GOP fund) (* Schedule is estimated one by the Study Team） Source: The Study Team The implementation schedule of the proposed project for “Restoration and Upgrading Dams in Bohol Irrigation Project” is presented in table below. The schedule is prepared considering the application of the Japanese ODA project (Yen Loan) because the main implementing agency will be NIA. The Construction works is estimated to be started after three (3) year of the MOA.

Table 6.2 Implementation Schedule of the Project

1 year 2 year 3 year 4 year 5 year 6 year

Restoration and Upgrading Dams in Bohol Irrigation Project

Hydropower Provision in Irrigaion Dams, Improvement of Irrigation Water Management System, Countermeasures 1 for Sedimentation in Malinao Dam (assumed to be applied the Japanese Yen Loan)

1-1 Endorsement, MOA Basic Design, Preparation of Bid Documents, Bid Evaulation 1-2 Criteria, and Approval of Bid Drawings 1-3 Appraisal, Procurement for the Project

1-4 Bid and Selection of the Implementing Consultants

1-5 Detailed Engineering Design

1-6 Permit and Approval of Socio-Environmental Activities

1-7 Permit and Approval of Hydroper Genration Plans, etc.

1-8 Construction Supervision

1-9 Bid of Construction Works

1-10 Contract of the Construction Works

1-11 Construction Works

1-12 Test and Inspection

1-13 Start of Operation

Legend Japanese ODA Projects

Source: The Study Team

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CHAPTER 7 CAPABILITY OF IMPLMENTING AGENCY

7.1 Outline of Implementing Agency

The organization chart of NIA that will be an implementing agency is shown below

Source：NIA

Figure 7.1 NIA Organization Chart

7.2 Organization for Project Implementation

Regarding the small hydropower development of existing irrigation facilities, the Technical Working Group on Small Hydropower Development was established within the Operation Department in the above NIA organization chart, and centrally managed for small hydropower generation in national irrigation scheme. The IPP company conducts FS with the approval of FS implementation from the Technical Working Group mentioned above and after the FS IPP company conducts the project after obtaining approval on business.

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In addition, the organization chart of Region VII Office which has jurisdiction over BOHOL irrigation district is as follows. The implementation structure when carrying out the power generation project using the BOHOL irrigation facility is as shown in Figure 7.2 below, in that case 6% of the profits obtained from the small hydropower project is paid to Region VII Office as a facility use fee.

Office of the Department Manager

Engineering & Dam & Reservoir Administrative & Operation Division Division Finance Division

Institutional Administrative Development Section Section

Engineering Section Finance Section

Operations Section Malinal Bayongan Capayas SRIPS

Equipment Section

Operation & Maintenance Administrative & Finance Section Section

Supervising Engineer SWRFT WRFO for Operation

Supervising Engineer for maintenance

Figure 7.2 Organization Chart of NIA Region VII Office

Regarding the operation of irrigation water, it is under the jurisdiction of the Operation & Maintenance section, but if small hydropower generation is attached, close cooperation with Dam & Reservoir Division, which has jurisdiction over dam management will be necessary.

7.3 Capacity of Implementing Agency and Necessary Measures

The NIA has enough capacity to implement the proposed projects in general because NIA has conducted several development project of -electric power plant provided in the dams owned by NIA, and is undertaking operation, maintenance and management of them. For future implementation and operation of the Project, following measures are expected to be necessary:

 Capacity development of operation and management of dam, and restoration and upgrading of dams under operation  Increase of number of staff for facility management and dam operation management, and capacity development  If IPP participates to the operation and management, the said 6% of the management fee would be paid to NIA and used for the operation and maintenance of the facilities and equipment. The guideline and procedure for this cost distribution system shall be discussed among the related agencies.

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CHAPTER 8 ADVANTAGE OF TECHNOLOGY AND OTHER ASPECTS OF JAPANESE COMPANIES

8.1 International Competitiveness and Possibility of Japanese Companies' Getting Orders for Projects (by Equipment, Goods and Services)

8.1.1 Analysis of Strengths and Weaknesses of Japanese Companies and Overseas Competitors in Related Sector

The strengths and weaknesses of Japanese companies in the reconstruction and rehabilitation of dams are as follows.

(1) Strengths

 The strength of Japanese companies in the research and design phases is their ability to plan and design reconstruction and rehabilitation works on the basis of their work experience in implementing such works while operating reservoirs.  As mentioned above, the implementation of construction works while operating reservoirs will minimize the influences of the construction work on the supply of power or irrigation water.  Japanese companies enable facilities requiring no maintenance to be developed, thereby curbing long-term maintenance and management costs.  Japanese companies enable dam operation to be optimized though the introduction of an advanced observation and monitoring information system comprising a high-performance radar rain gauge such as XRAIN.

(2) Weaknesses

 Japanese companies require high initial costs.  Although it depends on the type of equipment, replacing broken parts of Japanese equipment is generally expensive and can require a long time if there are no agents of the Japanese manufacturers.  Japanese companies require local staff to have the abilities needed for optimal dam operation (and optimal dam operation will require expensive support of Japanese companies).

8.1.2 International Competitiveness of Japanese Companies in Related Sector

Japanese companies have developed the most advanced technologies in the reconstruction and rehabilitation of dams and these technologies have been materialized as 1) raising the heights of existing dams to increase reservoir volumes, 2) addition of water discharge facilities, and 3) countermeasures against sedimentation.

In the construction to raise the height of an existing dam, flood control and water utilization plans may be revised to achieve more efficient water distribution in addition to the increase in reservoir volume. In such a case, in addition to the construction to raise the height of an existing dam, there will be a need

Nippon Koei Co., Ltd. 8-1 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Advantage of Technology and Other Aspects Main Report of Japanese Companies Chapter 8 for implementing the expansion of an existing spillway gate or the addition of a new one, which require advanced construction technologies; moreover, there is a possibility of the renovation of an existing water intake.

Also, the Japanese advanced technologies that enable dam reconstruction to be implemented with water stored in a reservoir can minimize the time required to suspend power generation. Thus, although the construction costs increase, Japanese companies still have a great advantage in economic efficiency in terms of the minimized loss in power generation during the dam reconstruction compared to the case of implementing dam reconstruction by draining water from a reservoir and completely stopping power generation during that time. In addition, in a country like the Philippines with a clear distinction between rainy and dry seasons, dam reconstruction that requires the irrigation water supply to be suspended with water drained from a reservoir in a dry season may not be approved because of the adverse effects on agricultural production downstream. Considering the necessity of the water discharge by a dam to maintain waterflow in downstream areas and the maintenance and management costs of dam gate facilities in the future, Japanese companies are considered to have an advantage in terms of superior technological strength to the competitors in other countries.

Countermeasures against sedimentation include a sand elimination bypass tunnel and the construction of a new intake gate associated with the renovation of a water intake. In particular, duplex phase stainless steel is very effective in terms of strength and the facilitation of maintenance work when used for the renovation of locks, gates, and water intake facilities and the Japanese new and original technology to produce such steel boasts unrivaled international competitiveness. The details of the technology are explained later.

8.1.3 Application of Japanese Technologies to Related Sector

As previously mentioned, the dams in the Philippines are classified into two main types, one with power generation and the other without power generation.

The Japanese technologies that can be individually applied to the dams with power generation are dam inspection and diagnostic technologies, research and construction technologies while maintaining dam operation, recycling of existing facilities and proximity construction, sedimentation protection technology, construction technologies associated with raising dam heights and expanding water discharge facilities. In addition to these individual technologies, there is a possibility of presenting a package proposal integrating a financial scheme, a post-construction rehabilitation program, and improvement in maintenance and management capability.

In contrast, the Japanese technologies that can be individually applied to the dams without power generation (reconstruction of irrigation dams) are small hydropower generation technologies (promotion of downsizing and streamlining) and new materials (for maintenance-free operation, improvement in abrasion resistance and weight saving). A package proposal is also possible.

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Group 2: existing dams without hydropower generation storage

Small hydroelectric development with irrigation dam Japanese Technology Selection of Small hydropower potential dam Element technology • Small hydraulic development technology (miniaturization, high Formulation of Upgrading efficiency) Dams Plan • New materials (maintenance free, improved wear resistance, light weight) etc. Development of small hydropower Packaged development ・ F/S ・ Proposal of financial scheme Application to a high-priority ・ Improvement work ・ Improve management ability dam and hydroelectric power station 68

Source: The Study Team

Figure 8.1 Application of Japanese Technologies in Dam Sector (left: a dam with power generation, right: a dam without power generation)

8.1.4 Examples of Japanese Technologies Applied to Related Sectors

Countermeasure for sediment in Wonogiri multipurpose dam in Indonesia

In 1982, the Wonogiri multipurpose dam was constructed in Indonesia with the financial assistance of the OECF (currently JICA). It is a rockfill dam with a height of 40 m and a reservoir volume of 735 million m3 and has been used for irrigation, flood control and power generation.

The dam has been facing a reduction in power generation capacity in rainy seasons due to sediment in front of a water intake since around 2000. Thus, JICA's grant aid was extended to dredge the sediment in front Figure 8.2 Schematic drawing showing the of the water intake as an emergency measure outline of countermeasure against sedimentation at and the research design after the dredging to Wonogiri dam in Indonesia (sediment dam and establish a permanent measure. The sand trap construction) construction for the permanent measure has been underway since 2010. Currently, the construction is in the second phase and is being conducted by a Japanese company because the construction requires advanced technologies in ground improvement.

Kulekhani dam water intake renovation project in Nepal

The Kulekhani dam is the only seasonally adjustable dam exclusively used for power generation in Nepal and it has been assuming the role of supplying power to the capital city of Kathmandu. A flood

Nippon Koei Co., Ltd. 8-3 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Advantage of Technology and Other Aspects Main Report of Japanese Companies Chapter 8 that occurred in July 1993 caused a huge volume of sediment to flow into the reservoir with the surface of the sediment reaching a few meters below the water intake.

For the purpose of preventing the water intake from being buried in sediment in the future, a water intake renovation project was planned, designed and implemented. The renovation project to prevent sediment from flowing into the water intake comprises the installation of a diagonal sluice structure through which water can be guided into the water intake in accordance with the vertical fluctuations in the water level of the dam and a mechanism to enable the diagonal sluice structure to be vertically moved with detachable concrete plates (stop logs) arranged one above the other from the bottom. The diagonal sluice structure was installed using the inverted lining method in which the structure is built from the top down so as to enable installation work to be implemented while operating the dam and thereby enabling the period during which power generation had to be suspended for construction to be minimized.

(3) Nam Ngum No. 1 hydropower station expansion project

The Nam Ngum No. 1 dam is one of the largest dams exclusively used for power generation in Laos and has been assuming the role of supplying power to the capital city of Vientiane and surrounding areas. The first phase of the Nam Ngum No. 1 dam was completed in 1971 and the installed power generation capacity was increased as the project progressed to the second and third phases and reached 155 MW with 5 generators by 1984.

Laos had a large power demand with an annual increase of more than 10% from 2001 to 2014. In contrast, although blessed with rich water resources particularly in northern areas, Laos has largely relied on imported power from neighboring Thailand, Vietnam and China due to lagging infrastructure development and the imported power has been aggravating the country's trade deficit. The proposal of expanding the power generation capacity of the Nam Ngum No. 1 power station in the 1995 master plan opened the door to several power station expansion plans being proposed since the feasibility study conducted in 2008. The optimal plan that was finally selected was to install the 6th generator between the existing power station and the spillway gate so as to guide water into the generator via the shortest route through a buried hydraulic steel pipe penetrating the existing dam body.

アクセス・ルート

バルクヘッド バルクヘッド 取水口ゲート

アクセスルート 貫通部

Before penetration After penetration

Figure 8.3 Nam Ngum No. 1 hydropower station expansion project (left: layout of the

6th generator, right: double-sheet-pile coffer dam structure under construction)

Nippon Koei Co., Ltd. 8-4 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Advantage of Technology and Other Aspects Main Report of Japanese Companies Chapter 8

8.1.5 Application of New Material (Duplex Stainless Steel）

One of the countermeasures for dam recovery and capacity enhancement is to modify water gate, gate, water intake facility, etc. We examined the application of duplex stainless steel which has the technical advantages of Japanese companies as their material

Overview of duplex stainless steel

Duplex Stainless Steel is a kind of stainless steel made into a duplex structure of ferrite and austenite by adding an appropriate amount of Ni to Cr which is a main element of stainless steel.

By adjusting the amounts of Ni and Mo, N, the duplex stainless steel has wide corrosion resistance variation up to the lean, standard and super stainless steel.

Table 8.1 standard values of mechanical properties. Duplex stainless steel is classified into three for each corrosion resistance.

Table 8.1 Mechanical properties of duplex stainless steel (standard value: JIS G 4304)

0.2% PS TS EL Hardness Class JIS (N/mm2) (N/mm2) (%) HBW Lean SUS821L1 ≧400 ≧600 ≧25 ≦290 ≦32 ≦310 duplex SUS323L ≧400 ≧600 ≧25 ≦290 ≦32 ≦310 Standard SUS329J3L ≧450 ≧620 ≧18 ≦302 ≦32 ≦320 duplex SUS329J4L ≧450 ≧620 ≧18 ≦302 ≦32 ≦320 Super SUS327L1 ≧550 ≧795 ≧15 ≦310 ≦32 ≦330 duplex Austenitic SUS304 ≧205 ≧520 ≧40 ≦187 ≦90*1 ≦200 stainless SUS316L ≧175 ≧480 ≧40 ≦187 ≦90*1 ≦200 steel

*1:HRB Source: Japan Industrial Standard

Characteristics of duplex stainless steel

1) 1) Mechanical properties

In applying duplex stainless steel to structures, mechanical properties are important properties. Duplex stainless steel group has high strength, 0.2% proof stress of the lean duplex stainless steel is about twice as high strength as compared with SUS304, SUS316L. Because of this high strength, it is possible to reduce the design thickness, which makes it possible to reduce the weight and the steel materials used. Figure 8.4 shows a case where the design was re-examined utilizing its high strength. It was designed and manufactured with SUS821L1 so as to have the same critical load as the steel pipe and the welded H-shaped steel manufactured by SUS304.

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Both the steel pipe and the welded H-shaped steel can be designed to be thinner with high strength, and the weight ratio can be reduced by about 40%.

In general, when stainless steel is applied, it is said that initial investment will increase due to high steel price. However, when designed and manufactured with high strength duplex stainless steel, it is possible to reduce the initial steel purchase amount by reducing the plate thickness, which indicates that the initial investment can be reduced.

Source: Created by the Study Team

Figure 8.4 Example of weight reduction of structural steel by applying SUS 821 L 1

2) Corrosion resistance

Figure 8.5 shows the positioning of the characteristics of duplex stainless steel with austenitic stainless steel. The horizontal axis shows pitting corrosion resistance by CPT (Critical Pitting Temperature), and the higher the critical temperature, the higher the pitting corrosion resistance in chloride. The vertical axis shows 0.2% proof stress as strength. For the austenitic stainless steel showing equivalent CPT, the yield strength of lean duplex stainless steel is about twice as high.

Nippon Koei Co., Ltd. 8-6 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Advantage of Technology and Other Aspects Main Report of Japanese Companies Chapter 8

Source: The Study Team

Figure 8.5 Positioning of duplex stainless steel

When stainless steel is applied as a structure, most of it is used outdoors. Figure 8.6 shows the results of exposure tests of SUS 821 L 1 and SUS 304 on the coastal piers for 1 year. Although SUS 304 markedly rusted, SUS 821 L 1 has good corrosion resistance although there are a few points rust.

Source：Overview of the duplex stainless steel（JSSC 2014, AUTUMN No.19）

Figure 8.6 Exposure test results of SUS 821 L 1 and SUS 304

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Application case and applicability of duplex stainless steel

1) Material selection of stainless steel flood gate

Flood gates are often used after painting on carbon steel, but when stainless steel is used, austenitic stainless steel is generally applied. SUS 304 is used in freshwater environments, and SUS 304 N 2 is used for components that require strength and hardness. SUS 316 L and SUS 329 J 4 L have been applied to environments with high salt concentration such as wetted parts of the tide water gate.

2) Application of lean duplex stainless steel

The lean duplex stainless steels introduced in the previous section are about twice as high as the conventional steel and have the same strength specification, so the basic design of the gate can also be shared. As shown in Figure 8.7, since lean duplex stainless steel has corrosion resistance equal to or higher than that of conventional steel, application of SUS 821 L 1 to facilities in fresh water environment and SUS 323 L for brackish water environment is proposed.

Source：Overview of the duplex stainless steel（JSSC 2014, AUTUMN No.19）

Figure 8.7 Application proposal of lean duplex stainless steel

3) Achievements to flood gates

In recent years, the application of lean duplex stainless steels to domestic water gates, dams and land locks has increased.2 shows the results of application of lean duplex stainless steel to water gates in Japan, and Figure 8.8 shows an example of a flood gate that applied lean duplex stainless steel. To the extent studied by the study team, there are no application records in other countries.

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These are the results of evaluation of high corrosion resistance and high strength of lean duplex stainless steel, and it can be said that the application of lean duplex stainless steel to the flood gate is an excellent Japanese technology not found in other countries. Lean duplex stainless steel is an internationally certified material also registered in ASTM, but considering the application to flood gates and weirs, Japanese companies are technically superior and the possibility of orders is high.

Table 8.2 Results of application of lean duplex stainless steel to water gates in Japan

Construction name location Grade Equipment Yuriage drainage plant gate facility Miyagi Pref. SUS323L Gate Terano drainage plant dust removal facility Miyagi Pref. SUS323L Screen Ainokama drainage plant dust removal facility Miyagi Pref. SUS323L Screen Takasago drainage plant Miyagi Pref. SUS323L Screen Minamiku drainage plant dust removal facility Miyagi Pref. SUS323L Screen Oomuta drainage plant gate facility Fukuoka Pref. SUS323L Gate Tomkikawa flood gate Hokkaido SUS821L1 Gate Tukihama No.2 flood gate Miyagi Pref. SUS323L Gate Kamaya flood gate Miyagi Pref. SUS323L Gate Funakoshi drainage plant gate facility Miyagi Pref. SUS323L Screen Kawai flood gate Niigata Pref. SUS821L1 Gate Nanasegawa flood gate Wakayama Pref. SUS323L Guide rail Yaguchigawa drainage plant dust removal facility Hiroshima Pref. SUS821L1 Dust removal Kakouzeki fish gate Fukuoka Pref. SUS323L Gate Miyatagawa flood gate Miyazaki Pref. SUS323L Gate guide Kosode fishing port flood gate Iwate Pref. SUS821L1 Gate Kurikoma dum water intake Miyagi Pref. SUS323L Water intake Ootuka flood gate Miyagi Pref. SUS323L Gate Tatekawa flood gate Tokyo SUS323L Gate Shinonagigawa flood gate Tokyo SUS323L Gate Kiyosumi drainage plant gate facility Tokyo SUS323L Gate Onagigawa drainage plant gate facility Tokyo SUS323L Gate Kagasuno bridge Tokushima Pref. SUS821L1 Guide rail Sakaigawa flood gate Chiba Pref. SUS323L Gate Source: The Study Team

Nippon Koei Co., Ltd. 8-9 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Advantage of Technology and Other Aspects Main Report of Japanese Companies Chapter 8

Source: The Study Team

Figure 8.8 Example of a flood gate that applied lean duplex stainless steel

8.2 Description and Costs of Main Equipment and Materials Expected to Be Procured from Japan

8.2.1 Technologies for the reconstruction and increase in dam capacities

In the Project for the Reconstruction and the Increase in the Capacity of the Bohol Island Irrigation Dam Group, proposed as part of this research, which comprises new construction of a hydraulic power station, replacement of the dam spillway (with a gate), and establishment of an operation monitoring system, the main equipment expected to be procured from Japan are as follows:

 Application of new materials to replacing the spillway with a gate;  Technologies for countermeasures against sediment; and  An operation and management monitoring system.

Application of new materials to replacing the spillway with a gate

The contents expected to be procured from Japan in the replacement of the spillway with a gate are shown in the table below. The cost is estimated at about 1,000,000 PHP/unit area of a gate in m2 taking into consideration the procurement situations in the Philippines.

Table 8.3 Equipment and materials expected to be procured from Japan

Structure Item Description

Lock and weir Fabrication and  Materials for opening-and-closing equipment installation of a gate  Materials for a gate body (Lean duplex phase stainless body steel)  Technical supervision by a gate maker (design and

Nippon Koei Co., Ltd. 8-10 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Advantage of Technology and Other Aspects Main Report of Japanese Companies Chapter 8

fabrication of a gate body and supervision of the installation of the gate body, gate stoppers and opening- and-closing equipment) Source: The Study Team

Technologies for countermeasures against sediment

One of the technologies that can be procured from Japan as countermeasures against sediment is the sediment discharging method using the difference in water levels. The actual performance records of the method implemented in the research on the sediment countermeasure for the Wonogiri Dam in Indonesia are:

Facility cost: about 50,000,000 yen (for a verification test); and

In order to apply the system to the project in the Philippines, it is necessary to examine the applicability of the technology and conduct detailed design, estimate costs and conduct a verification test in the full- scale research in the future.

Operation and management monitoring system

The cost for improvement of irrigation telemeter system is estimate as below:

i) Improvement of Malinao irrigation scheme: 21,540,000yen, ii) Improvement of Bayongan irrigation scheme: 16,890,000yen iii) Operational maintenance cost: 1.34 million yen (Bohol irrigation district system as a whole)

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8.3 Policies Necessary for Promoting Japanese Companies' Getting Orders

8.3.1 Technologies for Restoration and Upgrading of Dams

Technical assistance for restoration and upgrading dams under operation

This research confirms that several existing dams are in need of reconstruction and capacity increase. In contrast, while individual dams have undergone reconstruction and capacity increases in the Philippines, no technologies have been developed to systematically implement dam reconstruction projects. For example, there have been the cases where the irrigation dams under the jurisdiction of the NIA have lost their water storage function due to the progress of sedimentation. Thus, there are immediate needs for applying the dam reconstruction technologies established in Japan to the dams in the Philippines.

Also, the Philippines still has many issues in terms of deficiency in recording and keeping operation and management information and of a shortage of engineers with expertise in reconstruction and increasing the capacity of dams. In order to promote Japanese companies' getting orders in the related fields in the future, it is of primary importance to improve the level of local engineers' understanding of elemental technologies while acquiring basic references and information necessary for formulating dam reconstruction plans, systematizing dam reconstruction technologies, and establishing standards.

In the course of implementing the above measures, it is also important to establish policies to identify Japanese technologies necessary for and applicable to projects in the Philippines by thoroughly reviewing past dam reconstruction projects and to encourage the participation of skilled Japanese companies in future projects. To this end, it is desirable to implement and reinforce the technical assistance of the following items:

1) Establishment and renewal of a unified database on existing dams  Organization and update of the management ledgers of dam facilities  Establishment of an operation information database on dams and related facilities  Implementation of regular and accurate bathymetric surveys and quantification as well as monitoring of sediment in reservoirs 2) Establishment and reinforcement of the operation procedure and maintenance manuals of dam facilities 3) Implementation of risk assessments with respect to the stability of dam spillways and dam bodies 4) Introduction of dam operation and management systems and transfer of skills to use them 5) Transfer of dam reconstruction technologies (raising dam heights, providing penetration holes in dam bodies, renovation of spillways and water intakes, and countermeasures against sediment)

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8.3.2 Application of Mew Materials

Technical assistance in applying lean duplex phase stainless steel to locks

Duplex phase stainless steel has been used internationally and its market size in 2016 was estimated at 2.7 billion US$. The market is expected to expand to 3.4 billion US$ in 2021 with an annual average growth rate of 4.7%.3

Also, that same report lists 15 companies from around the world as major manufacturers of duplex phase stainless steel. Although 3 Japanese companies are included in the list, they have been facing severe international competition so it can hardly be said that Japanese companies have a monopoly in the international market.

Considering the prices of commodities and labor in Japan, it is difficult for these Japanese companies to compete against overseas manufacturers that have an overwhelming share in the international stainless steel market on the price of general steel. Thus, special stainless steel that is not price competitive but excellent in durability is expected to meet clients' needs for increasing durability of products while using less stainless alloy elements than conventional ones.

In fact, Japan is among the first to focus its attention on the durability of stainless steel and apply it to social infrastructure development, particularly river structure development. As part of the promotion of stainless steel utilization, lean duplex phase stainless steel, which has higher strength, hardness and corrosion resistance than conventional stainless steel (SUS304 or SUS316L) used for river facilities such as dams, weirs, locks and drainage pump stations, was registered on the new technology information system (NETIS) of the Ministry of Land, Infrastructure, Transport and Tourism in November 2012 for promoting its application to social infrastructure development. Taking advantage of the experience gained in actual applications, a patent has been filed for lean duplex phase stainless steel excellent in corrosion resistance and ductility at welding temperatures (Patent application No. 2009- 542284) with the intention of applying the material to welded sections, which are particularly important for quality management. Thus, based on these experiences, it is expected that Japanese technical assistance will focus on the application of lean duplex phase stainless steel to locks.

Also, the research team offered its opinion that, "It is not good enough just to purchase duplex phase stainless steel materials, but importance must be placed on quality control at construction sites," to the DPWH, the counterpart organization, and the MMDA, the organization in charge of the management of facilities. The important thing is to achieve the Philippine government's understanding of the necessity

3 Duplex Stainless Steel Market by Grade (Duplex, Lean Duplex, Super Duplex), Product Form (Tubes, Pumps & Valves, Fittings &

Flanges, Welding Wires), End-Use Industry (Oil & Gas, Desalination, Chemical, Pulp & Paper), Region - Global Forecast to 2021）

Nippon Koei Co., Ltd. 8-13 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Advantage of Technology and Other Aspects Main Report of Japanese Companies Chapter 8 of adopting lean duplex phase stainless steel, not simply as a new material, but as a material with excellent on-site quality control by Japanese companies.

In the Philippines, the DPWH revised its design standards entitled the "Design Guidelines, Criteria and Standards" in 2015 and the concept of life cycle cost was introduced in Vol.6 Value Engineering of the revised design standards. However, the concept has not been well understood in the Philippines and there have been few deliberations to materialize the concept. Therefore, it is also necessary to extend technical assistance in the reduction of life cycle costs in a practical implementation phase.

Based on the above, it is desirable that the technical and economic advantages of applying lean duplex phase stainless steel to locks, as is done in Japan, be widely understood by all the personnel in the Philippine organizations, including those in charge of the project, through technical assistance throughout the course of the development aid in the practical implementation stage and seminars for the DPWH and the MMDA. It is also desirable that the project be implemented under a yen-loan scheme so as to encourage proactive participation of Japanese gate and material manufacturers in the practical implementation stage.

Information provision on the preparation for pre-qualifications and international tenders

It is important that the feasibility study following this research be spearheaded by Japan so as to prepare an environment that enables Japanese companies to display their technical capabilities and experience in a manner that incorporates Japanese technical standards into the pre-qualification and specifications of the project. It is also desirable to lobby the Philippine organizations to apply requirements in which Japanese companies can be rated sufficiently high to the specifications for lock construction work and the criteria to select a consultant and a contractor, and to evaluate and examine suitable equipment and materials to be used in the project on the basis of the performance code requiring new technologies, quality control and cost reduction in which Japanese technologies can have advantages.

In particular, the selection of a consultant for detailed design is important because the prequalification criteria and specification requirements are generally prepared by the consultant. It is also important to provide the Philippine organizations with information on the superiority and economic advantage of Japanese technologies so as to lobby them to select a Japanese consultant for the feasibility study following this research in the case of the project implementation under the yen-loan scheme, or for the detailed design in the case of the project implementation on the budget of the Philippine government.

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CHAPTER 9 APPLICABLE FUND SOURCE

In this chapter, the applicable fund source for the rehabilitation project of existing dams is evaluated. In sub-chapter 9.1, applicable business schemes depending on the kind of implementing entities are explained. In the sub-chapter 9.2, outline and conditions of each fund source is described.

9.1 Applicable Project Scheme

9.1.1 Rehabilitation of Existing Dams owned by NIA (example: Lupao Dam in Ruzon)

The applicable project scheme to the existing dams owned by NIA is shown below. The dams are operated and owned by NIA, hence the use of ODA loan provided by concessional conditions is expected for the project. The budget for construction and procurement would be provided from the government by sub-lent or subsidy through DA.

Figure 9.1 Project Scheme for Rehabilitation of Existing Dams owned by NIA

9.1.2 Construction of Small Scale Hydro Power Generation Project (example: Malinao, Bayongan, Capayas Dams in Bohol)

Project scheme of small scale hydro power generation system in Bohol island is shown below.

Japanese and local investors create SPC for the project. Generated electricity by the hydro power generation system is sold to ECs (Electric Cooperatives) which distribute electricity to users. The sold unit tariff is determined by applying the FIT (Feed-In Tariff) or the rate which is mutually agreed between SPC and EC.

The project could be financed by loan and equity. The loan part is lent by the local banks and international banks such as JICA/JBIC which provide under concessional conditions. The equity is invested by local and Japanese investors. In addition, there is a possibility that 50% of equipment cost (at maximum) is subsidized by JCM framework to promote reduction of greenhouse gas emission supported by the Japanese MOE.

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Figure 9.2 Project Scheme for Construction of Small Scale Hydro Power Generation System in Bohol Island

9.1.3 Rehabilitation of Existing Dams owned by Private Companies (example: Ambuklao and Binga Dam in Ruzon)

The fund source used for the existing dams which are owned and operated by private companies is limited to Two Stem Loan provided by JICA and JBIC. The rest of the fund is provided by the loans from commercial banks. The Japanese construction companies and material/machine companies could participate in the project for the purpose of construction and procurement.

Figure 9.3 Project Scheme for Rehabilitation of Existing Dams owned by Private Companies

Nippon Koei Co., Ltd. 9-2 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Applicable Fund Source Main Report Chapter 9

9.2 Expected Fund Source of the Project

To implement the project, funding with lower financial cost, such as concessional loans provided by JICA or JBIC, is expected. The outline of applicable fund source is summarized based on interviews to stakeholders and reviews of past similar projects and studies.

Table 9.1 Expected Fund Source

Type of Project Implementing Providing Institute Fund Source Entity Public JICA ODA Loan Organization Private Entity JICA Private Sector Investment Finance (PSIF) Loan Environment Development Project (EDP, Two Step loan) JBIC Global action for Reconciling Economic growth and Environmental preservation (GREEN) Other Two Step Loan Ministry of Joint Crediting Mechanism (JCM) Environment (MOE)

9.2.1 Applicable Fund Source for the Project implemented by Public Organizations

JICA ODA Loan

It is a Concessional loan which the public organizations could accept from JICA in Japanese Yen.

According to JICA’s classification, the Philippines is categorized into Lower-Middle Income Countries as of October 2018, and the terms and conditions of the loan is determined as follows;

General Terms: Repayment period 15 - 40 years, Grace period 5 - 12 years, Interest rate 0.85 - 1.45% (Fixed Rate)

Preferential Terms: Repayment period 15 - 40 years, Grace period 5 - 12 years, Interest rate 0.65 - 1.25% (Fixed Rate)

STEP: Repayment period 40 years, Grace period 12 years, Interest rate 0.10% (Fixed Rate)

In case of this study, the rehabilitation projects of existing dams owned by NIA could be appropriate projects for ODA loan. In contrast, the existing dams once owned by NPC, was mainly owned and operated by private entities at present, and the ODA loan could not be provided.

9.2.2 Applicable Fund Source for the Project implemented by Private Entities

JICA, Private Sector Investment Finance (PSIF) Loan

PSIF is the loan provided to infrastructure project implemented by private entities. Target projects are in infrastructure sectors of electricity, transportation, water supply and sanitation, solid waste, information, health, education, etc. Also, the projects of countermeasures of climate change such as

Nippon Koei Co., Ltd. 9-3 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Applicable Fund Source Main Report Chapter 9 forestry, disaster mitigation, energy saving, reduction of pollution are included as the target. Repayment period is approximately 20 years including 5 years of grace period. The currency is in Japanese Yen or PHP. Terms and conditions of the loan is determined based on the credibility of borrower and financial viability of the project.

JICA, Environment Development Project (EDP, Two Step loan)

EDP is the two step loan originally funded by ODA loan through the Development Bank of the Philippines (DBP). The loan is provided to the projects in infrastructure sectors of water supply and sanitation, solid waste and renewable energy. Borrowers are either public entities, LGU (Local Government Unit), government owned and controlled corporations (GOCC), water district and cooperatives.

The total loan amount of approximately JPY 24.8 billion signed in 2008 was disbursed, and the second phase is planned. If the loan for second phase is ready, the project which is implemented by private entities could be funded by this loan with low financial cost. For first phase, repayment period was 3 to 20 years, and the grace period was 5 years or shorter. Currency was in PHP.

JBIC, Global action for Reconciling Economic growth and Environmental preservation (GREEN)

JBIC supports projects aiming at preserving the global environment by providing equity, loan and guarantee called “GREEN”, which is an abbreviation of Global action for Reconciling Economic growth and ENvironmental preservation. The sectors of past projects are solar power generation with high environmental technology, construction of power plant with efficient energy use, introduction of facilities with lower energy consumption, etc.

In the Philippines, as using GREEN scheme, loan of USD 25 million was provided to BDO Unibank, Inc. which will be lent to renewable energy projects. The currency of the loan could be in PHP.

The use of such loan is expected for the projects of small scale hydro power generation evaluated in this study.

JBIC, Other Two Step Loan

In case there is other kind of two step loan eligible for the project implemented by private entities, the loan condition and availability will be considered.

Ministry of the Environment (MOE) of Japan, Joint Crediting Mechanism (JCM)

The scope of the financing includes facilities, equipment, and vehicles which reduce CO2 from fossil fuel combustion as well as construction cost for installing those facilities on the premise of delivering the issued JCM credits to the government of Japan.

Regarding to the Homepage of Global Environment Centre Foundation, there are 17 JCM partner countries including the Philippines as of August, 2018. The memorandum of cooperation between Japan and Philippines was signed in January, 2017. Through this model, 50% at maximum of initial investment

Nippon Koei Co., Ltd. 9-4 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Applicable Fund Source Main Report Chapter 9 cost could be subsidized by the Japanese MOE. Already, 3 projects were approved in small-scale hydro power generation sector in the Philippines. The maximum subsidy amount out of initial investment cost is set at 30% for the same sector project in each country. Use of the subsidy is expected for priority projects in this study in Bohol.

9.2.3 Other Incentives from the Government of the Philippines

The first integrated law for renewable energy in whole south east Asian region was enacted in the Philippines in October 2008, which was Renewable Energy Act.

The main purposes of this act are “1) accelerating the development of renewable energy, “2) development of national and local capabilities in the use of renewable energy systems” and “3) economic growth and development with the protection of environment”.

In the act, Renewable Portfolio Standard (RPS) and FIT (Feed-in Tariff) system are also integrated.

Public Support of the Renewable Energy Act (RA9513)

Enacted in 2008 to accelerate the development of renewable energy. The National Renewable Energy Board (NREB) is created to monitor the issues of environment and energy. The following Incentives are provided for use of renewable energy.

 Income Tax Holiday: Exemption from corporate income tax for 7 years after the start of operations. If further investment is performed (expansion, increase in main machinery etc.) then further exemption of up to 7 years x 2 can be authorized (a maximum of 21 years).  Reduction of Corporate Income Tax: Reduction of corporate income tax to 10% from the 8th year of operations onward (usually 32%).  Exemption of Taxes Related to Importing Materials and the Sale, Transfer and Disposal of Asset Facilities: After receiving business authorization from DOE, exemption for 10 years on taxes relating to importing all asset materials related to the project. Also exempt from taxes relating to the sale, transfer or disposal of asset facilities.  Reduction of Real Estate Tax: Reduction of tax on land used for the placement of machinery to 1.5% or less of the acquisition cost or the book value.  Preferential Policy for Accounting: Being in the red for the first 3 years of operation is deducted from profits over the next 7 years. However, deduction from profits is not made as an initial adjustment, but only applies when the operation itself is in the red.  Acceleration of Depreciation: If no preferential treatment such as a reduction of corporate income tax was received prior to starting operation, special measures that accelerate depreciation can be used. (however, once these measures are used a reduction of corporate income tax cannot then be received)  Exemption from Value Added Tax: Exemption from Value Added Tax (VAT) on the sale of fuel and power.

Nippon Koei Co., Ltd. 9-5 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Applicable Fund Source Main Report Chapter 9

 Emission Rights: Exemption from taxes relating to purchase and sale of emission rights.  Preferential Treatment for Special Electrification Regions: Those establishing new business in target regions for electrification receive 50% of standard power charges paid in cash.  Tax Exemption Measures for Domestic Transactions: Exemption of VAT and import taxes on machinery and services on domestic business-related transactions.  (Source: Feasibility study on WAWA river mini-hydro power project in the province of Agusan del Sur, final report , Table 1-11）

FIT (Feed in Tariff)

In order to promote the renewable energy generation, FIT system was started by Energy Regulation Commission (ERC). Introduction of FIT system is announced in July 2010, and Rules of Practice and Procedures (2010), guideline (2013) and sample contract (204) were published. The total period of buying electricity by FIT price is 20 years, and the price was determined in 2012 as follows;

 Solar : 9.68PHP/kWh  Wind : 8.53PHP/kWh  Hydro : 5.9PHP/kWh  Biomass : 6.63PHP/kWh

It is noted that FIT price could be changed as influenced by future forecast and price inflation.

Regarding to the interviews to ECs, application and approval of FIT system will be processed after the power plant is ready to operate. If the FIT price decreased during the construction period, the SPC needs to shoulder the burden of such risk. Therefore, determining the sales price agreed in the mutual agreement with SPC and ECs rather than by FIT price should be the priority.

Nippon Koei Co., Ltd. 9-6 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Action Plan and Issues for Project Implementation Main Report Chapter 10

CHAPTER 10 ACTION PLAN AND ISSUES FOR PROJECT IMPLEMENTATION

10.1 Actions taken to Request for Japanese ODA Project

10.1.1 Conclusion of the Study

The proposed project of “Improvement of Water Resources Management of Bohol Irrigation Dams” will contribute for redevelopment of water resources through i) the improvement of dam operation by installation of irrigation water management system and ii) the improvement of the Malinao Dam Spillway (raising of NWL by 2 m by installation of rubber gate) studied by NIA that enable to reduce the excess volume of spillway outflow under current operation. The proposed project is preliminary evaluated economically feasible and social and environmentally acceptable.

On the other hand, another proposed project of “Hydropower Provision in Bohol Irrigation System” is preliminary evaluated the financial viabilities is low because of low efficiency of power generation due to irrigation dependable water and exclusion of income increase by irrigation water development as per the present regulation in the Philippines. Full-scale feasibility study shall be implemented based on more detailed investigation for dam operation, design and financial scheme.

10.1.2 Work Shop of the Study

The workshop of the Study was heled at NIA Head Office Conference Room on February 1, 2019. The participants of the workshop were 25 in total, from NIA, Embassy of Japan, JICA Philippine Office, JICA-DPWH experts, and the Study Team.

In the Workshop, implementing agency of NIA expressed appreciation of the outcomes of the Study, and they are willing to implement the proposed projects together with the improvement of the Malinao Dam Spillway that have been studied by NIA and tender evaluation is being undertaken as of January 2019.

10.1.3 Meetings with Concerned Agencies for Endorsement of Japanese ODA

The results of the Study and necessary actions were explained and discussed with JICA Philippines Office on January 29, 2019 and with Embassy of Japan on February 7, 2019.

10.2 Action Plan and Issues for Request of Japanese ODA Project in Future and Horizontal Development to Other Countries

10.2.1 Action Plan and Issues for Request of Japanese ODA Project in Future

Implementation of Full-Scale Feasibility Study:

Financial viability of provision of small hydropower station at Diversion Chute is xxx. Full-scale feasibility study shall be implemented based on more detailed investigation for dam operation, design and financial scheme.

Nippon Koei Co., Ltd. 10-1 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Action Plan and Issues for Project Implementation Main Report Chapter 10

Immediate Installation of Telemetric Irrigation Management System:

Telemetric irrigation management system is recommended to be installed at the same time of implementation of the spillway improvement of the Malinao Dam. It will improve water use operation for irrigation and proposed hydropower generation.

Monitoring of Reservoir Sedimentation and Implementation of Countermeasures for Sedimentation

Countermeasures for reservoir sedimentation in Malinao Dam shall be implemented. So far no detailed reservoir sediment survey has been conducted. It is recommended to conduct periodical reservoir sedimentation survey. Some possible measures are i) construction of sediment flushing gate to sustain the active storage, and ii) removal of sediment depositions surrounding area of intake to protect from clogging of the intake. It is recommended to conduct the study for adaptation of the Japanese advance technologies such as construction methods, operation and maintenance monitoring system and sediment survey to extend reservoir life and to reduce operation and maintenance cost.

Others

Though the project cost is not so large and the policy of the Governments of the Philippines is tend to apply only the STEP for the Japanese ODA Loan at present, it is not considered applicable for the Japanese ODA Loan with only this project. There are some ideas to apply sector loan including several similar projects in the Philippines and/or to apply 2 step loan.

The dams in Mindanao were not selected as the candidate projects taking into account the present safety issues. However, there are some dams having high potential needs for restoration and upgrading dams. If the safety issues is settled down in the future, these dams will be taken up for the feasibility study.

10.2.2 Horizontal Development to Other Countries

At present, the upgrading dams under operation is the hot topic in the world at present due to the progress of reservoir sedimentation and dam aging. International Commission of Large Dam (ICOLD)

The technology for the upgrading dams under operation is expected to be horizontally developed to other countries, particularly to South-East and South Asian Countries because of following backgrounds and reasons:  Having similarity of climate and hydro-meteorology, and having similar characteristics of flood, required dam operation and reservoir sedimentation situations,  Strong needs for restoration and upgrading of dams under operation due to increase of water demand with the high rate of the economic developments,  Necessity of the integrated technical standards and guideline for restoration and upgrading dams because many existing dams were constructed adopted the local standard and/or different criteria of different donors,

Nippon Koei Co., Ltd. 10-2 The Study for Restoration and Upgrading Dams Under Operation in the Philippines Draft Final Report Action Plan and Issues for Project Implementation Main Report Chapter 10

 Difficulty of developments of new dams because of social and environmental problems. The upgrading of existing dam would mitigate such adverse impacts since it would be implemented within the existing Right-of-Way.

Nippon Koei Co., Ltd. 10-3 The Study for Restoration and Upgrading Dams Under Operation in the Philippines

Attachment

Attachment 1. Location Map of Existing Dam and Hydro Power Plant Attachment 1 Attachment 2. List of Existing Dam and Hydro Power Plant Location Dam

Operator of Type of Constructio Purpose of Reservoir Reservoir No. Name of Dam Owner Power Power Type of Crest gross usable n Year Dams Island River Height(m) Station Station Dam Length (m) storage storage (MCM) (MCM)

NPC Non- NPC-01 Ambukulao 1956 SNAPBI H Dam Luzon Agno ER 129.00 452.00 327.00 258.00 NPC/IPP Non- NPC-02 Binga 1960 SNAPBI H Dam Luzon Agno ER 107.40 215.00 87.40 48.00 NPC/IPP Non- NPC-03 San Roque 2003 SNAPBI H,I,S,F Dam Luzon Agno ER 200.00 1130.00 850.00 NPC/IPP Non- NPC-04 Angat 1967 AHC H,I,S,F Dam Luzon Angat ER 131.00 568.00 850.00 NPC/IPP Kalayaan Pumped NPC-05 1983 NPC CBK H Luzon Storage Luzon - Caliraya dam 1945 NPC Caliraya TE 42.00 240.00 86.00 78.00 /Laguna 1948 start Luzon - Lumot dam NPC Lumot TE 30.00 43.80 constructio /Laguna NPC NPC-06 Agus I 1992/1994 NPC H ROR Mindanao Agus - Mindanao NPC Mindanao NPC-07 Agus II 1979 NPC H ROR Agus TE 29.00 140.00 Mindanao /Lanao NPC NPC-08 Agus IV 1985 NPC H Dam Mindanao Agus ER - 247.00 Mindanao NPC NPC-09 Agus V 1985 NPC H ROR Mindanao Agus - - Mindanao NPC NPC-10 Agus VI 1953-1971 NPC H Dam Mindanao Agus ER 12.50 67.00 Mindanao NPC NPC-11 Agus VII 1983 NPC H Dam Mindanao Agus CG 173.60 288.00 Mindanao NPC NPC-12 Pulangi IV 1986 NPC H Dam Mindanao Pulangi ER 11 - 17 1070.00 Mindanao (Other Source) CBK Power Luzon Pagsanja Concrete NPC-13 Botocan 1948 NPC H ROR 30.48 70.1 Company /Laguna n gravity Luzon Lake NPC-14 Buhi Barit 1957 NPC H ROR -- /Camarin Buhi Luzon NPC-15 Cawayan 1959 NPC H ROR Cawayan -- /Sorsogo Sta. Clara Overflow Head NPC-16 Loboc 1955 NPC H ROR Bohol Loboc Power concrete =11.1m Sta. Clara Overflow NPC-17 Amlan 1958 NPC H ROR Negros Amlan Power concrete NPC-18 Talomo 1950 NPC H

NPC-19 Tudaya no info NPC H

*SNAPBI (SN Aboitiz Power Benguet, Inc.), SRPC(San Roque Power Corporation), AHC(Angat Hydro Corporation), CBKPC (CBK Power Company Ltd.)

Attachment 2 NIA (Multi Purpose Dam) Dam NIA-M01 Magat 1982 NIA SNAP Irrigation Dam Luzon Magat 114.00 4160.00 1,250.0 /Rockfill Pampang Dam NIA-02 Pantabangan 1974 NIA First Gen Irrigation Dam Luzon 107.00 1615.00 2,996.0 a /Earthfill NIA (Irrigation Dam/SRIP)

NIA-S01 Acop NIA None I None Luzon 12.50

NIA-S02 Lupao 1994 NIA None I None Luzon 27.00

NIA-S03 Tanguilad NIA None I None Luzon 28.50

NIA-S04 Aulo NIA None I None Luzon 30.00

NIA-S05 Alapasco 1995 NIA None I None Iloilo 21.00

NIA-S06 Ilaya NIA None I None Bohol 25.00

NIA-S07 Capayas NIA None I None Bohol 17.00

NIA-S08 Calango 1995 NIA None I None Negros 26.00

NIA-S09 Nasig-Id NIA None I None Negros 32.00

NIA-S10 Talibon NIA None I None Bohol 21.50

NIA-S11 Miral 1994 NIA None I None Mindanao 27.00

NIA-S12 San Angel NIA None I None Luzon 21.50

NIA-S13 Masidem NIA None I None Luzon 27.00

NIA-S14 Tangub NIA None I None Mindanao 32.25

NIA-S15 Kitcharao NIA None I None Mindanao 29.00

NIA-S16 Can-Asujan NIA None I None Cebu 25.00

NIA-S17 Dauin NIA None I None Negros 29.00

NIA-S18 Binalawan NIA None I None Negros 16.00

NIA (Irrigation Dam) Casecna Diversion NIA-I01 Casecnan 2002 NIA NPC/IPP I, H None Luzon -- n dam Non- Pampang NIA-I02 Masiway 1981 NIA I, H None Luzon Dam 25.00 6.00 NPC/IPP a Luzon NIA-I03 Canili /Diayo Dam 1981 NIA None - None Canili - -- /Aurora Malinao Dam NIA-I04 1998 NIA None I None Bohol Wahing 20.40 845.00 (Bohol I) Filltype Bayongan Dam NIA-I05 2007 NIA None I None Bohol - 35.50 855.00 (Bohol II) Earthfill Capayas NIA-I06 1992 NIA None I None Bohol (Bohol II) NWSS Weir NWSS-01 Bustos 1926 - I Luzon Angat /Rubber? Dam NWSS-02 Ipo 1984 - S Luzon Angat /Concrete Earth NWSS-03 La Mesa 1929 - S Luzon Tullahan 33.00 51.00 Dam Others 19th Gravit y O-01 Prinza (Molino) I Luzon Zapote 10.00 450.00 Century Dam around Metro Cebu O-02 Buhisan dam S Cebu Dam 1912 District O-03 Agusan Dam 1957 H Mindanao Agusan Weir 1.00 22.00 Mindanao Gravit y O-04 Aragon Dam 2014 Hector I Cateel 5.50 /Davao Dam Dam O-05 Cabulig 2012 MINERGY H Mindanao Claveria 38.00 Concrete

Attachment 2

Attachment 3. Photos of Dams

(https://alchetron.com/Magat-Dam) (http://wikimapia.org/4155300/Magat-Dam) Magat Dam (LUZON, Alfonso Lista) H=114m, Capacity: 360 MW. Constructed in 1982, Dam: National Irrigation Administration (NIA) jurisdiction、Hydropower Plant: SN Aboitiz Power-Magat, Inc. (SNAP-Magat) operation

(http://www.cityofpines.com/ambuklao.html) (https://en.wikipedia.org/wiki/Ambuklao_Dam) Ambukulao Dam (LUZON, Benguet) H=129m, Capacity: 115MW. Constructed in 1956, National Power Corporation (NPC) jurisdiction, SN Aboitiz operation

(http://www.cityofpines.com/binga.html) (https://rusa4.wordpress.com/tag/binga-dam/) Binga Dam (LUZON, Benguet) H=107m, Capacity:140MW. Constructed in 1960, National Power Corporation (NPC) jurisdiction、SN Aboitis operation

Attachment 3

(http://sanroquepower.ph/) (http://newsinfo.inquirer.net/319109/ farmers-to-get-less-irrigation-water-from-dam) San Roque Dam (LUZON, Pangasinan H=200m, Capacity:435 MW. Constructed in 2003 under San Roque Multipurpose Project (SRMP)

(http://bworldonline.com/content.php?section=Economy&title= (https://sg.news.yahoo.com/tribal-folk-seek- doj-clears-nia-buyout-of-casecnan-hydro-plant&id=122693) share-casecnan-000000300.html) Casecnan Dam H= - m, Capacity: 140 MW. Constructed in 2002, National Irrigation Administration (NIA) jurisdiction

(https://www.energyworldmag.com/romania-charge-daffaires- mihai-sion-part-of-eu-visit-to-the-philippines-regarding-renewable (https://www.pinterest.jp/pin/290482244690156144/) -energy/pantabangan-dam/) H=107m, Capacity: 120 MW. Constructed in 1974, National Irrigation Administration (NIA) jurisdiction

Attachment 3

(http://politics.com.ph/repair-of-aging-angat-dam-now- (http://mwss.gov.ph/projects/angat-dam-and-dyke- underway--guv-says/) strengthening-project-addsp/) H=131m, Capacity:256MW. Constructed in 1967, National Power Corporation (NPC) jurisdiction

Calilaya Dam (LUZON, Laguna) H=22m, Capacity: 22.6 MW. Constructed in 1942, Penstock, Power Plant and other equipment was rehabilitated by CBK PCL in 2002

(http://www.tripmondo.com/philippines /calabarzon/botocan/) (https://www.flickr.com/photos/gilbertrondilla/10035678973 _) Botocan Dam H=46m, Capacity: 21MW. Constructed in 1948, National Power Corporation (NPC) jurisdiction, owned by Manila Electric Company (Meralco) before 1979

Attachment 3

(https://www.napocor.gov.ph/NPCDams/index.php (http://www.kagay-an.com/new-pulangi-dam-pushed-for /our-dams/pulangi-iv-hydroelectric-plant) -public-private-partnership/) Pulangi Dam (Pulangi Ⅳ) H=115m, Capacity: 255MW. Constructed in 1986, National Power Corporation (NPC) jurisdiction

(http://www.boholchronicle.com.ph/2016/06/07/malinao-set-for -irrigation-2-dams-water-not-operational-level/) (https://www.flickr.com/photos/ricephotos/4007745085 ) Malinao Dam (Bohol Ⅰ) H=35.5m Constructed in 1992, National Irrigation Administration (NIA) jurisdiction

Bayongan Dam (Bohol Ⅱ) H=35.5m Constructed in 1997, National Irrigation Administration (NIA) jurisdiction

Attachment 3

Capayas Dam (Bohol Ⅱ) H= - m Constructed in 1992, National Irrigation Administration (NIA) jurisdiction

(https://ja.foursquare.com/v/miral-river-earthfill-dam/ (https://www.trendsmap.com/twitter/tweet/976379583741112320) 50f8dcdce4b00640b1e5d979) Miral Dam (Mindanao) H=27m Constructed in 1994, National Irrigation Administration (NIA) jurisdiction

Tangilad Dam (Luzon) H=28.5m Constructed in 2001, National Irrigation Administration (NIA) jurisdiction

Attachment 3

Lupao Dam (Luzon) H=27.0m Constructed in 1994, National Irrigation Administration (NIA) jurisdiction

Attachment 3

Attachment 4. Endorsement Letter from NIA Attachment 4

Attachment 6. Questionnaire and Answers

The Study for Restoration and Upgrading Dams Under Operation in the Republic of the Philippines

Questionnaire Sheet for Upgrading Dam Under Operation

Attachment 6 Questionnaire for Sedimentation and Watershed Management (Some items are filled, subject to revise based on your latest data)

1. General Information

1.1 Name ( ) 1.2 Age ( ) 1.3 Sex (male/female) 1.4 Name of Organization/Agency ( ) 1.5 Position ( ) 1.6 Experience year of the position ( ) 1.7 Main tasks of your position ( ) ( ) ( ) ( ) ( )

Q - 1

Attachment 6 2. Data/Information of Dams and Hydropower Stations under operations

2.1 The number of dams (H>15m) under operations ( ) 2.2 The number of hydropower stations attached with the dams (H>15m) ( ) 2.3 O&M Organization ( ) 2.4 Site safety of existing dams in case of proposed project implementation ( ) 2.5 Please provide following data and information a. List and general information of dams and hydropower stations, if any. b. O&M budget data recent 10-years. c. O&M manual, if any.

3. Current issues of dam operation and damaged on the facilities 3.1 Please line up the dams which have following issues, if any a. Dams suffering from reservoir sedimentation ( ) b. Dams suffering from aging/deterioration or damaged on related facilities and apparatus. ( ) c. Dams which have operation and maintenance issues ( ) d. Dams which have social and environmental issues ( )

3.2 What are the current main issues of the dam operation? Please select from the following list (you can select multiple item)

a. Aging of dam main body b. Deficit of spillway capacity for flood control c. Frequent spill out d. Land slide and slope failure in surrounding area of reservoir e. Reservoir sedimentation f. Blockage of intake and inlet (by garbage and sediment depositions) g. Blockage of tailrace and outlet (by garbage, sedimentation, back water)

Q - 2

Attachment 6 h. Aging/Deterioration of gate and valve i. Aging/Deterioration of waterway, penstock and tunnel j. Aging/Deterioration of turbine and generator k. Aging/Deterioration of operation system (gate, turbine, genelator) l. Aging/Deterioration of monitoring devices (dam safety, hydro-meteorology, surveillance camera, etc.) m. Deficit of maintenance flow in the downstream channels n. Social issues (land acquisition and resettlement, in case of project implementation) o. Environmental issues (in case of project implementation) p. Others ( )

4. Reservoir Sedimentation 4.1 For the dams suffering from reservoir sedimentation, when and how many times did you carry out sediment or bathymetric survey? If YES, please provide survey or bathymetric results.

4.2 Please briefly explain land use conditions and management activities in the catchment area.

5. Plan/Project of Rehabilitation and Improvement Works 5.1 Do you execute rehabilitation and improvement works? If YES, please explain what kind of works is applied, for example, replacement of intake gate, reservoir dredging, etc.

End of Documents

Q - 3

Attachment 6 1. General 2. Data/Information of Dams and Hydropower Stations under operations

1.1 1.2 1.3 1.4 1.5 1.6 1.7 2.1 2.2 2.3 2.4 2.5

Name of Dam or HP Reply The number of Site safety of Plant Name of The number of hydropower existing dams in Please provide Experience year of O&M Name Age Sex Organization/Age Position Main tasks of your position dams (H>15m) stations attached case of proposed following data and the position Organization ncy under operations with the dams project information (H>15m) implementation

NIA DAMS

Malinao No ------provided (Bohol I)

Bayongan No ------provided (Bohol II)

Capayas No ------provided

Talibon No ------provided

Kristian Jay D. NIA - UPRIIS 1(MACANAE/LU Macanae/Lupao Yes 32 M HYDROLOGIST 6 Years - N/A - - - Galapon DIVISION I PAO)

Conduct inspection and monitoring of CIS/NIS operation SENIOR and maintenance performance and Miral Yes GIL G. VALDEZ 54 M NIA 3 Years ----- ENGINEER A assess needs for planning purposes and ISF/amortization collection;

Tangilad No ------provided

NIA, Negros NESTOR M. Manage/Supervise different Calango Yes 62 M Oriental Satellite Head of NOSO 7 Years - - - - provided PASTOR activities of NOSO Office (NOSO)

Magat No ------provided

Dams NPC DAMS Sep. 4 Management ------12 Department

Dams, Reservoirs To operate and maintain for and in and Waterways behalf of PSALM Corporation the Management 981 MW Agus and Pulangi Dams, Reservoirs Division hydropower plants in Mindanao. and Waterways Sep. 4 Operations -- - - -Apart from operating the power 6 - provided Management Planning plants, NPC also implements Division Department various work orders to enhance Mindanao the power plants' capabilities in Generation power generation.

Ambuklao ------provided

Binga ------provided

San Roque ------provided

Angat ------provided

Caliraya ------provided

Agus 1 Yes ------

Agus 2 Yes ------provided

Agus 4 Yes ------provided

Agus 5 Yes ------

Agus 6 Yes ------provided

Agus 7 Yes ------provided

Pulangi 4 Yes ------provided

Attachment 6 3. Current issues of dam operation and 5. Plan/Project of Rehabilitation and 4. Reservoir Sedimentation damaged on the facilities Improvement Works 3.1 4.1 4.2 5.1 a b c d e

For the dams suffering from Name of Dam or HP Reply reservoir sedimentation, when Do you execute rehabilitation and Plant and how many times did you Please briefly explain land use improvement works? If YES, please Deficit of Landslide and Please line up the dams which have following a. Aging of dam Frequent Spill Reservoir carry out sediment or conditions and management explain what kind of works is applied, for spillway capacity slope failure in issues, if any main body out Sedimentation bathymetric survey? If YES, activities in the catchment area. example, replacement of intake gate, for flood control surrounding area please provide survey or reservoir dredging, etc. bathymetric results.

NIA DAMS

Malinao No ------(Bohol I)

Bayongan No ------(Bohol II)

Capayas No ------

Talibon No ------

Kaingin activities were observed YES, reforestation programs per Macanae/Lupao Yes LUPAO/MACANAE DAM NO YYY in the catchment area. Macanae/Lupao Dam started this month.

EIGHTY PERCENT (80%) OF MIRAL RESERVIOR FUND SILTED NOT THE CATCHMENT AREA OF OPERATIONAL AT PRESENT MIRAL RESEVOIR CONVERT Miral Yes - - Y MIRAL RESERVIOR HAVE AN TO VEGETABLE ENVIRONMENTAL ISSUES. PRODUCTION IT IS THE CAUSES OF SILTATION.

Tangilad No ------

CALANGO SRIS - Silted and deposited with large volume of sediments and debris, level of sediments 10 meters above minimum water level. Had undertaken partial (30% - Trash rack procured for installation Calango Yes Dilapidated/damaged intake trash rack made Farming activities YY 14,000 cu.m.) desilting works. On-going second time desilting works of ordinary steel. That causes clogging of the supply conduit. Most of watershed areas cultivated causing erosion/siltation problem to reservoir.

Magat No ------List of Latest Improvement Projects by DMD a. Imrovement of downstream of Caliraya The private dam operator East Dyke NPC DAMS Sep. 4 conduct bathymetric survey b. Drilling, Supply and Installation of YNNNY every 5 years Piezometers and Extensometers at Caliraya Dykes and Lumot Dam and Dyke c. Dredging of Pulangi 4 Dam Reervoir Yes. For , most of the 1. Impermeabilization of embankment areas in the eastern side are dam having piping through controlled deltas; hence, land use is more drilling & grouting. common to planting rice. 2. Corrective repair on cracked Watershed Management Division embankment (Longitudinal cracks from has implemented the Tree crest to filter chimney) with soil-cement- Sep. 4 Y - YNY Growing activities on the high bentonite slurry. lands. But as to the management 3. Installation of ebris/log booms near the of silts coming into the lake area, intake at some angle towards the we need time to refer to spillway. Watershed Management 4. Dredging of reservoir Division. 5. Repair of channel lining (rewatering within 6 hours after repair)

Ambuklao ------

Binga ------

San Roque ------

Angat ------

Caliraya ------

Agus 1 Yes

Agus 2 Yes

Agus 4 Yes Y

Y(Crest concrete Agus 5 Yes pavement cracking)

Agus 6 Yes Y

Y(concrete dam crack (for Agus 7 Yes evaluation of the uderwater section)) Sediment problem was already predicted in the 1978 Sofrelec Study, that if Pulangi 3 Dam is Y(Cracks on not constructed, all the silts will Terrace method of farming could concrete be trapped by Pulangi 4 reservoir not be implemented in the pavement at and this reduces its useful life. surrounding areas. These are Pulangi 4 Yes Y crest Y But as to the monitoring of silts private lands. Watershed (undergoing deposition into the reservoir or management is implementing investigation and silt management, we need time to Tree Growing in the areas, too. evaluation) refer to Watershed Management Division if they have the program.

Attachment 6 3.2 What are the current main issues of the dam operation? Please select from the following list (you can select multiple item)

fghijkl m n o p

Name of Dam or HP Reply Plant Aging/deteriorati Blockage of Aging/deteriorati Aging/deterorati Aging/deteriorati Deficit of Environmental Blockage of inlet on of waterway, tailrace and Aging/deteriorati on of turbine and on of operation on of monitoring maintenance flow in Social Issues issue in case of Others and intake penstock and outlet on of gate valves generator system devices the d/s channel implementation tunnel

NIA DAMS

Malinao No ------(Bohol I)

Bayongan No ------(Bohol II)

Capayas No ------

Talibon No ------

Macanae/Lupao Yes YYYY YY Y

80% of catchment area is Miral Yes planted with vegetation

Tangilad No ------

Watershed areas Calango Yes YYY Y are cultivated

Magat No ------

NPC DAMS Sep. 4 YNNNNNY N N/AN/AN/A

Y(HE Plants with removed water lilies from their forebay or reservoir and Sep. 4 YNYYYYY -trash/debris removed from -- trash racks sometimes dumped on the downstream side of the dam)

Ambuklao ------

Binga ------

San Roque ------

Angat ------

Caliraya ------

Y(alleged flooding along Agus 1 Yes Y (Tainter Gates) some coastal areas of Lake Lanao and social issues)

Agus 2 Yes Y (Tainter Gates)

Y (draft tube Trees on d/s berms Y(Tree issues on the Agus 4 Yes Y (Flap Gates) throat) & toe downstream berm & toe)

Y(No provision Y(Tree issues on the Agus 5 Yes of slot guide for downstream slope of power stoplogs)) channel right embankment Y(vertical lift Agus 6 Yes Y(blow off pipe) spillway gates)

Y(spillway gates Agus 7 Yes operability)

Y(downstream Y(Tree issuesat the upstream draiange system and downstream of dams in the (blocked by the Y(Ruts on crest reservoirs, at the downstream construction of Pulangi 4 Yes of power Y (social issues) slope of the right embankment embankment for channel) of the power channel & at the the containment downstream slope of the dikes of dredged at the Surge Pool area) sediments))

Attachment 6

Attachment 7. Dam Operation Data

Appendix

Contents 1. Malinao ...... １ 1.1 Reservior Operation ...... １ 1.2 Duration Curve ...... ３ 1.3 Power Generation ...... ５ 2. Diversion shute ...... ７ 2.1 DischargeTime Sequence ...... ７ 2.2 Duration Curve ...... ９ 2.3 Power Generation ...... １１ 3. Bayongan ...... １３ 3.1 Reservior Operation ...... １３ 3.2 Duration Curve ...... １５ 3.3 Power Generation ...... １６ 4. Estimated construction costs ...... 18 4.1 Operation＿A ...... 18 4.2 Operation＿B ...... 19 4.3 Operation＿C ...... 20 4.4 Operation＿D ...... 21

Attachment 7 1. Malinao 1.1 Reservior Operation

Malinao Reservior operation-A (2005-2017) 155.00 35.00

150.00 30.00

145.00 25.00

140.00 20.00

135.00 15.00 Water Level (EL.m)) Level Water Inflow Water Level Discharge Q(m3/s) 130.00 10.00 Inflow Outflow Outflow

125.00 5.00 Spillway Outflow

Generation Spillway Outflow 120.00 0.00 2005/1/1 2006/1/1 2007/1/1 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1

Year/Month/Day Fig.-1.1(1) Malinao Reservior Operation（Operation＿A）

Malinao Reservior operation-B (2005-2017) 155.00 35.00

150.00 30.00

145.00 25.00

140.00 20.00

135.00 15.00 Water Level (EL.m)) Level Water Water Levvel

Outflow Discharge Q(m3/s) 130.00 10.00 Inflow

Generation Outflow 125.00 5.00 Spillway Outflow Spillway Outflow Generation

120.00 0.00 2005/1/1 2006/1/1 2007/1/1 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1

Year/Month/Day Fig.-1.1(2) Malinao Reservior Operation（Operation＿B）

Attachment 7 Malinao Reservior operation-C (2005-2017) 155.00 35.00

150.00 30.00

145.00 25.00

140.00 20.00

135.00 15.00 Water Level (EL.m)) Level Water Water Levvel

Outflow Discharge Q(m3/s) 130.00 10.00 Inflow

Outflow

125.00 5.00 Spillway outflow Spillway outflow Generation

120.00 0.00 2005/1/1 2006/1/1 2007/1/1 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1

Year/Month/Day Fig.-1.1(3) Malinao Reservior Operation（Operation＿C）

Malinao Reservior operation-D (2005-2017) 155.00 35.00

150.00 30.00

145.00 25.00

140.00 20.00

135.00 15.00 Water Level (EL.m)) Level Water Water Levvel

Outflow Discharge Q(m3/s) 130.00 10.00 Inflow

Outflow

125.00 5.00 Spillway outflow Spillway outflow Generation

120.00 0.00 2005/1/1 2006/1/1 2007/1/1 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1

Year/Month/Day Fig.-1.1(4) Malinao Reservior Operation（Operation＿D）

Attachment 7 1.2 Duration Curve

Malinao Intake Outflow Operation_A Malinao Intake Outflow Operation_B 12.00 12.00 2,005 2,006 2,007 2,008 2,005 2,006 2,007 2,008 2,009 2,010 2,011 2,012 2,009 2,010 2,011 2,012 2,013 2,014 2,015 2,016 2,013 2,014 2,015 2,016 2,017 2,018 average 2,017 2,018 average 10.00 10.00

8.00 8.00 Q(m3/s)) Q(m3/s))

6.00 6.00 Discharge Discharge

4.00 4.00

2.00 2.00

- - - 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 - 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360

Fig.-1.2(1) Malinao Duration Curve（Operation＿A） Fig.-1.2(2) Malinao Duration Curve（Operation＿B）

Attachment 7 Malinao Intake Outflow Operation_C Malinao Intake Outflow Operation_D 12.00 12.00 2,005 2,006 2,007 2,008 2,005 2,006 2,007 2,008 2,009 2,010 2,011 2,012 2,009 2,010 2,011 2,012 2,013 2,014 2,015 2,016 2,013 2,014 2,015 2,016 2,017 2,018 average 2,017 2,018 average 10.00 10.00

8.00 8.00 Q(m3/s)) Q(m3/s))

6.00 6.00 Discharge Discharge

4.00 4.00

2.00 2.00

- - - 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 - 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360

Fig.-1.2(3) Malinao Duration Curve（Operation＿C） Fig.-1.2(4) Malinao Duration Curve（Operation＿D）

Attachment 7 1.3 Power Generation

Malino generation(6.0MCM) Operation_A 300

250

200

150 Generation P(kW)

100

50

0 2005/1/1 2005/3/1 2005/5/1 2005/7/1 2005/9/1 2006/1/1 2006/3/1 2006/5/1 2006/7/1 2006/9/1 2007/1/1 2007/3/1 2007/5/1 2007/7/1 2007/9/1 2008/1/1 2008/3/1 2008/5/1 2008/7/1 2008/9/1 2009/1/1 2009/3/1 2009/5/1 2009/7/1 2009/9/1 2010/1/1 2010/3/1 2010/5/1 2010/7/1 2010/9/1 2011/1/1 2011/3/1 2011/5/1 2011/7/1 2011/9/1 2012/1/1 2012/3/1 2012/5/1 2012/7/1 2012/9/1 2013/1/1 2013/3/1 2013/5/1 2013/7/1 2013/9/1 2014/1/1 2014/3/1 2014/5/1 2014/7/1 2014/9/1 2015/1/1 2015/3/1 2015/5/1 2015/7/1 2015/9/1 2016/1/1 2016/3/1 2016/5/1 2016/7/1 2016/9/1 2017/1/1 2017/3/1 2017/5/1 2017/7/1 2017/9/1 2018/1/1 2018/3/1 2018/5/1 2018/7/1 2005/11/1 2006/11/1 2009/11/1 2010/11/1 2011/11/1 2014/11/1 2015/11/1 2007/11/1 2008/11/1 2012/11/1 2013/11/1 2016/11/1 2017/11/1 year/month/day

Fig.-1.3(1) MalinaoPower Generation（Operation＿A）

Malino generation operation_B 300

250

200

150 Generation P(kW)

100

50

0 2005/1/1 2005/3/1 2005/5/1 2005/7/1 2005/9/1 2006/1/1 2006/3/1 2006/5/1 2008/1/1 2008/3/1 2008/5/1 2008/7/1 2010/9/1 2011/1/1 2011/3/1 2011/5/1 2011/7/1 2011/9/1 2012/1/1 2012/3/1 2012/5/1 2012/7/1 2012/9/1 2013/1/1 2013/7/1 2013/9/1 2014/1/1 2014/3/1 2014/5/1 2014/7/1 2014/9/1 2015/1/1 2015/3/1 2016/5/1 2016/7/1 2016/9/1 2017/1/1 2017/3/1 2017/5/1 2006/7/1 2006/9/1 2007/1/1 2007/3/1 2007/5/1 2007/7/1 2007/9/1 2008/9/1 2009/1/1 2009/3/1 2009/5/1 2009/7/1 2009/9/1 2010/1/1 2010/3/1 2010/5/1 2010/7/1 2013/3/1 2013/5/1 2015/5/1 2015/7/1 2015/9/1 2016/1/1 2016/3/1 2017/7/1 2017/9/1 2018/1/1 2018/3/1 2018/5/1 2018/7/1 2005/11/1 2006/11/1 2007/11/1 2008/11/1 2009/11/1 2010/11/1 2011/11/1 2012/11/1 2013/11/1 2014/11/1 2015/11/1 2016/11/1 2017/11/1 year/month/day

Fig.-1.3(2) MalinaoPower Generation（Operation＿B）

Attachment 7 Malino generation(8.0MCM) operation_C 300

250

200

150 Generation P(kW) 100

50

0 2005/1/1 2005/3/1 2005/5/1 2005/7/1 2005/9/1 2006/1/1 2006/3/1 2006/5/1 2006/7/1 2006/9/1 2007/1/1 2007/3/1 2007/5/1 2007/7/1 2007/9/1 2008/1/1 2008/3/1 2008/5/1 2008/7/1 2008/9/1 2009/1/1 2009/3/1 2009/5/1 2009/7/1 2009/9/1 2010/1/1 2010/3/1 2010/5/1 2010/7/1 2010/9/1 2011/1/1 2011/3/1 2011/5/1 2011/7/1 2011/9/1 2012/1/1 2012/3/1 2012/5/1 2012/7/1 2012/9/1 2013/1/1 2013/3/1 2013/5/1 2013/7/1 2013/9/1 2014/1/1 2014/3/1 2014/5/1 2014/7/1 2014/9/1 2015/1/1 2015/3/1 2015/5/1 2015/7/1 2015/9/1 2016/1/1 2016/3/1 2016/5/1 2016/7/1 2016/9/1 2017/1/1 2017/3/1 2017/5/1 2017/7/1 2017/9/1 2018/1/1 2018/3/1 2018/5/1 2018/7/1 2005/11/1 2006/11/1 2009/11/1 2010/11/1 2011/11/1 2012/11/1 2013/11/1 2014/11/1 2015/11/1 2016/11/1 2017/11/1 2007/11/1 2008/11/1 year/month/day

Fig.-1.3(3) MalinaoPower Generation（Operation＿C）

Malino generation(8.0MCM) operation_D 300

250

200

150 Generation P(kW) 100

50

0 2005/1/1 2005/3/1 2005/5/1 2005/7/1 2005/9/1 2006/1/1 2006/3/1 2006/5/1 2006/7/1 2006/9/1 2007/1/1 2007/3/1 2007/5/1 2007/7/1 2007/9/1 2008/1/1 2008/3/1 2008/5/1 2008/7/1 2008/9/1 2009/1/1 2009/3/1 2009/5/1 2009/7/1 2009/9/1 2010/1/1 2010/3/1 2010/5/1 2010/7/1 2010/9/1 2011/1/1 2011/3/1 2011/5/1 2011/7/1 2011/9/1 2012/1/1 2012/3/1 2012/5/1 2012/7/1 2012/9/1 2013/1/1 2013/7/1 2013/9/1 2014/1/1 2014/3/1 2014/5/1 2014/7/1 2014/9/1 2015/1/1 2015/3/1 2015/5/1 2015/7/1 2015/9/1 2016/1/1 2016/3/1 2016/5/1 2016/7/1 2016/9/1 2017/1/1 2017/3/1 2017/5/1 2017/7/1 2017/9/1 2018/1/1 2018/3/1 2018/5/1 2018/7/1 2013/3/1 2013/5/1 2005/11/1 2006/11/1 2007/11/1 2008/11/1 2009/11/1 2010/11/1 2011/11/1 2012/11/1 2013/11/1 2014/11/1 2015/11/1 2016/11/1 2017/11/1 year/month/day

Fig.-1.3(4) MalinaoPower Generation（Operation＿D）

Attachment 7 2. Diversion shute 2.1 DischargeTime Sequence

Diversion shute Discrage(Operatin_A) 7.00

6.00

5.00

4.00

Operation_A 3.00 Discharge (m3/s))

2.00

1.00

- 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 Year/Month/Day

Fig.-2.1(1) Diversion shute DischargeTime Sequence Operation_A

Diversion shute Discrage(Operaton_B) 8.00

7.00

6.00

5.00

4.00 Operation_B

Discharge (m3/s)) 3.00

2.00

1.00

0.00 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 Year/Month/Day

Fig.-2.1(2) Diversion shute DischargeTime Sequence Operation_B

Attachment 7 Diversion shute Discrage(Operation_C) 8.00

7.00

6.00

5.00

4.00 Operation_C

Discharge (m3/s)) 3.00

2.00

1.00

0.00 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 Year/Month/Day

Fig.-2.1（3） Diversion shute DischargeTime Sequence Operation_C

Diversion shute Discrage(Operation_D) 9.00

8.00

7.00

6.00

5.00

4.00 Operation_D Discharge (m3/s))

3.00

2.00

1.00

0.00 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 Year/Month/Day

Fig.-2.1(4) Diversion shute DischargeTime Sequence Operation_D

Attachment 7 2.2 Duration Curve

Diversion shute operation_A Diversion shute operation_B 10.00 10.00 2,008 2,009 2,008 2,009 2,010 2,011 2,010 2,011 9.00 2,012 2,013 9.00 2,012 2,013 2,014 2,015 2,014 2,015 2,016 2,017 average 2,016 2,017 8.00 average(except for 2008,2009) 8.00

7.00 7.00 Q(m3/s)) Q(m3/s)) 6.00 6.00

5.00 5.00 Discharge Discharge

4.00 4.00

3.00 3.00

2.00 2.00

1.00 1.00

- - - 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 - 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360

Fig.-2.2(1) Diversion shuteDuration Curve（Operation＿ Fig.-2.2(2) Diversion shuteDuration Curve（Operation＿B） A）

Attachment 7 Diversion shute operation_C Diversion shute operation_D 10.00 10.00 2,008 2,009 2,010 2,011 2,008 2,009 2,010 2,011

9.00 2,012 2,013 2,014 2,015 9.00 2,012 2,013 2,014 2,015

2,016 2,017 average 2,016 2,017 average 8.00 8.00

7.00 7.00 Q(m3/s)) 6.00 Q(m3/s)) 6.00

5.00 5.00 Discharge Discharge

4.00 4.00

3.00 3.00

2.00 2.00

1.00 1.00

- - - 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360 - 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360

Fig.-2.2(3) Diversion shuteDuration Curve（Operation＿C） Fig.-2.2(4) Diversion shuteDuration Curve（Operation＿D）

Attachment 7 2.3 Power Generation

Diversion shute Generation Operation-A 1,200

1,000

800

600 Generation P(kW)

400

200

0 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 year/month/day

Fig.-2.3(1) Diversion shutePower Generation（Operation＿A）

Diversion shute Generation Operation _B 1,200

1,000

800

600 Generation P(kW)

400

200

0 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 year/month/day

Fig.-2.3(2) Diversion shutePower Generation（Operation＿B）

Attachment 7 Diversion shute generation(operation_C) 1,200

1,000

800

600 Generation P(kW)

400

200

0 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 year/month/day

Fig.-2.3(3) Diversion shutePower Generation（Operation＿C）

Diversion shute Generation Operation_D 1,200

1,000

800

600 Generation P(kW)

400

200

0 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 year/month/day

Fig.-2.3(4) Diversion shutePower Generation（Operation＿D）

Attachment 7 3. Bayongan 3.1 Reservior Operation

Bayongan Reservior Operation-A 60.00 30.00 Water Level

50.00 25.00

40.00 20.00 (EL.m) Level (m3/s) 30.00 15.00 Water Level Water Inflow

Infl ow Discharege Outflow 20.00 10.00

Reservior Outflow Generation

Generation

10.00 5.00

0.00 0.00 2008/1/1 2008/3/1 2008/5/1 2008/7/1 2008/9/1 2009/1/1 2009/3/1 2009/5/1 2009/7/1 2009/9/1 2010/1/1 2010/3/1 2010/5/1 2010/7/1 2010/9/1 2011/1/1 2011/3/1 2011/5/1 2011/7/1 2011/9/1 2012/1/1 2012/3/1 2012/5/1 2012/7/1 2012/9/1 2013/1/1 2013/3/1 2013/5/1 2013/7/1 2013/9/1 2014/1/1 2014/3/1 2014/5/1 2014/7/1 2014/9/1 2015/1/1 2015/3/1 2015/5/1 2015/7/1 2015/9/1 2016/1/1 2016/3/1 2016/5/1 2016/7/1 2016/9/1 2017/1/1 2017/3/1 2017/5/1 2017/7/1 2017/9/1 2018/1/1 2008/11/1 2009/11/1 2010/11/1 2011/11/1 2012/11/1 2013/11/1 2014/11/1 2015/11/1 2016/11/1 2017/11/1 Year/Month/Day

Fig.-3.1(1) Bayongan Reservior Operation（Operation＿A）

Bayongan Reservior Operation-B 60.00 30.00

50.00 25.00

40.00 20.00 (EL.m) Level (m3/s) 30.00 15.00 Water Level Water Inflow

Discharege Outflow 20.00 10.00

Reservior Outflow Generation

10.00 5.00

0.00 0.00 2008/1/1 2008/3/1 2008/5/1 2008/7/1 2008/9/1 2009/1/1 2009/3/1 2009/5/1 2009/7/1 2009/9/1 2010/1/1 2010/3/1 2010/5/1 2010/7/1 2010/9/1 2011/1/1 2011/3/1 2011/5/1 2011/7/1 2011/9/1 2012/1/1 2012/3/1 2012/5/1 2012/7/1 2012/9/1 2013/1/1 2013/3/1 2013/5/1 2013/7/1 2013/9/1 2014/1/1 2014/3/1 2014/5/1 2014/7/1 2014/9/1 2015/1/1 2015/3/1 2015/5/1 2015/7/1 2015/9/1 2016/1/1 2016/3/1 2016/5/1 2016/7/1 2016/9/1 2017/1/1 2017/3/1 2017/5/1 2017/7/1 2017/9/1 2018/1/1 2008/11/1 2009/11/1 2010/11/1 2011/11/1 2012/11/1 2013/11/1 2014/11/1 2015/11/1 2016/11/1 2017/11/1 Year/Month/Day

Fig.-3.1(2) Bayongan Reservior Operation（Operation＿B）

Attachment 7 Bayongan Reservior Operation-C 60.00 30.00

50.00 25.00

40.00 20.00 (EL.m) Level (m3/s) 30.00 15.00 Water Level Water Inflow

Discharege Outflow 20.00 10.00

Reservior Outflow Generation

10.00 5.00

0.00 0.00 2008/1/1 2008/3/1 2008/5/1 2008/7/1 2008/9/1 2009/1/1 2009/3/1 2009/5/1 2009/7/1 2009/9/1 2010/1/1 2010/3/1 2012/1/1 2012/3/1 2012/5/1 2012/7/1 2012/9/1 2013/1/1 2013/3/1 2013/5/1 2013/7/1 2016/5/1 2016/7/1 2016/9/1 2017/1/1 2017/3/1 2017/5/1 2017/7/1 2017/9/1 2018/1/1 2010/5/1 2010/7/1 2010/9/1 2011/1/1 2011/3/1 2011/5/1 2011/7/1 2011/9/1 2013/9/1 2014/1/1 2014/3/1 2014/5/1 2014/7/1 2014/9/1 2015/1/1 2015/3/1 2015/5/1 2015/7/1 2015/9/1 2016/1/1 2016/3/1 2008/11/1 2009/11/1 2010/11/1 2011/11/1 2012/11/1 2013/11/1 2014/11/1 2015/11/1 2016/11/1 2017/11/1 Year/Month/Day

Fig.-3.1(3) Bayongan Reservior Operation（Operation＿C）

Bayongan Reservior Operation-D 60.00 30.00

50.00 25.00

40.00 20.00 (EL.m) Level (m3/s) 30.00 15.00 Water Level Water Inflow

Discharege Outflow 20.00 10.00

Reservior Outflow Generation

10.00 5.00

0.00 0.00 2008/1/1 2008/3/1 2008/5/1 2008/7/1 2008/9/1 2009/1/1 2009/3/1 2009/5/1 2009/7/1 2009/9/1 2010/1/1 2010/3/1 2010/5/1 2010/7/1 2010/9/1 2011/1/1 2011/3/1 2011/5/1 2011/7/1 2011/9/1 2012/1/1 2012/3/1 2012/5/1 2012/7/1 2012/9/1 2013/1/1 2013/3/1 2013/5/1 2013/7/1 2013/9/1 2014/1/1 2014/3/1 2014/5/1 2014/7/1 2014/9/1 2015/1/1 2015/3/1 2015/5/1 2015/7/1 2015/9/1 2016/1/1 2016/3/1 2016/5/1 2016/7/1 2016/9/1 2017/1/1 2017/3/1 2017/5/1 2017/7/1 2017/9/1 2018/1/1 2008/11/1 2009/11/1 2010/11/1 2011/11/1 2012/11/1 2013/11/1 2014/11/1 2015/11/1 2016/11/1 2017/11/1 Year/Month/Day

Fig.-3.1(4) Bayongan Reservior Operation（Operation＿D）

Attachment 7 3.2 Duration Curve

Bayongan intake outflow 10.00 2,008 2,009 2,010 2,011 9.00 2,012 2,013 2,014 2,015 2,016 2,017 8.00 average(except for 2008,2009)

7.00

Q(m3/s)) 6.00

5.00 Discharge

4.00

3.00

2.00

1.00

- - 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300 320 340 360

Fig.-3.2 Bayongan Duration Curve（Operation＿D） ※ Malinao reservior operation has no effecto to Bayongan intake outlet discharge

Attachment 7 3.3 Power Generation

Bayongan generation(operation_A (present)) 350

300

250

200

150 Generation P(kW)

100

50

0 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 year/month/day

Fig.-3.3(1) Bayongan Power Generation(Operation＿A）

Bayongan generation(operation_B) 250

200

150

Generation P(kW) 100

50

0 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 year/month/day

Fig.-3.3(2) Bayongan Power Generation（Operation＿B）

Attachment 7 Bayongan generation(operation_C) 250

200

150

100 Generation P(kW)

50

0 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 year/month/day

Fig.-3.3(3) Bayongan Power Generation（Operation＿C）

Bayongan generation(operation_D) 250

200

150

Generation P(kW) 100

50

0 2008/1/1 2009/1/1 2010/1/1 2011/1/1 2012/1/1 2013/1/1 2014/1/1 2015/1/1 2016/1/1 2017/1/1 year/month/day

Fig.-3.3(4) Bayongan Power Generation（Operation＿D）

Attachment 7 4. Estimated construction costs 4.1 Operation＿A

Diversion Diversion Diversion Diversion Diversion Diversion Diversion Bayongan Bayongan Bayongan Bayongan Bayongan Bayongan Malinao＿1 Malinao＿2 Malinao＿3 Malinao＿4 Malinao＿5 Malinao＿6 shute_1 shute_2 shute_3 shute_4 shute_5 shute_6 shute_7 ＿1 ＿2 ＿3 ＿4 ＿5 ＿6 1. Design condition Pmax Pmax kw 428 374 321 267 214 160 2,336 2,077 1,817 1,557 1,298 1,038 779 370 324 277 231 185 139 Max. Discharge Qmax m3/s 8.00 7.00 6.00 5.00 4.00 3.00 4.50 4.00 3.50 3.00 2.50 2.00 1.50 4.00 3.50 3.00 2.50 2.00 1.50 Average Discharage Qave m3/s 3.41 3.27 3.04 2.73 2.33 1.82 0.69 0.68 0.65 0.61 0.56 0.49 0.41 1.31 1.24 1.14 1.00 0.85 0.67 Annual Generation ΣP Mwh 1,097 1,072 1,012 916 789 620 2,607 2,641 2,644 2,597 2,482 2,274 1,946 600 585 553 502 435 351 Effective Head He ｍ 7.2 7.2 7.2 7.2 7.2 7.2 67.2 67.2 67.2 67.2 67.2 67.2 67.2 12.5 12.5 12.5 12.5 12.5 12.5 Penstock diameter D ｍ 2.0 2.0 2.0 2.0 2.0 2.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.5 1.5 1.5 1.5 1.5 1.5 water way Radius r ｍ 1.0 1.0 1.0 1.0 1.0 1.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.8 0.8 0.8 0.8 0.8 0.8 Penstock length Lp ｍ 25.0 25.0 25.0 25.0 25.0 25.0 280.0 280.0 280.0 280.0 280.0 280.0 280.0 25.0 25.0 25.0 25.0 25.0 25.0 Outlet channel length Lo ｍ 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 Turbine type Tubular Tubular Tubular Tubular Tubular Tubular Francis Francis Francis Francis Francis Francis Francis Tubular Tubular Tubular Tubular Tubular Tubular Number of turbine n 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 above above above above above above above above above above above above above above above above above above above Power house type ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground 2. Construction cost(total) 106 JPY 583 535 486 435 381 323 1,349 1,277 1,203 1,126 1,046 960 868 441 406 370 332 293 250 1PHP= 2.15 JPN 106 PHP 271 249 226 202 177 150 627 594 560 524 486 447 404 205 189 172 155 136 116 2.1 Architecture(Power house ) 106 JPY 13 11 10 9 7 6 52 48 43 37 32 27 21 11 10 9 8 6 5 Y=a*Xｂ a 0.084 ｂ 0.83 2.2 Civil work 104 100 96 91 86 81 534 518 501 485 468 451 433 84 81 78 75 72 69 2.2.1 Water way 92 89 87 84 81 77 482 472 462 451 439 427 413 75 74 72 70 68 65 (1) Intake 106 JPY 0 0 0 0 0 0 30 28 26 24 22 20 17 0 0 0 0 0 0 (Non.pressure type） X=r*Q 2.25 2 1.75 1.5 1.25 1 0.75 Y=a*Xｂ a 19.7 b 0.506 106 JPY (2) Head tank 82 76 69 62 55 48 39 X=Q Y=a*Xｂ a 29.9 b 0.669 (3) Penstock pipe 106 JPY 38 38 38 38 38 38 275 275 275 275 275 275 275 37 37 37 37 37 37 Unit weight W=ａ＊Ｘ+ｂ ｔ/ｍ 0.22 0.22 0.22 0.22 0.22 0.22 0.38 0.38 0.38 0.38 0.38 0.38 0.38 0.24 0.24 0.24 0.24 0.24 0.24 a 0.0026 b 0.20640 Weight ｔ 5.6 5.6 5.6 5.6 5.6 5.6 106.1 106.1 106.1 106.1 106.1 106.1 106.1 6.0 6.0 6.0 6.0 6.0 6.0 Unite price 103 JPY/t 1,513 1,513 1,513 1,513 1,513 1,513 982 982 982 982 982 982 982 1,500 1,500 1,500 1,500 1,500 1,500 Y=a*Xｂ a 1950 b -0.147 (4) Penstock(w.o penstock pipe) 106 JPY 9 9 9 9 9 9 45 45 45 45 45 45 45 6 6 6 6 6 6 Unite price 103 JPY/m 357 357 357 357 357 357 162 162 162 162 162 162 162 257 257 257 257 257 257 Y=a*Xｂ a 357 b 1.14 (5) Outlet(Non pressure type) 106 JPY 23 22 21 19 17 15 14 13 12 11 11 10 8 15 14 14 13 11 10 X=r*Q 8 7 6 5 4 3 2.25 2 1.75 1.5 1.25 1 0.75 3 2.625 2.25 1.875 1.5 1.125 Y=a*Xｂ a 9.54 b 0.432 (6) Outlet channel 106 JPY 17 16 15 14 13 11 13 13 12 11 10 9 8 13 12 11 10 9 8 Y=√(B・H）＝a*Xb 2.40 2.28 2.15 2.01 1.84 1.65 1.93 1.84 1.75 1.65 1.54 1.42 1.27 1.84 1.75 1.65 1.54 1.42 1.27 a 1.09 ｂ 0.379 Y=a*Xｂ a 122 103 JPY/m 345 325 303 279 253 222 266 253 238 222 204 185 162 253 238 222 204 185 162 ｂ 1.19 sub total((1)～(6)) 87 85 83 80 77 73 459 449 440 429 418 406 393 72 70 69 67 65 62 （7) other work(=sub-total*0.05) 4 4 4 4 4 4 23 22 22 21 21 20 20 4 4 3 3 3 3 2.2.2 Mechanical equipment 106 JPY 9 8 6 5 3 2 37 31 25 20 15 11 7 6 5 4 3 2 1 (1) Mechanical equipment(above ground type)foundation X=Q*He2/3*n1/2 30 26 22 19 15 11 74 66 58 50 41 33 25 21 19 16 13 11 8 Y=a*Xｂ a 0.0595 b 1.49 Sub total(2.2～2.3) 106 JPY 101 97 93 88 84 79 518 503 487 471 455 438 420 81 79 76 73 70 67 2.2.3 Related appratus(3%) 106 JPY 3 3 3 3 3 2 16 15 15 14 14 13 13 2 2 2 2 2 2 2.3 Electrical equipment 106 JPY 352 319 286 250 213 173 499 462 424 384 341 295 245 260 236 211 185 157 127 X=Pmax/He1/2 159 140 120 100 80 60 285 253 222 190 158 127 95 105 92 79 66 52 39 Tubular a 8.9000 b 0.7250 Francis a 12.8000 b 0.6480 2.4 Cost for temporary facilities 47 43 39 35 31 26 109 103 97 91 84 77 70 35 33 30 27 24 20 （2.1+2.2+2.3）×0.1 2.5 General expense 67 62 56 50 44 37 155 147 138 130 120 110 100 51 47 43 38 34 29 (2.1+2.2+2.3+2.4)×0.13 2 Annual generation ΣP Mwh 1,097 1,072 1,012 916 789 620 2,607 2,641 2,644 2,597 2,482 2,274 1,946 600 585 553 502 435 351 Unit construction cost JPY/kwh 531 499 481 475 483 521 517 484 455 434 421 422 446 735 694 669 662 673 712 PHP/kwh 247 232 223 221 225 242 241 225 212 202 196 196 208 342 323 311 308 313 331

Attachment 7 4.2 Operation＿B

Diversion Diversion Diversion Diversion Diversion Diversion Diversion Bayongan Bayongan Bayongan Bayongan Bayongan Bayongan Malinao＿1 Malinao＿2 Malinao＿3 Malinao＿4 Malinao＿5 Malinao＿6 shute_1 shute_2 shute_3 shute_4 shute_5 shute_6 shute_7 ＿1 ＿2 ＿3 ＿4 ＿5 ＿6 1. Design condition Pmax Pmax kw 394 345 296 246 197 148 2,336 2,077 1,817 1,557 1,298 1,038 779 366 320 274 229 183 137 Max. discharge Qmax m3/s 8.00 7.00 6.00 5.00 4.00 3.00 4.50 4.00 3.50 3.00 2.50 2.00 1.50 4.00 3.50 3.00 2.50 2.00 1.50 Average discharage Qave m3/s 3.66 3.52 3.30 2.99 2.60 2.11 1.02 1.00 0.96 0.92 0.86 0.78 0.68 1.31 1.24 1.14 1.00 0.85 0.67 Annual Generation ΣP Mwh 992 972 919 837 728 584 3,717 3,760 3,768 3,738 3,644 3,451 3,144 609 595 563 511 443 358 Effective head He ｍ 6.5 6.5 6.5 6.5 6.5 6.5 67.2 67.2 67.2 67.2 67.2 67.2 67.2 12.3 12.3 12.3 12.3 12.3 12.3 Penstock diameter D ｍ 2.0 2.0 2.0 2.0 2.0 2.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.5 1.5 1.5 1.5 1.5 1.5 water way Radius r ｍ 1.0 1.0 1.0 1.0 1.0 1.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.8 0.8 0.8 0.8 0.8 0.8 Penstock length Lp ｍ 25.0 25.0 25.0 25.0 25.0 25.0 280.0 280.0 280.0 280.0 280.0 280.0 280.0 25.0 25.0 25.0 25.0 25.0 25.0 Outlet channel length Lo ｍ 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 Turbine type Tubular Tubular Tubular Tubular Tubular Tubular Francis Francis Francis Francis Francis Francis Francis Tubular Tubular Tubular Tubular Tubular Tubular Number of turbine n 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 above above above above above above above above above above above above above above above above above above above Power house type ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground 2. Construction cost(total) 106 JPY 571 525 477 427 374 318 1,349 1,277 1,203 1,126 1,046 960 868 439 405 369 331 292 249 1PHP= 2.15 JPN 106 PHP 266 244 222 199 174 148 627 594 560 524 486 447 404 204 188 172 154 136 116 2.1 Architecture(Power house ) 106 JPY 12 11 9 8 7 5 52 48 43 37 32 27 21 11 10 9 8 6 5 Y=a*Xｂ a 0.084 ｂ 0.83 2.2 Civil work 103 99 95 91 86 81 534 518 501 485 468 451 433 84 81 78 75 72 69 2.2.1 Water way 92 89 87 84 81 77 482 472 462 451 439 427 413 75 74 72 70 68 65 (1) Intake 106 JPY 0 0 0 0 0 0 30 28 26 24 22 20 17 0 0 0 0 0 0 (Non.pressure type） X=r*Q 2.25 2 1.75 1.5 1.25 1 0.75 Y=a*Xｂ a 19.7 b 0.506 106 JPY (2) Head tank 82 76 69 62 55 48 39 X=Q Y=a*Xｂ a 29.9 b 0.669 (3) Penstock pipe 106 JPY 38 38 38 38 38 38 275 275 275 275 275 275 275 38 38 38 38 38 38 Unit weight W=ａ＊Ｘ+ｂ ｔ/ｍ 0.22 0.22 0.22 0.22 0.22 0.22 0.38 0.38 0.38 0.38 0.38 0.38 0.38 0.24 0.24 0.24 0.24 0.24 0.24 a 0.0026 b 0.20640 Weight ｔ 5.6 5.6 5.6 5.6 5.6 5.6 106.1 106.1 106.1 106.1 106.1 106.1 106.1 5.9 5.9 5.9 5.9 5.9 5.9 Unite price 103 JPY/t 1,515 1,515 1,515 1,515 1,515 1,515 982 982 982 982 982 982 982 1,500 1,500 1,500 1,500 1,500 1,500 Y=a*Xｂ a 1950 b -0.147 (4) Penstock(w.o penstock pipe) 106 JPY 9 9 9 9 9 9 45 45 45 45 45 45 45 6 6 6 6 6 6 Unite price 103 JPY/m 357 357 357 357 357 357 162 162 162 162 162 162 162 257 257 257 257 257 257 Y=a*Xｂ a 357 b 1.14 (5) Outlet(Non pressure type) 106 JPY 23 22 21 19 17 15 14 13 12 11 11 10 8 15 14 14 13 11 10 X=r*Q 8 7 6 5 4 3 2.25 2 1.75 1.5 1.25 1 0.75 3 2.625 2.25 1.875 1.5 1.125 Y=a*Xｂ a 9.54 b 0.432 (6) Outlet channel 106 JPY 17 16 15 14 13 11 13 13 12 11 10 9 8 13 12 11 10 9 8 Y=√(B・H）＝a*Xb 2.40 2.28 2.15 2.01 1.84 1.65 1.93 1.84 1.75 1.65 1.54 1.42 1.27 1.84 1.75 1.65 1.54 1.42 1.27 a 1.09 ｂ 0.379 Y=a*Xｂ a 122 103 JPY/m 345 325 303 279 253 222 266 253 238 222 204 185 162 253 238 222 204 185 162 ｂ 1.19 sub total((1)～(6)) 87 85 83 80 77 73 459 449 440 429 418 406 393 72 70 69 67 65 62 （7) other work(=sub-total*0.05) 4 4 4 4 4 4 23 22 22 21 21 20 20 4 4 3 3 3 3 2.2.2 Mechanical equipment 106 JPY 8 7 6 4 3 2 37 31 25 20 15 11 7 6 5 4 3 2 1 (1) Mechanical equipment(above ground type)foundation X=Q*He2/3*n1/2 28 24 21 17 14 10 74 66 58 50 41 33 25 21 19 16 13 11 8 Y=a*Xｂ a 0.0595 b 1.49 Sub total(2.2～2.3) 106 JPY 100 96 92 88 84 79 518 503 487 471 455 438 420 81 78 76 73 70 67 2.2.3 Related appratus(3%) 106 JPY 3 3 3 3 3 2 16 15 15 14 14 13 13 2 2 2 2 2 2 2.3 Electrical equipment 106 JPY 344 312 279 245 208 169 499 462 424 384 341 295 245 259 235 210 184 156 127 X=Pmax/He1/2 155 135 116 97 77 58 285 253 222 190 158 127 95 104 91 78 65 52 39 Tubular a 8.9000 b 0.7250 Francis a 12.8000 b 0.6480 2.4 Cost for temporary facilities 46 42 38 34 30 26 109 103 97 91 84 77 70 35 33 30 27 23 20 （2.1+2.2+2.3）×0.1 2.5 General expense 66 60 55 49 43 37 155 147 138 130 120 110 100 51 47 42 38 34 29 (2.1+2.2+2.3+2.4)×0.13 2 Annual generation ΣP Mwh 992 972 919 837 728 584 3,717 3,760 3,768 3,738 3,644 3,451 3,144 609 595 563 511 443 358 Unit construction cost JPY/kwh 575 540 519 510 514 543 363 340 319 301 287 278 276 721 680 655 649 658 696 PHP/kwh 268 251 241 237 239 253 169 158 148 140 133 129 128 336 316 305 302 306 324

Attachment 7 4.3 Operation＿C

Diversion Diversion Diversion Diversion Diversion Diversion Diversion Bayongan Bayongan Bayongan Bayongan Bayongan Bayongan Malinao＿1 Malinao＿2 Malinao＿3 Malinao＿4 Malinao＿5 Malinao＿6 shute_1 shute_2 shute_3 shute_4 shute_5 shute_6 shute_7 ＿1 ＿2 ＿3 ＿4 ＿5 ＿6 1. Design condition Pmax Pmax kw 463 405 347 290 232 174 2,336 2,077 1,817 1,557 1,298 1,038 779 366 320 274 229 183 137 Max. discharge Qmax m3/s 8.00 7.00 6.00 5.00 4.00 3.00 4.50 4.00 3.50 3.00 2.50 2.00 1.50 4.00 3.50 3.00 2.50 2.00 1.50 Average discharage Qave m3/s 3.71 3.57 3.34 3.03 2.64 2.14 1.04 1.01 0.97 0.93 0.87 0.79 0.69 1.31 1.24 1.14 1.00 0.85 0.67 Annual Generation ΣP Mwh 1,219 1,195 1,131 1,032 900 724 3,749 3,793 3,801 3,770 3,675 3,479 3,171 609 595 563 511 443 358 Effective head He ｍ 7.8 7.8 7.8 7.8 7.8 7.8 67.2 67.2 67.2 67.2 67.2 67.2 67.2 12.3 12.3 12.3 12.3 12.3 12.3 Penstock diameter D ｍ 2.0 2.0 2.0 2.0 2.0 2.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.5 1.5 1.5 1.5 1.5 1.5 water way Radius r ｍ 1.0 1.0 1.0 1.0 1.0 1.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.8 0.8 0.8 0.8 0.8 0.8 Penstock length Lp ｍ 25.0 25.0 25.0 25.0 25.0 25.0 280.0 280.0 280.0 280.0 280.0 280.0 280.0 25.0 25.0 25.0 25.0 25.0 25.0 Outlet channel length Lo ｍ 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 Turbine type Tubular Tubular Tubular Tubular Tubular Tubular Francis Francis Francis Francis Francis Francis Francis Tubular Tubular Tubular Tubular Tubular Tubular Number of turbine n 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 above above above above above above above above above above above above above above above above above above above Power house type ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground 2. Construction cost(total) 106 JPY 598 549 498 445 390 330 1,349 1,277 1,203 1,126 1,046 960 868 439 405 369 331 292 249 1PHP= 2.15 JPN 106 PHP 278 255 232 207 181 153 627 594 560 524 486 447 404 204 188 172 154 136 116 2.1 Architecture(Power house ) 106 JPY 14 12 11 9 8 6 52 48 43 37 32 27 21 11 10 9 8 6 5 Y=a*Xｂ a 0.084 ｂ 0.83 2.2 Civil work 105 101 96 91 87 82 534 518 501 485 468 451 433 84 81 78 75 72 69 2.2.1 Water way 92 89 87 84 81 77 482 472 462 451 439 427 413 75 74 72 70 68 65 (1) Intake 106 JPY 0 0 0 0 0 0 30 28 26 24 22 20 17 0 0 0 0 0 0 (Non.pressure type） X=r*Q 2.25 2 1.75 1.5 1.25 1 0.75 Y=a*Xｂ a 19.7 b 0.506 106 JPY (2) Head tank 82 76 69 62 55 48 39 X=Q Y=a*Xｂ a 29.9 b 0.669 (3) Penstock pipe 106 JPY 38 38 38 38 38 38 275 275 275 275 275 275 275 38 38 38 38 38 38 Unit weight W=ａ＊Ｘ+ｂ ｔ/ｍ 0.23 0.23 0.23 0.23 0.23 0.23 0.38 0.38 0.38 0.38 0.38 0.38 0.38 0.24 0.24 0.24 0.24 0.24 0.24 a 0.0026 b 0.20640 Weight ｔ 5.7 5.7 5.7 5.7 5.7 5.7 106.1 106.1 106.1 106.1 106.1 106.1 106.1 5.9 5.9 5.9 5.9 5.9 5.9 Unite price 103 JPY/t 1,511 1,511 1,511 1,511 1,511 1,511 982 982 982 982 982 982 982 1,500 1,500 1,500 1,500 1,500 1,500 Y=a*Xｂ a 1950 b -0.147 (4) Penstock(w.o penstock pipe) 106 JPY 9 9 9 9 9 9 45 45 45 45 45 45 45 6 6 6 6 6 6 Unite price 103 JPY/m 357 357 357 357 357 357 162 162 162 162 162 162 162 257 257 257 257 257 257 Y=a*Xｂ a 357 b 1.14 (5) Outlet(Non pressure type) 106 JPY 23 22 21 19 17 15 14 13 12 11 11 10 8 15 14 14 13 11 10 X=r*Q 8 7 6 5 4 3 2.25 2 1.75 1.5 1.25 1 0.75 3 2.625 2.25 1.875 1.5 1.125 Y=a*Xｂ a 9.54 b 0.432 (6) Outlet channel 106 JPY 17 16 15 14 13 11 13 13 12 11 10 9 8 13 12 11 10 9 8 Y=√(B・H）＝a*Xb 2.40 2.28 2.15 2.01 1.84 1.65 1.93 1.84 1.75 1.65 1.54 1.42 1.27 1.84 1.75 1.65 1.54 1.42 1.27 a 1.09 ｂ 0.379 Y=a*Xｂ a 122 103 JPY/m 345 325 303 279 253 222 266 253 238 222 204 185 162 253 238 222 204 185 162 ｂ 1.19 sub total((1)～(6)) 87 85 83 80 77 73 459 449 440 429 418 406 393 72 70 69 67 65 62 （7) other work(=sub-total*0.05) 4 4 4 4 4 4 23 22 22 21 21 20 20 4 4 3 3 3 3 2.2.2 Mechanical equipment 106 JPY 10 8 7 5 4 2 37 31 25 20 15 11 7 6 5 4 3 2 1 (1) Mechanical equipment(above ground type)foundation X=Q*He2/3*n1/2 31 28 24 20 16 12 74 66 58 50 41 33 25 21 19 16 13 11 8 Y=a*Xｂ a 0.0595 b 1.49 Sub total(2.2～2.3) 106 JPY 102 98 93 89 84 79 518 503 487 471 455 438 420 81 78 76 73 70 67 2.2.3 Related appratus(3%) 106 JPY 3 3 3 3 3 2 16 15 15 14 14 13 13 2 2 2 2 2 2 2.3 Electrical equipment 106 JPY 362 329 294 258 219 178 499 462 424 384 341 295 245 259 235 210 184 156 127 X=Pmax/He1/2 166 145 125 104 83 62 285 253 222 190 158 127 95 104 91 78 65 52 39 Tubular a 8.9000 b 0.7250 Francis a 12.8000 b 0.6480 2.4 Cost for temporary facilities 48 44 40 36 31 27 109 103 97 91 84 77 70 35 33 30 27 23 20 （2.1+2.2+2.3）×0.1 2.5 General expense 69 63 57 51 45 38 155 147 138 130 120 110 100 51 47 42 38 34 29 (2.1+2.2+2.3+2.4)×0.13 2 Annual generation ΣP Mwh 1,219 1,195 1,131 1,032 900 724 3,749 3,793 3,801 3,770 3,675 3,479 3,171 609 595 563 511 443 358 Unit construction cost JPY/kwh 490 459 441 432 433 456 360 337 317 299 285 276 274 721 680 655 649 658 696 PHP/kwh 228 214 205 201 201 212 167 157 147 139 132 128 127 336 316 305 302 306 324

Attachment 7 4.4 Operation＿D

Diversion Diversion Diversion Diversion Diversion Diversion Diversion Bayongan Bayongan Bayongan Bayongan Bayongan Bayongan Malinao＿1 Malinao＿2 Malinao＿3 Malinao＿4 Malinao＿5 Malinao＿6 shute_1 shute_2 shute_3 shute_4 shute_5 shute_6 shute_7 ＿1 ＿2 ＿3 ＿4 ＿5 ＿6 1. Design condition Pmax Pmax kw 462 404 347 289 231 173 2,336 2,077 1,817 1,557 1,298 1,038 779 361 316 271 226 181 136 Max. discharge Qmax m3/s 8.00 7.00 6.00 5.00 4.00 3.00 4.50 4.00 3.50 3.00 2.50 2.00 1.50 4.00 3.50 3.00 2.50 2.00 1.50 Average discharage Qave m3/s 3.82 3.68 3.45 3.15 2.77 2.29 1.21 1.18 1.14 1.09 1.02 0.93 0.74 1.31 1.24 1.14 1.00 0.85 0.67 Annual Generation ΣP Mwh 993 974 924 847 744 606 4,606 4,665 4,694 4,682 4,617 4,491 3,656 739 725 690 630 549 446 Effective head He ｍ 7.8 7.8 7.8 7.8 7.8 7.8 67.2 67.2 67.2 67.2 67.2 67.2 67.2 12.3 12.3 12.3 12.3 12.3 12.3 Penstock diameter D ｍ 2.0 2.0 2.0 2.0 2.0 2.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.5 1.5 1.5 1.5 1.5 1.5 Water way Radius r ｍ 1.0 1.0 1.0 1.0 1.0 1.0 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.8 0.8 0.8 0.8 0.8 0.8 Penstock length Lp ｍ 25.0 25.0 25.0 25.0 25.0 25.0 280.0 280.0 280.0 280.0 280.0 280.0 280.0 25.0 25.0 25.0 25.0 25.0 25.0 Outlet channel length Lo ｍ 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 Turbine type Tubular Tubular Tubular Tubular Tubular Tubular Francis Francis Francis Francis Francis Francis Francis Tubular Tubular Tubular Tubular Tubular Tubular Number of turbine n 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 above above above above above above above above above above above above above above above above above above above Power house type ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground ground 2. Construction cost(total) 106 JPY 597 548 498 445 389 330 1,349 1,277 1,203 1,126 1,046 960 868 436 402 366 329 290 248 1PHP= 2.15 JPN 106 PHP 278 255 231 207 181 153 627 594 560 524 486 447 404 203 187 170 153 135 115 2.1 Architecture(Power house ) 106 JPY 14 12 11 9 8 6 52 48 43 37 32 27 21 11 10 9 8 6 5 Y=a*Xｂ a 0.084 ｂ 0.83 2.2 Civil work 105 101 96 91 87 82 534 518 501 485 468 451 433 84 81 78 75 72 69 2.2.1 Water way 92 89 87 84 81 77 482 472 462 451 439 427 413 75 74 72 70 68 65 (1) Intake 106 JPY 0 0 0 0 0 0 30 28 26 24 22 20 17 0 0 0 0 0 0 (Non.pressure type） X=r*Q 2.25 2 1.75 1.5 1.25 1 0.75 Y=a*Xｂ a 19.7 b 0.506 106 JPY (2) Head tank 82 76 69 62 55 48 39 X=Q Y=a*Xｂ a 29.9 b 0.669 (3) Penstock pipe 106 JPY 38 38 38 38 38 38 275 275 275 275 275 275 275 38 38 38 38 38 38 Unit weight W=ａ＊Ｘ+ｂ ｔ/ｍ 0.23 0.23 0.23 0.23 0.23 0.23 0.38 0.38 0.38 0.38 0.38 0.38 0.38 0.24 0.24 0.24 0.24 0.24 0.24 a 0.0026 b 0.20640 Weight ｔ 5.7 5.7 5.7 5.7 5.7 5.7 106.1 106.1 106.1 106.1 106.1 106.1 106.1 5.9 5.9 5.9 5.9 5.9 5.9 Unite price 103 JPY/t 1,511 1,511 1,511 1,511 1,511 1,511 982 982 982 982 982 982 982 1,500 1,500 1,500 1,500 1,500 1,500 Y=a*Xｂ a 1950 b -0.147 (4) Penstock(w.o penstock pipe) 106 JPY 9 9 9 9 9 9 45 45 45 45 45 45 45 6 6 6 6 6 6 Unite price 103 JPY/m 357 357 357 357 357 357 162 162 162 162 162 162 162 257 257 257 257 257 257 Y=a*Xｂ a 357 b 1.14 (5) Outlet(Non pressure type) 106 JPY 23 22 21 19 17 15 14 13 12 11 11 10 8 15 14 14 13 11 10 X=r*Q 8 7 6 5 4 3 2.25 2 1.75 1.5 1.25 1 0.75 3 2.625 2.25 1.875 1.5 1.125 Y=a*Xｂ a 9.54 b 0.432 (6) Outlet channel 106 JPY 17 16 15 14 13 11 13 13 12 11 10 9 8 13 12 11 10 9 8 Y=√(B・H）＝a*Xb 2.40 2.28 2.15 2.01 1.84 1.65 1.93 1.84 1.75 1.65 1.54 1.42 1.27 1.84 1.75 1.65 1.54 1.42 1.27 a 1.09 ｂ 0.379 Y=a*Xｂ a 122 103 JPY/m 345 325 303 279 253 222 266 253 238 222 204 185 162 253 238 222 204 185 162 ｂ 1.19 sub total((1)～(6)) 87 85 83 80 77 73 459 449 440 429 418 406 393 72 70 69 67 65 62 （7) other work(=sub-total*0.05) 4 4 4 4 4 4 23 22 22 21 21 20 20 4 4 3 3 3 3 2.2.2 Mechanical equipment 106 JPY 10 8 7 5 4 2 37 31 25 20 15 11 7 6 5 4 3 2 1 (1) Mechanical equipment(above ground type)foundation X=Q*He2/3*n1/2 31 28 24 20 16 12 74 66 58 50 41 33 25 21 19 16 13 11 8 Y=a*Xｂ a 0.0595 b 1.49 Sub total(2.2～2.3) 106 JPY 102 98 93 89 84 79 518 503 487 471 455 438 420 81 78 76 73 70 67 2.2.3 Related appratus(3%) 106 JPY 3 3 3 3 3 2 16 15 15 14 14 13 13 2 2 2 2 2 2 2.3 Electrical equipment 106 JPY 362 328 294 257 219 178 499 462 424 384 341 295 245 256 233 208 182 155 126 X=Pmax/He1/2 166 145 124 104 83 62 285 253 222 190 158 127 95 103 90 77 64 52 39 Tubular a 8.9000 b 0.7250 Francis a 12.8000 b 0.6480 2.4 Cost for temporary facilities 48 44 40 36 31 27 109 103 97 91 84 77 70 35 32 29 26 23 20 （2.1+2.2+2.3）×0.1 2.5 General expense 69 63 57 51 45 38 155 147 138 130 120 110 100 50 46 42 38 33 29 (2.1+2.2+2.3+2.4)×0.13 2 Annual generation ΣP Mwh 993 974 924 847 744 606 4,606 4,665 4,694 4,682 4,617 4,491 3,656 739 725 690 630 549 446 Unit construction cost JPY/kwh 601 563 539 525 523 544 293 274 256 241 226 214 237 591 554 531 523 528 556 PHP/kwh 280 262 251 244 243 253 136 127 119 112 105 99 110 275 258 247 243 246 259

Attachment 7