Sri Lanka: DRY ZONE URBAN WATER and SANITATION PROJECT - for Vavuniya Per Aru Reservoir
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Environment Impact Assessment Report Project Number: 37381-013 November 2012 Sri Lanka: DRY ZONE URBAN WATER AND SANITATION PROJECT - for Vavuniya Per Aru Reservoir Prepared by Project Management Unit for Dry Zone Urban Water and Sanitation Project, Colombo, Sri Lanka. For Water Supply and Drainage Board Ministry of Water Supply and Drainage, Sri Lanka. This report has been submitted to ADB by the Ministry of Water Supply and Drainage and is made publicly available in accordance with ADB’s public communications policy (20011). It does not necessarily reflect the views of ADB. THE DEMOCRATIC SOCIALIST REPUBLIC OF SRI LANKA MINISTRY OF WATER SUPPLY AND DRAINAGE NATIONAL WATER SUPPLY AND DRAINAGE BOARD ENVIRONMENTAL IMPACT ASSESSMENT ON THE PROPOSED SURFACE WATER EXTRACTION FROM A RESERVOIR ACROSS PER ARU VAVUNIYA DISTRICT November 2012 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir ABBREVIATIONS ADB = Asian Development Bank APs = Affected People BCR = Benefit Cost Ratio BOD = Biological Oxygen Demand BOP = Blocking out Plans CBO = Community Based Organization COD = Chemical Oxygen Demand DCSMS = Design, Construction, Supervision and Management Support DFC = Department of Forest Conservation DFO = Divisional Forest Officer DOA = Department of Agriculture DS = Divisional Secretary DWC = Department of Wildlife Conservation DZ = Dry Zone EC = Electrical Conductivity EMU = Environmental Management Unit FD = Forest Department FOs = Farmer Organizations FR = Forest Reserve FSL = Full Supply Level GA = Government Agent GDP = Gross Domestic Product GIS = Geographical Information Systems GN = Grama Niladhari – A village Headman GPS = Global Positioning System GSMB = Geological Survey and Mines Bureau ha. = Hectare HBPL = Household Population below poverty line IEE = Initial Environmental Examination IRR = Internal Rate of Return IUCN = International Union for Conservation of Nature JICA = Japan International Cooperation Agency LAA = Land Acquisition Act LARC = Land Acquisition & Resettlement Committees National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir LGA = Local Government Authority LHG = Low Humic Gley Soils MASL = Mahaweli Authority of Sri Lanka MCM = Millions of Cubic Meters MSL = Mean Sea Level MSW = Municipal Solid Waste NCP = North Central Province NEA = National Environmental Act NGO = Non Governmental Organization NIRP = National Involuntary Resettlement Policy NP = National Park NPV = Net Present Value NWSDB = National Water Supply and Drainage Board O&M = Operations and Maintenance OFC = Other Field Crops PD = Project Director RBE = Reddish Brown Earths RE = Resident Engineer RIP = Resettlement Implementation Plan RIS = Reservoir Induced Seismicity SIA = Social Impact Assessment SLS = Sri Lanka Standards SPM = Small Particulate Matter SPM = Suspended Particulate Matter SWM = Solid Waste Management TDS = Dissolved Solids TOR = Terms of Reference UNDP = United Nations Development Programme WRB = Water Resources Board WTP = Water Treatment Plant National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir CONTENTS EXECUTIVE SUMMARY EXECUTIVE SUMMARY ............................................................................................................................ I A. BACKGROUND .............................................................................................................................. I B. PROJECT CONFIGURATION ............................................................................................................... I C. PROJECT IMPACT AREA AND THE STUDY AREA ....................................................................................... I D. PROJECT JUSTIFICATION .................................................................................................................. II E. PHYSICAL AND BIOLOGICAL ENVIRONMENT .......................................................................................... II F. SOCIO ECONOMIC ENVIRONMENT .................................................................................................... III G. ARCHAEOLOGICAL AND CULTURAL CONSIDERATIONS ............................................................................ IV H. KEY ENVIRONMENTAL IMPACTS AND MITIGATORY MEASURES ................................................................. IV I. ENVIRONMENTAL MANAGEMENT AND MONITORING PLAN ..................................................................... VI J. CONCLUSION AND RECOMMENDATION.............................................................................................. VI I. INTRODUCTION .............................................................................................................................. 1 A. BACKGROUND OF THE PROJECT ....................................................................................................... 1 B. OBJECTIVES AND JUSTIFICATION OF THE PROJECT ................................................................................. 1 C. OBJECTIVE OF THE EIA REPORT ....................................................................................................... 1 D. METHODOLOGIES AND TECHNOLOGIES ADOPTED FOR PREPARATION OF THE EIA REPORT .............................. 2 1. Survey of existing literature 2 2. Field investigations 3 3. Geological investigations 4 4. Soil study 4 5. Study on surface water quality 4 6. Study on ground water quality 4 7. Study on air quality 4 8. Study on noise and vibration 5 9. Observations on archaeology 5 10. Spatial data 5 11. Non‐spatial data 5 E. GOVERNMENT POLICY REGARDING THE PROJECT .................................................................................. 5 F. CONFORMITY WITH OTHER DEVELOPMENT PLANS IN THE AREA ............................................................... 7 II. DESCRIPTION OF THE PROPOSED PROJECT AND REASONABLE ALTERNATIVES ................................. 9 A. DESCRIPTION OF THE PROJECT ......................................................................................................... 9 1. Name and location of the project area 9 2. Key feature of the proposed project 9 3. Temporary constructions and construction material 15 4. Methodology of construction of Per Aru reservoir 15 5. Methodology of operation 19 6. Workforce requirements 19 7. Phased implementation plan of the project 19 8. Total project cost, investment and funding sources 19 B. EVALUATION OF ALTERNATIVES ..................................................................................................... 21 National Water Supply and Drainage Board EIA Study of the Per Aru Reservoir 1. No action alternative 21 2. Site alternatives 21 3. Design alternatives 22 III. DESCRIPTION OF THE EXISTING ENVIRONMENT ............................................................................ 25 A. TOPOGRAPHY AND THE STUDY AREA ............................................................................................... 25 B. PHYSICAL ENVIRONMENT ............................................................................................................. 31 1. Geology 31 2. Geotechnical condition 32 3. Leakage conditions 35 4. Agro‐ecological regions 35 5. Land suitability 37 6. Climate of the low country dry zone 37 7. Mineral resources 38 8. Rainfall 41 9. Temperature 42 10. Evaporation 42 11. Hydrology 43 12. Groundwater 51 13. Land use 58 14. Air quality and noise 63 C. BIOLOGICAL ENVIRONMENT .......................................................................................................... 66 1. Proximity to wildlife reserves and forest reserves 66 2. Ecological status of the project area 71 3. Per Aru upper catchment area 73 4. Inundated area and downstream of the Dam 79 5. Species habitat of potential resettlement land for inundated agricultural lands 97 D. HUMAN SETTLEMENT AND LAND USE ............................................................................................ 101 1. Settlement of the affected population 101 2. Population characteristics of the affected population 101 3. Income generation sources and patterns 104 4. Present water supply and water uses 108 5. Culture and historical aspiration of the affected people 110 6. Existing infrastructure facilities. 110 7. Reported environmental incidents 110 IV. ANTICIPATED ENVIRONMENTAL IMPACTS .................................................................................... 111 A. IMPACTS ON SOIL AND TOPOGRAPHY ............................................................................................ 111 B. IMPACTS ON HYDROLOGY AND WATER QUALITY ............................................................................... 111 1. Changes in surface water flow 111 2. Changes of groundwater table 111 3. Favorable aspects of impoundment 112 4. Water pollution due to machinery and site activities 112 5. Impacts on surface water quality (operation phase) 112 C. IMPACTS OF AIR POLLUTION ........................................................................................................ 112 D. IMPACTS OF NOISE AND VIBRATION .............................................................................................. 113 E. ECOLOGICAL IMPACTS ............................................................................................................... 115 1. Impacts onterrestrial fauna and flora due to habitat losses 115 2. Impacts on aquatic fauna and flora due to the project. 116 3. Impacts on nearby forest reserves (if any) 117 4. Impacts on nearby wildlife reserves and wildlife migration 117 National