PAK BENG HYDROPOWER PROJECT Transboundary Environmental and Social Impact Assessment & Cummulative Impact Assessement SEP 2015 Mekong Pak Beng Hydropower Project Transboundary Environmental and Social Impact Assessemnt & Cummulative Impact Assessement (TBESIA & CIA) - Final Report- May2013 Table of Contents 1 INTRODUCTION .......................................................................................................... 14 1.1 Background .............................................................................................................. 14 1.2 The Mekong River and the Mekong River Basin .......................................................... 16 1.3 Main Objective ......................................................................................................... 19 1.4 Framework and Scope of Investigation ........................................................................ 19 1.4.2 General Framework ............................................................................................ 19 1.4.3 Scope of Investigation ........................................................................................ 20 1.4.4 Study Zone ........................................................................................................ 21 1.5 Methodology ............................................................................................................ 22 1.5.2 Relevant Regulatory Framework in Lao PDR ....................................................... 22 1.5.3 Methology for Impact Assessment ....................................................................... 23 1.6 Limitations and Problem Solving in Data Collection ..................................................... 24 1.7 Policy and Legal Framework ...................................................................................... 25 1.7.1 Sustainable Hydropower Development ................................................................. 25 1.7.2 International Good Practice ................................................................................. 28 1.7.3 MRC Agreement ................................................................................................ 30 1.7.4 Relevant Environmental and Social Legislation in Lao PDR .................................. 31 1.8 Dams in the Lower Mekong Basin .............................................................................. 39 1.8.1 Mainstream Dams .............................................................................................. 39 1.8.2 Lower Mekong Dams ......................................................................................... 44 2 PAK BENG ENVIRONMENTAL PROJECT DESCRIPTION ....................................... 49 3 BASELINE OF ENVIRONMENTAL AND SOCIAL CONDITIONS .............................. 51 3.1 Mekong River Flows ................................................................................................. 51 3.1.1 General Background ........................................................................................... 51 3.1.2 Flows in the Main Stream ................................................................................... 55 3.2 Sedimentation ........................................................................................................... 78 3.2.2 Mekong River Basin .......................................................................................... 79 3.2.2 Sidementat Runoff Transport in the Mekong River ................................................ 80 3.3 Fish Migration and Fisheries ...................................................................................... 82 3.3.1 Fish Migration ................................................................................................... 82 3.3.2 Fisheries ........................................................................................................... 99 3.4 Navigation .............................................................................................................. 102 3.4.1 Waterway Transport ......................................................................................... 102 3.4.2 Transhipping Route and Period ......................................................................... 104 3.4.3 Probems Encountered and Future Development .................................................. 106 Pagei Mekong Pak Beng Hydropower Project Transboundary Environmental and Social Impact Assessemnt & Cummulative Impact Assessement (TBESIA & CIA) - Final Report- May2013 3.4.4 Agreements for Transhipping between Countries ................................................ 107 3.4.5 Transhipping in the study Area .......................................................................... 107 3.5 Water Quality ......................................................................................................... 114 3.5.2 Overview of water quality of the Lower Mekong Basin ....................................... 114 3.5.3 Further water quality details are as follows ......................................................... 115 3.5.4 Water Quality in the PBHPP Area ..................................................................... 118 3.6 Dam Safety ............................................................................................................. 122 3.7 Climate Change ...................................................................................................... 123 3.8 Social Baseline Condition ........................................................................................ 123 3.8.1 Social Overview of the Study Area and LMB Countries ...................................... 123 3.8.2 Social Condition in Zone 1 ............................................................................... 133 3.8.3 Social Condition in Zone 2 (Thai-Laos) ............................................................. 161 3.8.4 Social Condition in Zone 3 (Southern Laos) ....................................................... 180 3.8.5 Social Condition in Zone 4 (Cambodia and Tonle Sap Lake) ................................ 191 3.8.6 Social Condition in Zone 5 (Sounthern Vietnam and Mekong Delta) .................... 203 4 HYDROLOGY AND SEDIMENT CHANGED FROM THE PROJECT DEVELOPMENT 213 4.1 Development of Scenarios and Modeling Approach ................................................... 213 4.1.1 Background ..................................................................................................... 213 4.1.2 The PBHPP Development Scenarios (2017 and 2030) ......................................... 213 4.1.3 The Hydrologic Models .................................................................................... 216 4.2 Hydrological and Sedimentation Changes .................................................................. 222 4.2.1 Detail Analysis of Flow .................................................................................... 222 4.2.2 Details Analysis of Sedimentation ..................................................................... 228 5 TRANS-BOUNDARY AND CUMULATIVE IMPACT ASSESSMENT ........................ 242 5.1 Fish Migration and Fisheries .................................................................................... 242 5.1.1 Transboundary impact ...................................................................................... 242 5.1.2 Cumulative Impact ........................................................................................... 243 5.2 Navigation .............................................................................................................. 243 5.2.2 Transboundary impact ...................................................................................... 243 5.2.3 Cumulative Impact ........................................................................................... 244 5.3 Water Quality ......................................................................................................... 244 5.3.1 Transboundary impact ...................................................................................... 244 5.3.2 Cummulative Impact ........................................................................................ 246 5.4 Dam Safety ............................................................................................................. 247 5.5 Climate Change ...................................................................................................... 247 5.6 Social Impacts ........................................................................................................ 248 5.6.2 General Assumptions ....................................................................................... 248 Pageii Mekong Pak Beng Hydropower Project Transboundary Environmental and Social Impact Assessemnt & Cummulative Impact Assessement (TBESIA & CIA) - Final Report- May2013 5.6.3 Cummulative Social Impacts ............................................................................. 251 5.6.4 Transboundary Social Impacts .......................................................................... 257 6 MITIGATION AND MANAGEMENT INTERVENTIONS .......................................... 261 6.1 Project Level Mitigation .......................................................................................... 261 6.1.1 Hydrology ....................................................................................................... 261 6.1.2 Sidementation .................................................................................................