Projecting water demand and availability under climate change through the application of WEAP in the Nam Ngum downstream area, Laos by Phingsaliao Sithiengtham Student ID: 2176693 Supervisor: Strategic Professor Okke Batelaan Thesis submitted to Flinders University for the degree of Master of Science (Water Resources Management) College of Science and Engineering Adelaide, July 2019 TABLE OF CONTENTS LIST OF FIGURES ............................................................................................................................ iv LIST OF TABLES .............................................................................................................................. vi SUMMARY ....................................................................................................................................... vii DECLARATION ................................................................................................................................ ix ACKNOWLEDGEMENTS ................................................................................................................. x LIST OF ABBREVIATIONS ............................................................................................................. xi CHAPTER 1: INTRODUCTION ........................................................................................................ 1 1.1. Background and rationale ...................................................................................................... 1 1.2. Goal and Objectives .............................................................................................................. 3 1.3. Research questions ................................................................................................................ 3 1.4. Scope of study ....................................................................................................................... 4 1.5. Structure of the thesis ............................................................................................................ 4 CHAPTER 2: LITERATURE REVIEW ............................................................................................. 6 2.1. Water balance ........................................................................................................................ 6 2.2. Water allocation .................................................................................................................... 7 2.3. Climate change .................................................................................................................... 10 2.4. Lao water institutional and policy frameworks ................................................................... 14 2.4.1. Water institutional arrangements ................................................................................. 15 2.4.2. 8th National Socio-Economic Development Plan ........................................................ 16 2.4.3. Natural Resources and Environment Strategy 2025 .................................................... 17 2.4.4. Natural Resources and Environment Action Plan 2016-2020 ..................................... 17 2.4.5. Water and Water Resources Law 2017 ........................................................................ 18 2.5. Water Evaluation and Planning (WEAP) ............................................................................ 18 2.5.1. WEAP descriptions ...................................................................................................... 18 2.5.2. WEAP limitations ........................................................................................................ 20 2.5.3. Examples of WEAP ..................................................................................................... 20 CHAPTER 3: DATA AND METHODOLOGY ............................................................................... 23 3.1. Study area ............................................................................................................................ 23 3.2. Data description and analysis .............................................................................................. 27 3.2.1. Precipitation ................................................................................................................. 27 3.2.2. Temperature ................................................................................................................. 28 3.2.3. Wind speed ................................................................................................................... 28 3.2.4. Humidity ...................................................................................................................... 29 i 3.2.5. Sunshine and cloudiness fraction ................................................................................. 30 3.2.6. River flows ................................................................................................................... 31 3.2.7. Land use ....................................................................................................................... 32 3.2.8. Population .................................................................................................................... 33 3.2.9. Industrial units.............................................................................................................. 35 3.2.10. Digital Terrain Model .................................................................................................. 36 3.3. Methodology ....................................................................................................................... 36 3.3.1. Head flow ..................................................................................................................... 37 3.3.2. Catchment method ....................................................................................................... 37 3.3.3. Reservoir ...................................................................................................................... 39 3.3.4. Groundwater................................................................................................................. 40 3.3.5. Water use rates ............................................................................................................. 42 3.3.6. Demand sites ................................................................................................................ 44 3.3.7. Model calibration and validation ................................................................................. 45 3.3.7.1. Calibration ............................................................................................................ 45 3.3.7.2. Validation ............................................................................................................. 46 3.3.8. Scenarios simulations ................................................................................................... 47 CHAPTER 4: RESULTS AND DISCUSSION ................................................................................. 49 4.1. Model calibration and validation ......................................................................................... 49 4.2. Current water demand ......................................................................................................... 51 4.2.1. Agricultural water use .................................................................................................. 52 4.2.2. Domestic water use ...................................................................................................... 53 4.2.3. Industrial water use ...................................................................................................... 55 4.3. Current water availability .................................................................................................... 56 4.3.1. Water inflow ................................................................................................................ 58 4.3.2. Water outflow .............................................................................................................. 59 4.4. Groundwater and surface water interactions ....................................................................... 60 4.4.1. Groundwater recharge .................................................................................................. 60 4.4.2. Groundwater discharge ................................................................................................ 63 4.5. Future water demand and availability ................................................................................. 63 4.5.1. Increased water demand scenarios ............................................................................... 64 4.5.2. Climate change scenarios ............................................................................................. 66 4.5.3. Halved water inflow scenario ...................................................................................... 68 CHAPTER 5: CONCLUSION AND RECOMMENDATIONS ....................................................... 71 5.1. Conclusion ........................................................................................................................... 71 ii 5.2. Limitations........................................................................................................................... 73 5.3. Recommendations ..............................................................................................................