New Approaches to Adaptive Water Management under Uncertainty OOrraannggee RRiivveerr BBaassiinn Baseline Assessment Report Draft: November 2005 Compiled by: Nicci Diederichs, Dermot O’Regan, Caroline Sullivan, Mathew Fry, Myles Mander, Carla-Jane Haines & Margaret McKenzie NeWater_Orange River Basin_BAR_Draft-November2005. Incomplete, please do not quote Orange River Baseline Assessment Report 2 November 2005 NeWater_Orange River Basin_BAR_Draft-November2005. Incomplete, please do not quote Table of Contents STRATEGIC BASELINE SUMMARY ..................................................................................................................................... 7 SECTION A: BIOPHYSICAL CHARACTERISTICS........................................................................................................... 9 1. GEOGRAPHICAL & TOPOGRAPHICAL DESCRIPTION....................................................................................... 9 2. NATURAL ENVIRONMENT ......................................................................................................................................... 10 3. CLIMATE & HYDROLOGY.......................................................................................................................................... 15 3.1 RAINFALL, TEMPERATURE & EVAPORATION RATES ................................................................................................. 15 3.2 SURFACE FLOWS & PERIODICITY ............................................................................................................................... 16 3.3 GROUND WATER & AQUIFERS ................................................................................................................................... 19 3.4 DROUGHT & FLOODING REGIMES .............................................................................................................................. 20 SECTION B: HUMAN DEMANDS ON WATER RESOURCES ....................................................................................... 21 4. SOCIO-ECONOMIC STATUS ....................................................................................................................................... 21 4.1 ECONOMIC STATUS..................................................................................................................................................... 21 4.2 POPULATION STATUS.................................................................................................................................................. 22 4.2.1 South Africa........................................................................................................................................................... 23 4.2.2 Lesotho .................................................................................................................................................................. 23 4.2.3 Namibia ................................................................................................................................................................. 23 4.2.4 Botswana ............................................................................................................................................................... 23 5. WATER RESOURCE STATUS...................................................................................................................................... 24 5.1 DEVELOPMENT OF WATER RESOURCES ..................................................................................................................... 25 5.1.1 Impoundments ....................................................................................................................................................... 26 5.1.2 Water Transfer Schemes ....................................................................................................................................... 28 5.1.2.1 Orange River Project (ORP) .......................................................................................................................................... 28 5.1.2.2 The Lesotho Highlands Water Project (LHWP) ........................................................................................................... 35 5.2 WATER DEMAND & AVAILABILITY ........................................................................................................................... 38 5.2.1 South Africa........................................................................................................................................................... 40 5.2.1.1 The Vaal River ............................................................................................................................................................... 40 5.2.1.2 The Orange River........................................................................................................................................................... 41 5.2.2 Lesotho ................................................................................................................................................................. 42 5.2.3 Namibia ................................................................................................................................................................. 43 5.2.4 Botswana ............................................................................................................................................................... 44 5.3 WATER QUALITY AND ENVIRONMENTAL ISSUES ...................................................................................................... 44 5.3.1 Soil Erosion and Wetland Degradation ............................................................................................................... 45 5.3.2 Industrial and Municipal Pollution...................................................................................................................... 46 5.3.3 Water Quality Problems Associated with Agricultural Activities ....................................................................... 46 5.3.4 The State of the Orange River Estuary................................................................................................................. 47 5.3.5 Blackfly.................................................................................................................................................................. 48 5.4 PROJECTED FUTURE WATER REQUIREMENTS............................................................................................................ 48 SECTION C: GOVERNANCE & WATER RESOURCE MANAGEMENT .................................................................... 51 6. GOVERNANCE & MANAGEMENT OF WATER RESOURCES ........................................................................... 51 6.1 LEGAL & POLICY FRAMEWORKS FOR WATER RESOURCE MANAGEMENT ................................................................ 51 6.1.1 South Africa........................................................................................................................................................... 51 6.1.1.1 The National Water Act (NWA).................................................................................................................................... 52 6.1.1.2 The National Water Resource Strategy (NWRS).......................................................................................................... 52 6.1.2 Lesotho .................................................................................................................................................................. 52 6.1.3 Namibia ................................................................................................................................................................. 53 6.1.3.1 Water Act, 1968 ............................................................................................................................................................. 53 6.1.3.2 Borehole Act, 1956 ........................................................................................................................................................ 53 6.1.3.3 Waterworks Act (Act), 1962.......................................................................................................................................... 53 6.1.3.4 Water Utilities Corporation Act, 1970........................................................................................................................... 54 6.1.3.5 Namibian Water Resources Management Review (NWRMR)..................................................................................... 54 6.1.4 Botswana ............................................................................................................................................................... 54 Orange River Baseline Assessment Report 3 November 2005 NeWater_Orange River Basin_BAR_Draft-November2005. Incomplete, please do not quote 6.2 WATER RESOURCE MANAGEMENT AGENCIES........................................................................................................... 54 6.2.1 South Africa........................................................................................................................................................... 54 6.2.2 Lesotho .................................................................................................................................................................. 56 6.2.3 Namibia ................................................................................................................................................................