Sustainable use of the world's freshwater resources requires that socio-economic and hydro-environmental systems be viewed as mutually dependent. In Africa, the United Nations promotes these principles by assisting countries establish a framework for integrated management and protection of transboundary watercourses essential to national development.
The Okavango River Basin is shared by three nations - Angola, Botswana, and Namibia. The basin straddles sub-humid climatic zones in Angola through semi-arid to arid climatic zones in northern Namibia and Botswana where freshwater sources are scarce. The Okavango River Basin remains one of the least human impacted basins on the African continent. Mounting socio-economic pressures on the basin in the riparian countries, Angola, Botswana and Namibia, threaten to change its present character. It is anticipated that in the long-term this may result in irretrievable environmental breakdown and consequent loss of domestic and global benefits.
The United Nations Department of Economic and Social Affairs (UNDESA) is assisting the riparian countries maintain these benefits which requires agreement over the sharing of both the benefits and associated liabilities (to include those of an environmental and ecological nature) through joint management of the basin's water resources. To do this UNDESA is supporting The Permanent Okavango River Basin Commission (OKACOM) which was established in September 1994 with a declared political agreement to work toward joint management of the basin. The 1994 OKACOM Agreement, the 1995 SADC Protocol on Shared Watercourse Systems and the 1997 UN Convention on the law of the non-navigational uses of international watercourses provide a framework for such an agreement. Under the OKACOM Agreement, the riparian countries are working toward the implementation of an Integrated Management Plan (IMP) for the basin on the basis of an Environmental Assessment (EA). At the request of UNDP, UNDESA has been providing technical assistance to OKACOM since 1995 in preparing a transboundary diagnostic analysis of the basin and mobilising funding through the Global Environmental Facility (GEF) and other bi-lateral donors.
The basin's source in the Angolan Province of Cuando Cubango is relatively undeveloped with few wholesale water demands made upon the watercourses of the source sub-basins, the Cubango and Cuito. As the main tributaries converge on and run along the border with northern Namibia, human development alongside the trunk water course intensifies. In Botswana, the ORB drains into the Kalahari desert as an alluvial fan, commonly known as the Okavango Delta which forms part of a large national wetland reserve. Periodic outflows from the apex of the fan to the Chobe channel linked to the Zambezi basin occur but the bulk of the flow drains to the distal margin of fan which is bounded by geological faults across which flood flows intermittently drain and flow into the Boteti river to evaporate in the Makgadikagadi basin.