The Olifants River Basin, South Africa
The Olifants River passes through three provinces of South Africa (Gauteng, Mpumalanga, Northern Province), through the Kruger National Park, into Mozambique, where it joins the Limpopo. It is therefore a tributary of the Limpopo.
Average annual precipitation
Annual water quantities (supply and demand)
Supply: Mean Annual Runoff 1,992 million m3 
Demand: 976 million m3 (including hydropower). Estimated future demand 2010: 1,210 million m3
The river has been known to have zero flow during short periods as it enters Kruger Park.
Groundwater is an important source of water for many small towns, villages, small-scale farmers. Most of the groundwater exists in a relatively shallow weathered aquifer.
Altitudes range between 2300 m and 300 m at the Mozambique border.
Currently about 3.4 million, some living in urban areas with modern domestic water supply and sanitation systems, but most living in rural areas or towns with rudimentary or no formal domestic water supply system and no sanitation system.
- Agriculture, of which commercial and small scale irrigation is about 100,000 ha. Main crops are maize, cotton, vegetables, citrus, wheat, tobacco
- Forestry area: 71,500 ha
- The Kruger National Park is the largest in South Africa, with about 20,000 ha. (mostly in the basin)
There are over 2,500 dams, of which 30 are classified as major dams (>2 million m3).
Water users in the basin
- Urban: largely from the river
- Mining and industry: largely from the river, including small amounts imported from another basin. More than half of South Africa's electricity is generated in the Upper Olifants Basin.
Agriculture: largely from the river. There is a strong distinction between "commercial" farmers, who have relatively larger farms, sophisticated technologies, often grow high-value crops (e.g., citrus), most of which are for export, and "small-scale" farmers, most of whom are undercapitalized, with poor support services, lack good market access, and are struggling, as a result of the previous Apartheid policies and withdrawal of subsidies in recent years.
- Recreation: boating and fishing on river and in reservoirs.
- Environment: especially the National Park.
Existing and forecasted uses and concerns
At present water demand exceeds supply. Current projections show that water resources will be fully utilized by 2010. Consideration of reallocation among uses will therefore be necessary.
Water quality management will be an increasingly important issue in the future, largely because of existing mines, and pollution from closed mines.
Provision for the environmental demands through the implementation of a 'Reserve' to maintain the ecological integrity of the resource, is expected to have a significant effect on water availability for commercial uses.
- Possible expansion of small-scale irrigation to meet equity objectives may affect water availability for other sectors. Demand management will be essential.
- Overgrazing of the upper, middle and lower middle regions is already causing high silt loads, aggravated by the highly erodable soil types found here.
- Satisfying the legitimate demands of the downstream country (Mozambique) both for water supply, and in terms of occasional flood control and also salinity control near the Indian Ocean is likely to become a serious problem in the future.
Water policy and management issues
- Meeting human needs and environmental requirements as called for in the 1998 water law
- Demand management by commercial users
- Maintaining water quality
- Satisfying downstream requirements without threatening upstream uses which generate considerable economic wealth
Currently, the national Department of Water Affairs and Forestry is responsible for water resources management, including management of major infrastructure. Water Users Associations will take increasing responsibility for localized management of irrigation infrastructure and control structures, while water boards and local governments are responsible for the provision of domestic water services.
- Excellent in the Department of Water Affairs and Forestry and its consultants
- Excellent in universities and research institutes
- Mixed capacities at local levels
Data and models
There are considerable data and a number of models developed by consultants for the Department of Water Affairs and Forestry (DWAF), though there is a lack of specific information on these. Hydrological data are collected regularly by DWAF.