Given Namibia's mainly arid climate and absence of perennial rivers except along the northern and southern borders, water is a particularly precious resource and ensuring a reliable supply has consequently a high priority. This is particularly vital for the development of new mines and other industries with a high level of water demand, while maintaining and extending potable water supplies to the population as a whole. The severe drought which hit the country in early 1992 highlighted the vulnerability of large groups of Namibians-especially in remoter rural districts-to water shortages, and the importance of ensuring a balance of supply to people and to commercial undertakings.

Most rivers-including all those in the interior of the country-are ephemeral and carry water only when enough rain falls in their respective catchment areas, which usually occurs only for short periods. Because of the unreliability and unevenness of rainfall, considerable usage is made of resources contained in underground aquifers. Water is stored and distributed via pipelines and canals from dams, or directly drawn from rivers, boreholes acquifers and water reclamation works. The perennial rivers that rise in neighbouring countries- the Kunene, Okavango, Zambezi and Orange-have a much higher potential in comparison with inland sources and are likely to be drawn on increasingly in coming years.

Water demand

The demand for water from inland sources was estimated at 200 mn cubic metres in 1990 and is projected as rising to 300 mn cubic metres by the year 2000. This will exceed the sustainable yield from available inland sources throughout much of the country and water will need to be obtained in greater quantities from the border perennial rivers. This is already takes place on a limited scale in the north where larger centres are supplied by water carried by canal from the Kunene River. Present demand for water from perennial rivers is some 50 mn cubic metres per year and this is expected to rise sixfold to 300mn over the next few years, including water for large-scale irrigation. While this represents a substantial increase in terms of present consumption it would still account for only an estimated 0.5% of total normal annual flow of the rivers concerned. Bilateral consultations are held with Namibia's neighbours to ensure optimum utilisation; in 1991 a joint agreement with Angola was signed covering cooperation in the use of the Kunene River for both water supply and energy purposes.

Water supply

The Department of Water Affairs (DWA) is responsible for bulk water supplies, while water is distributed to domestic households and commercial users in urban areas by municipalities. There are already 126 bulk water supply schemes of varying capacities supplying around 82 mn cubic metres per year for domestic, irrigation and industrial purposes with total investment estaimated at R1.5 bn. The country's largest storage dam at Hardap near Marienthal, has a capacity of 300 mn cubic metres, about half the national total. Inland water supply can be divided into four distinct areas, the southern region, north-central region, central coastal region and northern region. The Fish River bisects the southern region with most economic activity in the proximity of the river and its larger tributaries. Some 40% of the river's potential is currently realised, and it should be able to support future development in this region. The major water supply for the north-central region, containing the capital, the Tsumeb/Kombat mines and most of Namibia's large cattle ranches, is via the Eastern National Water Carrier (ENWC) which comprises a number of dams and the groundwater resource of the Karstveld, near Grootfontein. However, existing inland sources will shortly become inadequate for this region; in order not to exhaust the groundwater resource, tapping the Okavango River via a 250 km pipeline from Grootfontein to Rundu is the most feasible option. Ensuring reliable supplies to the west-central coastal region, which includes Walvis Bay, Swakopmund, the Rossing and Navachab mines has always been problematic. Water is currently tapped from ancient alluvial acquifers of the ephemeral rivers that flow into the sea but a long term supply has still to be assured. Two alternatives under consideration are for a link up to the ENWC and/or the construction of a seawater desalination plant at the coast. A proposal for an aluminium smelter made by a group of Dubai-based investors in 1992 includes a desalination plant.

In the densely-populated central areas of northern Namibia saline groundwater conditions and unfavourable surface catchment sites make it vital to expand the distribution network and link it to a perennial source of supply such as the Kunene River. This would also provide the most feasible source for the highly prospective northwestern Kaokoveld, where mining developments would require reliable bulk water supply.

Operations and tariffs

Water tariffs vary according to location and pipeline amortisation as they are linked to the capital cost and maintenance of each separate water supply system. The standard tariff varied between 50-100 cents per cubic metre as of 1992. Major economically-viable undertakings are normally required to pay the full economic cost of their water consumption, however, a flexible approach is adopted depending on the circumstances of individual consumers. Where, for instance, there is a ready source from a ground dam in the vicinity, water can be offered to preferential rates to new users. An example of the cross-benefits that can ensue when a new development provides the economic justification for improving infrastructure are the arrangements made to supply water to the Navachab gold mine. This involved expenditure of R28 mn by the government on construction of an 85 km pipeline from the Swakopport Dam, but the pipeline also supplies water to the nearby towns of Karibib and Usakos. Navachab will ultimately pay R14 mn towards the capital cost of the pipeline by way of a fixed monthly tariff over and above normal consumption charges.

The broad operational policies of the DWA are: