Daan Viljoen
In 1954, the Gobabis Municipality requested the SWA Administration to build a dam in the Black Nossob River as the municipal boreholes, the town's sole source of water, could no longer supply the needs of Gobabis. In response to this request, the Daan Viljoen Dam was built near the town and officially opened by the Administrator on 18 August 1956. Two years later it was raised to increase its capacity to the current 0.4 Mm³.
Tilda Viljoen
The Daan Viljoen Dam was only a short-term solution to the problem, and in 1964 the Administration built the Tilda Viljoen Dam, a pumped storage dam with a capacity of 1,25 Mm³. Since the Tilda Viljoen Dam has no natural source of inflow, water is transferred into it from the Daan Viljoen Dam on account of its better basin characteristics.