Sterkfontein_Dam=The Sterkfontein Dam is situated in the very upper reaches of the Vaal Dam catchment, on the Nuwejaarspruit, a few kilometres from the edge of the Drakensberg Escarpment. The dam receives its water via the Tugela-Vaal Project which is a pumped-storage scheme involving the net transfer of up to 600 Mm³ of water from KwaZulu-Natal. The water from KwaZulu-Natal is stored in Sterkfontein Dam and released to the Vaal Dam via the Wilge River when needed. Due to the favourable climatic characteristics of Sterkfontein Dam, it is beneficial to store water in the deep cool Sterkfontein Dam and only release water to the shallow Vaal Dam when needed. The evaporation losses from Sterkfontein Dam are approximately 35 Mm³a, which represent approximately 10 percent of the losses that would be experienced from Vaal Dam for a similar volume.
Originally commissioned in 1977, the Sterkfontein Dam, was subsequently raised in 1980 to its current height of 93 m with a crest length of 3 060 m and a full supply capacity of 2 617 Mm³. At full supply, it has a surface area of only 70 km² which combined with an MAP of 800 mm and an annual evaporation of 1 300 mm makes it a highly efficient storage unit.
Image: DWAF (South Africa)