The R1,5-billion Berg River Dam, which adds almost 20% of capacity to Cape Town’s water supply, is officially open.
The new dam, which was opened on 5 March 2009 by President Kgalema Motlanthe, is the biggest of its type in South Africa. It has a storage capacity of 130 million cubic metres, which increases the city’s raw water storage capacity from 768 to 898 million cubic metres per year.
The dam is situated in the upper reaches of the Berg River catchment area. It consists of an embankment of rock mined from the river bed and surrounding area, with an impermeable 350mm layer of concrete on the upstream side. The dam’s wall is 67 metres high and 928 metres long.
The Berg River Dam is the first dam in South Africa to be designed, built and operated in accordance with the guidelines of the United Nations World Commission on Dams.
The project, which comprises the dam, a supplement scheme, two pump stations and 12 km of pipeline, is financed through a partnership between the City, the Department of Water Affairs and Forestry (DWAF), and the Trans-Caledon Tunnel Authority (TCTA). DWAF approval for the project was dependent on the City reducing its water demand by 20%. The City is implementing a water conservation and demand management strategy and is well ahead of this target, with a 25% saving on anticipated usage.
Public and commercial participation in saving water is central to this strategy. Although the dam will alleviate immediate water shortages, it is imperative that residents, agriculture and businesses continue to use water sparingly and recycle where possible, given the Western Cape’s arid nature.
Cape Town has six supply dams, the largest being the Theewaterskloof dam between Franschoek and Villiersdrop which has a capacity of 480,000Ml while the smallest is Steenbras Upper, which has a capacity of 31,767Ml.