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was no question of doing that as the previous raising had put paid to that possibility. So the

team came up with a brilliant solution: they would put a step in the reservoir by constructing
a separate embankment dam at a narrow point halfway along its length. (Fig. 3.39.) This

upper dam would serve a dual purpose: it would not only increase the efficiency of the
generating system, but it would also effectively double the capacity of the original Steenbras

reservoir. The construction was completed in 1979, and so the first hydroelectric pumped
storage scheme to be constructed in Africa came into being, while the Cape Town water

supply received another boost.

This was still not the end of the story, as the success of the Steenbras Pumped Storage

Scheme persuaded the Department of Water Affairs to go ahead with a similar but much

larger project on the nearby Palmiet River and some of the water from this scheme flows into
Steenbras and thus adds to the available stock. Pumped storage schemes are seen as an

effective and eco-friendly way of coping with short term surges in demand, and are now used
in bigger schemes in the Drakensberg.

The Last Big Dam in the Cape

Tom Stewart’s third option of a dam on the Berg River near Franschhoek eventually saw the
light of day in 2007 when the huge Berg River Scheme was completed. (Fig. 3.40.) This

structure was carefully engineered taking into account possible earthquake activity, and
equally importantly it includes special features to ensure that the environment of the river

downstream is protected. A sophisticated overflow system, in which Ninham Shand’s son

Mike had a major hand, allows floods in the catchment to be mimicked thus preserving the
ecosystems in the lower reaches.

This facility will assure Greater Cape Town of adequate water supplies until about 2022. But

there are no new dam sites on the Cape Town side of the Hottentots Holland Mountains and

thereafter other means will have to be found to provide for the needs of the city. Water
demand management systems are already in place, while re-use of effluent and the

management of aquifers is underway. It seems that the desalination of seawater will be the
eventual solution, and great strides have been made in other parts of the world to develop an

efficient process. But current solutions are very expensive, and hungry for electricity, so