Opening date 1897 Type of dam Masonry gravity dam Length 277 m (909 ft) Height 50 m Spillway capacity 20 m3/s (706 ft3/s) | Owner(s) Cape Town Municipality Impounds Disa Stream Spillway type Free overspill Surface area 13 ha Construction began 1894 | |
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Location Table Mountain, Western Cape, South Africa Total capacity 927,000 m3 (32,737,000 cu ft) Similar Orange Kloof, Kasteelspoort, Molteno Dam, Nursery Ravine, Platteklip Gorge | ||
Woodhead Dam is a dam on Table Mountain, Western Cape, South Africa. It was built in 1897 and supplies water to Cape Town. The dam, which was the first large masonry dam in South Africa, was designated as an International Historic Civil Engineering Landmark by the American Society of Civil Engineers in 2008.
Contents
Map of Woodhead Dam, Table Mountain (Nature Reserve), Cape Town, South Africa
History
In 1870, the growth of Cape Town led to shortages of drinking water. It was decided to build a reservoir on Table Mountain to provide water to the city. Scottish hydraulic engineer Thomas Stewart was engaged to design and build the reservoir.
The Woodhead Tunnel was built between 1888 and 1891. It was used to divert the Disa Stream, a tributary of the Hout Bay River, westward to provide water for the reservoir.
An aerial cableway was constructed to transport men and materials to the construction site. The dam was constructed between 1894 and 1897. This dam was followed by four others in the area. The Hely-Hutchinson Dam and reservoir was built by 1904 just upstream of the Woodhead reservoir. The Alexandra Dam and Victoria Dam were built on the original Disa Stream by 1903. The last of the five dams was the De Villiers Dam in 1907. This was built downstream of the Alexandra and Victoria Dams. Today, these five dams supply around 15% of the water for Cape Town.
Design
The Woodhead Tunnel is 640 m (2,100 ft) long. The Woodhead Dam is a masonry gravity dam that is 277 m (909 ft) long and 50 m (164 ft) high. It has a free overspill spillway with a capacity of 20 m3/s (706 ft3/s). The reservoir has a capacity of 927,000 m3 (32,737,000 cu ft) and a surface area of 13 hectares (32 acres).