The (thirsty) story behind the Table Mountain dams

Woodhead Dam was built between 1893 and 1897 and was the first large dam to be built on Table Mountain. Designed to store water from the Disa catchment for supply to central Cape Town, it remains the largest of the five Table Mountain dams, and can hold 954 million litres of water. The final stone was lowered into place on 1 May 1897, in a formal ceremony attended by Cape Town mayor Sir John Woodhead. The dam wall measures 248 metres long and 38 metres high, and was built from sandstone quarried on the mountain. Many of the blocks weighed around two tons and were moved into place by steam-driven crane, the remnants of which can still be seen in the Waterworks Museum at the northern edge of the Hely-Hutchinson Reservoir.

To get men and materials onto the summit, engineer Thomas Stewart constructed a 665-metre aerial cableway from Victoria Road above Camps Bay to the top of Kasteelspoort. When completed, Woodhead was the first large masonry dam built in South Africa, and in 2008 it was named an International Historic Civil Engineering Landmark by the American Society of Civil Engineers.

City planners knew that Woodhead wouldn’t solve the problem, and work soon began on the Hely-Hutchinson Reservoir. Completed in 1904, it was built just above Woodhead, in the same catchment system. Named after former Cape Governor Sir Walter Hely-Hutchinson, the reservoir holds 925 megalitres, making it the second-largest of the five dams on the mountain. The sandy beaches at the eastern edge of the reservoir make it a popular spot for hikers to swim (even though this is officially prohibited by South African National Parks).

If you walk the jeep track from Constantia Nek to the Back Table, you’ll pass three smaller dams, all of which store water for the southern suburbs of Cape Town. The first you’ll come across is De Villiers Dam, completed in 1910 as the last of the five Table Mountain dams to be built. Named after Lord John Henry de Villiers, Chief Justice of the Cape Colony, and later the first Chief Justice of South Africa, its 243 megalitres make it the largest of the three southern dams.

Next up is the Alexandra Dam, which also formed part of the Wynberg supply scheme to keep the suburbs from going thirsty. Built to store runoff from the Back Table, it holds 126 megalitres, making it the smallest of the five Table Mountain dams. Who was Alexandra, you might be asking? We’re not entirely sure. It could have been for the second name (Alexandrina) of Queen Victoria, or Queen Alexandra, who was the wife of King Edward VII, and daughter-in-law of Queen Victoria. We’ll keep digging!

The last dam on this corner of the mountain also stored water off the eastern slopes to feed the southern suburbs. It’s named – you guessed it – for Queen Victoria, who was on the English throne when the dam was built in 1895. Holding just 128 megalitres, Cape Town could drink it dry in three hours.

On the northern end of the Hely-Hutchinson Reservoir wall, the Waterworks Museum tells the story of building the mountaintop dams. Indoors, you’ll find a small display of faded photographs, typewritten notes and press clippings, while outside, the massive cogs and steam-driven crane slowly rust away. Opening hours are hard to find, but contact SANParks if you really want to visit.

You can turn a day of exploring the mountaintop into an overnight adventure by booking the Overseers’ Cottage, which is rented out by SA National Parks. The cottage sleeps up to 16 hikers in reasonable comfort, but the real drawcard is the location on the eastern edge of the mountain, with spectacular city views below. It gets booked well in advance, so start planning.