The Orange-Fish Tunnel transports 22 cubic metres of water per second along 82km of underground aqueduct, from the Gariep Dam to the Great Fish River, emerging near Steynsburg north of Cradock. Completed in 1975, it is the source of some jaw-dropping statistics and odd stories.
- Nearly 2.5 million cubic metres of rock were removed during the tunnel excavation, the equivalent of two Empire State Buildings.
- While the tunnel was being built in the late 1960s and early 1970s, 14 000 tons of bulk cement was brought in every week to this remote area, first via 40-ton rail tankers to three small railway stations around the tunnel, and then trucked by road.
- Lining the tunnels evenly took 842 000 cubic metres of concrete.
- The tunnel diameter is 5.33 metres, roughly as wide as a train tunnel.
- There was a massive methane fire that raged during construction nearly 50 years ago. To this day, methane remains something of a hazard. As a result, only diesel bakkies are allowed into the tunnels.
- A special vehicle created to do inspections in the tunnel had a diesel engine, completely sealed electrics and had a cab at each end so it could be easily driven forward or back. A bicycle with a dynamo and a light was attached in case the vehicle had a problem and the driver could ride back through the tunnel. No one knows what has become of it.
- During the Anglo-Boer War, British soldiers set up a forward supply camp near Teebus koppie, where the tunnel now has its outlet. One of them climbed to the top but must have slipped and injured himself. The Orange-Fish Tunnel commemoration document of 1975 records: “His cries for help went unheeded, and after the war his skeleton was found on the summit picked clean by the vultures that circle ceaselessly above Teebus Kop at dawn and dusk.”
- The Gariep Dam was only the second dam to capture the Orange River’s water after the Buchuberg Dam near Groblershoop was built in the 1930s as a white poverty relief project.
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To book a visit or to find out more, contact the Gariep Scheme Manager on 051 754 0001/2. The tunnel is only empty for about 4 weeks every year, generally from June to mid-July. And if you go, remember to take gumboots, a strong torch, spare clothes just in case and a camera (with a powerful flash) of course. And owing to the methane levels, matches and cigarette lighters are strictly banned from the premises.
Words and Photography Julienne du Toit