The Grande Dixence dam, at the head of the Val d'Hérens in the canton of Valais in Switzerland, is at 285 metres (935 ft) high one of the world's tallest dams and the highest in Europe. It holds back a lake, the Lac des Dix, around 4 km (2.5 mi) long. When full, the lake is up to 284 metres (932 ft) deep and contains 400 million m³ (100 billion gal) of water.
The top of the dam is at an altitude of 2,365 metres (7,759 ft) in a steep mountain vall...
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The Grande Dixence dam, at the head of the Val d'Hérens in the canton of Valais in Switzerland, is at 285 metres (935 ft) high one of the world's tallest dams and the highest in Europe. It holds back a lake, the Lac des Dix, around 4 km (2.5 mi) long. When full, the lake is up to 284 metres (932 ft) deep and contains 400 million m³ (100 billion gal) of water.
The top of the dam is at an altitude of 2,365 metres (7,759 ft) in a steep mountain valley. Tunnels bring the water to three power stations in the Rhône valley over 1,800 metres (5,900 ft) below.
The dam is situated on the relatively small Dixence river, but collects a large amount of water thanks to a system of water supply tunnels over 100 km (60 mi) long bringing water from other rivers and valleys. Most of the water comes from glaciers which melt during the summer. The lake is usually full of water by late September, and is allowed to empty during the winter, reaching its lowest point around April.
The first Grande Dixence...
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