KAWA MULTIMEDIA PUBLICATIONS
The Volta river project in Ghana (Akosombo dam)
One of the very first multi-purpose river projects in Africa was the Volta River Project. Ever since the old colonial days back in the 1920's control of the highly seasonal River Volta at Akosombo has been considered desirable. It was not until independence in 1957 however, that the then Prime Minister Dr. Nkrumah persuaded the World Bank, the U.S.A. and the U.K. to invest in the project.
The need for control was great. The River Volta's many sources are found in the dry plateau lands of the interior around Bobo Dioulasso and Ouagadougu in Upper Volta, There is only one rainy season in these tropical continental lands and at times the river used to nearly dry up. To obtain electricity Ghana had to use thermal power stations which necessitated spending valuable foreign exchange on oil imports. The dam was started in 1963 and opened three years later. It was built at the village of Akosombo, about 100 kilometres from the sea where the valley "was at its narrowest. Like the Aswan Dam it is a rock/ill dam. About 8000000 cubic metres of rock and rubble were used in its construction, all of which is lined with thick layers of concrete. It is 134 metres high and 426 metres wide at the base of the main dam. The complex includes a power dam and station on the west bank and a flood control dam and saddle dam on the east bank. The saddle dam plugged a further gap not covered by the main dam when the waters rose.
Six huge pipes known as penstocks lead water from the headrace down into six turbines, each capable of producing 150 megawatts when power production reached its maximum in 1979. From the generators water is led through the tailrace back into the Volta and so to the sea.
Lake Volta is the man-made lake which has risen behind the dam. In the rainy season the lake rises and the gates of the flood control dam have to be opened to stop water flowing over the top.
The need for control was great. The River Volta's many sources are found in the dry plateau lands of the interior around Bobo Dioulasso and Ouagadougu in Upper Volta, There is only one rainy season in these tropical continental lands and at times the river used to nearly dry up. To obtain electricity Ghana had to use thermal power stations which necessitated spending valuable foreign exchange on oil imports. The dam was started in 1963 and opened three years later. It was built at the village of Akosombo, about 100 kilometres from the sea where the valley "was at its narrowest. Like the Aswan Dam it is a rock/ill dam. About 8000000 cubic metres of rock and rubble were used in its construction, all of which is lined with thick layers of concrete. It is 134 metres high and 426 metres wide at the base of the main dam. The complex includes a power dam and station on the west bank and a flood control dam and saddle dam on the east bank. The saddle dam plugged a further gap not covered by the main dam when the waters rose.
Six huge pipes known as penstocks lead water from the headrace down into six turbines, each capable of producing 150 megawatts when power production reached its maximum in 1979. From the generators water is led through the tailrace back into the Volta and so to the sea.
Lake Volta is the man-made lake which has risen behind the dam. In the rainy season the lake rises and the gates of the flood control dam have to be opened to stop water flowing over the top.