Akosombo Dam

The Akosombo Hydroelectric Project (Akosombo HEP), usually referred to as the Akosombo Dam, is a hydroelectric dam in southeastern Ghana. The dam is specifically located at the Akosombo gorge, on the Volta River. The construction of the dam resulted in the flooding of the Volta River Basin, and the subsequent creation of Lake Volta. Lake Volta is the world's largest man-made lake and covers about 3.6% of Ghana's total land area.

The primary purpose of the Akosombo HEP was to provide electricity for the Aluminum Industry. The Akosombo HEP was called "the largest single investment in the economic development plans of Ghana". Its original electrical output was 912 MWe, which was upgraded to 1020 MWe in a retrofit project that was completed in 2006.

The flooding of land to create the Lake Volta reservoir, displaced many people and had a significant impact on the environment.

In the beginning of 2007, there were concerns over the electricity supply from the dam due to lower water levels in the Lake Volta reservoir. Some sources say these are due to problems with drought that are a consequence of global warming. During Q3-Q4 of 2007, much of this concern was abated when heavy rain fell in the catchment area of Volta River.

Source
http://en.wikipedia.org/wiki/Akosombo_Dam