Mackenzie River Great Slave Lake, at Fort Resolution, Northwest Territories. The Slave is by far the largest river flowing into the lake, with an annual flow of 108 km (87 million acre-feet). It contributes about 77% of the overall inflow, and forms a large delta where it enters the lake. Other rivers entering Great Slave Lake area the Taltson, Lockhart and Hay Rivers, the latter of which also extends into Alberta and BC. The Mackenzie River issues from the western end of Great Slave Lake about south-west of Yellowknife. The channel is initially several kilometres wide but narrows to about at Fort
Lake Volta Dam holds back both the White Volta River and the Black Volta River, which formerly converged where the middle of the reservoir now lies, to form the single Volta River. The present Volta River flows from the outlets of the dam's powerhouse and spillways to the Atlantic Ocean in southern Ghana. The main islands within the lake are Dodi, Dwarf, and Kporve. Digya National Park lies on part of the lake's western shore. The lake is formed by the Akosombo Dam, which was originally conceived by the geologist Albert Ernest Kitson in 1915, but whose construction only began in 1961