Boats of the Mackenzie River watershed carrier business in 1947. The last steam-propelled sternwheelers, the "S.S. Distributor" and "S.S. Mackenzie" were retired around the same time. In later years, with the construction of the Mackenzie Highway from Alberta to Great Slave Lake, the importance of the Athabasca-Slave River route dwindled and NTCL operations were based from shipyards in Hay River after 1959. NTCL became the primary water operator in the Mackenzie River watershed with the purchase of Hudson's Bay Company's fleet and equipment in 1958, and the total buyout of Yellowknife Transportation Company in 1965 including its fleet of diesel tug boats. Other small commercial operators
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