Mackenzie River east into the Churchill River. The eastern portion of the Mackenzie basin is dominated by vast reaches of lake-studded boreal forest and includes many of the largest lakes in North America. By both volume and surface area, Great Bear Lake is the biggest in the watershed and third largest on the continent, with a surface area of and a volume of . Great Slave Lake is slightly smaller, with an area of and containing of water, although it is significantly deeper than Great Bear. The third major lake, Athabasca, is less than a third that size with an area of
Mackenzie River (electoral district) meridian in the system of Dominion Land surveys, and on the north by the continental shore of the Arctic Ocean. Mackenzie River (electoral district) Mackenzie River was a federal electoral district in Northwest Territories, Canada, that was represented in the House of Commons of Canada from 1953 to 1963. This riding was created in 1952 when Yukon—Mackenzie River riding was split into two. The parts within the Northwest Territories became Mackenzie River riding. It was abolished in 1962 when it was merged into Northwest Territories riding. It consisted the Provisional District of Mackenzie bounded on the west by the Yukon