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
Wollaston Lake Wollaston Lake Wollaston Lake is a lake in northeastern Saskatchewan, Canada. It is northeast of Prince Albert. With a surface area of (excluding islands; if islands are included), it is the largest bifurcation lake in the world – that is, a lake that drains naturally in two directions. About 10% of the lake's water drains into the Fond du Lac River, which flows out of the lake to the northwest, where it drains into Lake Athabasca, which ultimately drains into the Arctic Ocean via the Mackenzie River system. The rest of the water drains into the Cochrane River, which flows