Saskatchewan River, a river of southwestern Canada, formed by the union of the North and South Saskatchewan rivers. From their headwaters, close together in the Rocky Mountains along the British Columbia-Alberta border, these two rivers flow eastward and join near Prince Albert, Saskatchewan. From there the Saskatchewan River continues eastward some 340 miles (547 km) to its outlet at Lake Winnipeg in Manitoba. The distance from the head of the Bow River (principal headstream of the South Saskatchewan) to Lake Winnipeg is 1,205 miles (1,939 km).
The Saskatchewan River drains a large part of Canada's Prairie Provinces. With the Nelson River, which flows out of Lake Winnipeg, it forms one of North America's longest river systems. Once valuable as a fur-trading route, the river now furnishes hydroelectric power and irrigation water.
