Athabasca River is marked by rapids, impeding navigation southwest of Fort McMurray. The Athabasca River travels before draining into the Peace-Athabasca Delta near Lake Athabasca south of Fort Chipewyan. From there, its waters flow north as Rivière des Rochers, then joining the Peace River to form the Slave River that empties into Great Slave Lake and discharges through the Mackenzie River system into the Arctic Ocean. The cumulative drainage area is . Numerous communities are located on the banks of the Athabasca River, including Jasper, Brule, Entrance, Hinton, Whitecourt, Fort Assiniboine, Smith, Athabasca, Fort McMurray, and Fort McKay. An independent study has
Mackenzie River which empty into the Pacific Ocean. Lowland divides in the north separate the Mackenzie basin from the Arctic Ocean watersheds of the Anderson, Horton, Coppermine and Back Rivers. In the east, the Mackenzie borders on the Hudson Bay watersheds of the Thelon and Churchill Rivers, and to the south it is bordered by the Saskatchewan–Nelson River system, which also empties into Hudson Bay. The Mackenzie system is hydrologically connected to the Hudson Bay watershed via Wollaston Lake, which is not only the source of the Fond du Lac tributary of Lake Athabasca, but also of the Cochrane River, which flows