Mackenzie River Mackenzie River The Mackenzie River (Slavey language: Deh-Cho , "big river" or Inuvialuktun: Kuukpak , "great river"; ) is the longest river system in Canada, and has the second largest drainage basin of any North American river after the Mississippi River. The Mackenzie River flows through a vast, thinly populated region of forest and tundra entirely within the Canadian Northwest Territories, although its many tributaries reach into four other Canadian provinces and territories. The river's main stem is long, flowing north-northwest from Great Slave Lake into the Arctic Ocean, where it forms a large delta at its mouth. Its extensive
Fond du Lac River (Saskatchewan) Fond du Lac River (Saskatchewan) The Fond du Lac River is one of the upper branches of the Mackenzie River system, draining into the Arctic Ocean, located in northern Saskatchewan, Canada. The river is long, has a watershed of , and its mean discharge is . The river begins at an elevation of at Cunning Bay on Wollaston Lake. It flows north to Hatchet Lake at an elevation of and continues to Waterfound Bay at an elevation of , where the tributary Waterfound River enters from the left. The river continues north to Kosdaw Lake at an elevation of ,