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
Clearwater River (Saskatchewan) at Fort McMurray. The section of the river in Fort McMurray is affectionately referred to as The Chant. From Broach Lake at an elevation of above sea level, the Clearwater drops about to the confluence at Fort McMurray. Its waters eventually reach the Arctic Ocean via the Athabasca and Mackenzie Rivers. Tributaries of the Clearwater River include Descharme River and McLean River in Saskatchewan and the Christina River in Alberta. In its upper reaches, the Clearwater River flows over the Precambrian rocks of the Canadian Shield. That section of the river is rough, characterized by rapids, small waterfalls, and a