Mackenzie River great depths to bedrock. A characteristic feature of the delta is its numerous pingos, or hills of earth-covered-ice – some 1,400 of them. The Peel River, carrying much of the runoff from the northern Yukon, joins in the delta at a point northeast of Fort McPherson. Below there, the Mackenzie diverges into several large channels with the largest heading north-northeast, emptying into the Beaufort Sea west of Tuktoyaktuk. At , the Mackenzie River drainage basin encompasses nearly 20 percent of Canada. About , or 54 percent of the basin, lies above Great Slave Lake. Permafrost underlies about three-quarters of the
Whitesand River (Lake Nipigon) Whitesand River (Lake Nipigon) The Whitesand River is a river in Thunder Bay District, Ontario, Canada, that flows south into the northwest side of Lake Nipigon. Another river in Thunder Bay District with the same name, Whitesand River (Hewitson River), lies further southeast and flows into Lake Superior via the Hewitson River. The river begins at Selassie Lake at an elevation of . Selassie Lake is adjacent to Haile Lake, which also flows into Lake Nipigon, but via the Pikitigushi River system. The names of the two lakes are a reference to Haile Selassie I of Ethiopia. From Selassie Lake,