Mackenzie River
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 watershed, reaching up to deep in the Mackenzie Delta. As a whole, the Mackenzie basin receives only meager to moderate rainfall, averaging over the entire basin, though mountain areas experience much higher precipitation, and areas near and north of the Arctic Circle receive much lower precipitation.
List of Hudson Bay rivers
This list of Hudson Bay rivers includes the principal rivers draining into the Hudson, James and Ungava bays of the Arctic Ocean. The total surface area of the Hudson Bay watershed is about , with a mean discharge of about . The drainage basin includes parts of five Canadian provinces (Alberta, Saskatchewan, Manitoba, Ontario and Quebec), territories (Northwest Territories and Nunavut) and four American states (Montana, South Dakota, North Dakota and Minnesota). The two principal waterways are the La Grande Rivière, in Québec, and the Nelson River in Manitoba, each with an average waterflow of over .