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.
Saint John River (Bay of Fundy)
The Saint John River is a long river that flows from Northern Maine into Canada, and runs south along the western side of New Brunswick, emptying into the Atlantic Ocean in the Bay of Fundy. Eastern Canada's longest river, its drainage basin is one of the largest on the east coast at about .