Lake Claire (Alberta) contains Baril Lake and Mamawi Lake. The waters are discharged in the Peace River, finding their way to the Arctic Ocean through the Slave River, Great Slave Lake and Mackenzie River. Lake Claire (Alberta) Lake Claire is the largest lake which is entirely in Alberta, Canada. It is located entirely in Wood Buffalo National Park, west of Lake Athabasca. It lies between the mouths of Peace River and Athabasca River, and is part of the Peace-Athabasca Delta system. The lake has a total area of , with island area, and lies at an elevation of . It is the largest
Mackenzie River 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. The Mackenzie drainage basin is bordered by multiple major North American watersheds. Much of the western edge of the Mackenzie basin runs along the Continental Divide. The divide separates the Mackenzie watershed from that of the Yukon River, which flows to the Bering Strait; and the Fraser River and Columbia River systems, both of