Mackenzie River from the Peace-Athabasca system are significantly slowed by the delta area at the western end of Lake Athabasca causing the lake to rise, and the excess water can only flow out after the rivers have receded. The same phenomenon occurs at Great Slave Lake, which naturally regulates the flow from the Slave River into the Mackenzie. There are river gages at several upstream points along the Mackenzie River. The average flow rate at the outlet of Great Slave Lake is . At Fort Simpson, below the Liard River, it is . At Norman Wells it is , and at the
Boats of the Mackenzie River watershed Boats of the Mackenzie River watershed The Mackenzie River in Canada's Northwest Territories is a historic waterway, used for centuries by the original Dene as a travel and hunting corridor. It is part of a larger watershed that includes the Slave, Athabasca, and Peace rivers extending from northern Alberta. In the 1780s, Peter Pond, a trader with the North West Company discovered this watershed and began viable trade with the Athapascan-speaking Dene of these rivers. The Mackenzie River itself, the great waterway extending to the Arctic Ocean, was first put on European maps by Alexander Mackenzie in 1789, the Scottish