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
Mackenzie River According to the British Columbia Environmental Network, "there is enough agricultural capability in the Peace River Valley to provide vegetables to all of northern Canada". The only functioning oil pipeline in the Mackenzie basin connects Norman Wells with Zama City, Alberta. Norman Wells was the main oil producing area on the Mackenzie River until the 1970s, when new oil fields were discovered further north in the Mackenzie delta and the surrounding coastline. As of 2016, there were an estimated 166 billion barrels of oil reserves in this region. There is a proposal for a Mackenzie Valley Pipeline, which has not