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
Waitaki River Waitaki River The Waitaki River is a large braided river that drains the Mackenzie Basin and runs some south-east to enter the Pacific Ocean between Timaru and Oamaru on the east coast of the South Island of New Zealand. It starts at the confluence of the Ohau River and the Tekapo River, now in the head of the artificial Lake Benmore, these rivers being fed by three large glacial lakes, Pukaki, Tekapo, and Ohau. The Waitaki flows through Lake Benmore, Lake Aviemore and Lake Waitaki, these lakes being contained by hydroelectric dams, Benmore Dam, Aviemore Dam and Waitaki Dam. The