Boats of the Mackenzie River watershed carrier business in 1947. The last steam-propelled sternwheelers, the "S.S. Distributor" and "S.S. Mackenzie" were retired around the same time. In later years, with the construction of the Mackenzie Highway from Alberta to Great Slave Lake, the importance of the Athabasca-Slave River route dwindled and NTCL operations were based from shipyards in Hay River after 1959. NTCL became the primary water operator in the Mackenzie River watershed with the purchase of Hudson's Bay Company's fleet and equipment in 1958, and the total buyout of Yellowknife Transportation Company in 1965 including its fleet of diesel tug boats. Other small commercial operators
Mackenzie River Arctic Red confluence it is . Mackenzie monthly mean discharge at Arctic Red River (m/s)<br> As recently as the last glacial maximum about 30,000 years ago, the majority of northern Canada was buried under the enormous continental Laurentide ice sheet. The tremendous erosive powers of the Laurentide and its predecessors, at maximum extent, completely buried what is now the Mackenzie watershed under thousands of metres of ice and flattened the eastern portions of the watershed. When the ice sheet receded for the last time, it left a long postglacial lake, Lake McConnell, of which Great Bear, Great Slave and Athabasca