Lake Sakakawea, upper left, is a reservoir in the Missouri River basin in central North Dakota. It is the third largest man-made lake in the United States, after Lake Mead and Lake Powell. Here it is covered with snow and ice, thus appearing white.
It is located about 80 km (50 mi) from Bismarck, North Dakota; the distance by the river is about 120 km (75 mi). The lake averages between 2 and 3 miles (3–5 km) in width and is 14 miles (21 km) wide at its widest point (Van Hook arm). Lake Sakakawea marks the maximum southwest extent of glaciation during the ice age.
The reservoir was created with the completion of Garrison Dam in 1956, the second (and largest) of six main-stem dams on the Missouri River built and managed by the U.S. Army Corps of Engineers for flood control, hydroelectric power, navigation and irrigation.
The creation of the lake displaced members of the Fort Berthold Indian Reservation from the cities of Van Hook and (Old) Sanish, forcing the creation of New Town. A third reservation town, Elbowoods was also lost to the lake.