Grand Coulee Dam the plateau. MWAK eventually sold Mason City to Reclamation in 1937 before its contract was completed. In 1956, Reclamation combined both Mason City and Engineer's Town to form the city of Coulee Dam. It was incorporated as a city in . With the onset of World War II, power generation was given priority over irrigation. In 1943, Congress authorized the Columbia Basin Project and the Bureau of Reclamation began construction of irrigation facilities in 1948. Directly to the west and above the Grand Coulee Dam, the North Dam was constructed. This dam, along with the Dry Falls Dam to the
Grand Coulee, Washington Grand Coulee, Washington Grand Coulee is a city in Grant County, Washington, United States. The population was 988 at the 2010 census. Grand Coulee was officially incorporated on November 6, 1935. It is located above the Grand Coulee Dam and next to North Dam. Grand Coulee is located at (47.939706, -119.001597). According to the United States Census Bureau, the city has a total area of , of which, is land and is water. As of the census of 2010, there were 988 people, 474 households, and 246 families residing in the city. The population density was . There were 554