Foster Coulee Cordilleran Glacier moved down the Okanogan River valley and blocked the ancient route of the Columbia River, backing up water to create Glacial Lake Columbia. Initially, floodwater discharged from Glacial Lake Columbia by running up through the head of Grand Coulee and down through Foster Coulee to rejoin the Columbia River. After the floods, meltwater from the glacier reversed course and flowed east through the coulee, forming a hanging valley above the west rim of Grand Coulee and a debris fan on the Grand Coulee floor that can be seen today. As the glacier moved further south, Foster Coulee was
Grand Coulee Dam (song) the recommendation of Alan Lomax, the BPA hired Guthrie to write a set of propaganda songs about the federal projects to gain support for federal regulation of hydroelectricity. Although the intended documentary film was not completed until 1949, Guthrie's songs were recorded in Portland, Oregon in May 1941. The tune for "Grand Coulee Dam" is based on that of the traditional song, "The Wabash Cannonball". Guthrie's recording was reissued on the Folkways album "Bound For Glory" in 1956, and subsequently on numerous compilations of Guthrie's songs. The song was later recorded by British skiffle musician Lonnie Donegan, whose version entered