Geology of the Pacific Northwest along their course. The larger cataract was that of the upper Grand Coulee, where the river roared over an waterfall. The eroding power of the water plucked pieces of basalt from the precipice, causing the falls to retreat and self-destruct by cutting through to the Columbia River valley near what is now the Grand Coulee Dam. The other major cataract is now known as Dry Falls. It started near Soap Lake in Washington State, where less resistant basalt layers gave way before the great erosive power of this tremendous torrent and waterfalls developed. As in the upper Grand Coulee, the
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