Grand Coulee Dam the generators and also travel across the main dam span (otherwise closed to the public) as the formerly used glass elevator is indefinitely out of service. Folk singer Woody Guthrie wrote some of his most famous songs while working in the area in the 1940s. 1941 after a brief stay in Los Angeles, Guthrie and his family moved north to Oregon on the promise of a job. Gunther von Fritsch was directing a documentary about the Bonneville Power Administration's construction of the Grand Coulee Dam on the Columbia River, and needed a narrator. Alan Lomax had recommended Guthrie to narrate
Grand Coulee Dam of electricity. Each generator is supplied with water by an individual penstock. The largest of these feed the Third Powerplant and are in diameter and can supply up to . The dam's power facilities originally had an installed capacity of 1,974 MW but expansions and upgrades have increased generation to 6,809 MW installed, 7,079 MW maximum. Grand Coulee Dam generates 21 TWh of electricity annually. This means the dam generates about 2,397 MW of power on average, which results in a total plant factor efficiency of 35%. In 2014, 20.24 TWh of electricity was generated. Grand Coulee Dam's spillway is