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Grand Coulee Dam
The largest power plant in the United States, on the Columbia River
Grand Coulee Dam generates more electricity than any other power plant in the United States, with a nameplate capacity of about 6,800 megawatts. The concrete wall rises 550 feet (168 m) and runs 5,223 feet (1,592 m) across the Columbia River in central Washington. Work began in 1933 as a New Deal jobs program, and water first poured over the spillway on June 1, 1942, just in time for its power to feed aluminum smelters and the plutonium works at Hanford during World War II. Folk singer Woody Guthrie, hired by the Bonneville Power Administration in 1941, wrote 26 songs in a month celebrating it.
Behind the dam lies Franklin D. Roosevelt Lake, about 125 square miles (324 km²) of reservoir reaching some 151 miles (243 km) up the Columbia toward Canada. Pumps lift water from it into Banks Lake, which feeds the Columbia Basin Project and irrigates about 670,000 acres (2,710 km²) of former sagebrush desert. Established in 1946, Lake Roosevelt National Recreation Area now manages the reservoir's shoreline in partnership with the Colville and Spokane tribes, whose reservations border the reservoir. The lake's level swings widely each year as operators draw it down in spring to make room for snowmelt and flood control downstream.
The dam was built without fish ladders. It cut off more than 1,100 miles (1,770 km) of salmon spawning habitat and flooded Kettle Falls, a fishing place used by Native peoples for thousands of years, along with Colville and Spokane homes and graves. The Colville Tribes won a settlement in the 1990s, and the Spokane Tribe in 2019. The tribes are now leading studies on returning salmon above the dam.