Grand Coulee Dam in central Washington State under a colorful sunset. The dam is the largest capacity power station in the U.S. The nearby Franklin Delano Roosevelt Reservoir provides water for the irrigation of 670,000 acres of farmland in the Columbia Basin. 3,000 people were forced to relocate before construction and numerous First Nation ancestral land sites were flooded. The monumental project was one of a variety of FDR era New Deal projects.