When Grand Coulee Dam was being built during the depths of the Great Depression, everything about it--generators, powerhouses, pumps--was the biggest in the world. Grand Coulee was more than a dam; it was a proclamation: America could still do great things. The mile-long behemoth was the largest hydroelectric power-producing facility in the world when it was completed in March 1941--just in time to power the nation's defense plants and the atomic reactors for the Manhattan Project.
