hydro turbines
 The foundation of the Northwest hydropower system is the Columbia River and its largest tributary, the Snake River. The Columbia is the largest river in the Pacific Northwest, flowing from the Rocky Mountains in Canada into Washington before emptying into the Pacific Ocean. Its drainage basin is roughly the size of France, extending into seven U.S. states and a Canadian province.

The federal government owns and operates 31 dams in the Northwest. The dams on the Columbia River and its tributaries produce more electricity than any other North American river.

Dams on the Columbia River Basin 

Columbia River Basin Dams

Of the 31 federal dams, the 8 dams on the lower mainstem Columbia and Snake rivers alone provide the region with about 4,300 megawatts of firm (consistently available) energy during periods of normal precipitation—enough to power almost four cities the size of Seattle.

The federal dams on the Columbia and Snake Rivers are operated by the U.S. Army Corps of Engineers and the Bureau of Reclamation. The Bonneville Power Administration (BPA) markets the power they produce to Northwest utilities and throughout the West. BPA also builds and operates the transmission lines that bring this power to market.

How a Dam Works 

nwrpHydro System Structure