The U.S. Army Corps of Engineers is the single largest owner and operator of hydropower in the U.S., with 24 percent of the nation's hydropower generating capacity!

Most of USACE hydropower production is in the Northwestern Division.

The total plant capacity of USACE dams in the Pacific Northwest is 14,524 MW across 3 districts.

Walla Walla District Hydropower Projects

The Walla Walla District operates and maintains six hydropower facilities:

Project River State Service Rating
Dworshak North Fork Clearwater Idaho 400 MW
Ice Harbor Snake Washington 651 MW
Little Goose Snake Washington 810MW
Lower Granite Snake Washington 810MW
Lower Monumental Snake Washington 810MW
McNary Columbia Oregon/ Washington 980 MW


These facilities provide a clean, reliable, renewable, efficient, flexible power source that helps reduce the region’s carbon emissions footprint.

These facilities are capable of producing 4,400 megawatts of energy, enough to power a city the size of Seattle. Annual production equals about 15 billion kilowatts, which equates to about $895 million. Kaplan Turbines are the main workhorse of the District. They are approximately 90 to 95% efficient and have adjustable blades allowing operators to tilt them in response to changing water conditions. While they are a little more complex than other turbines, they turn at only 87.5 rpm and are designed to have a long service life.

How electricity is generated
Water flowing downstream at dams produces electricity. As the water passes through the dam’s powerhouse, it falls from the upstream level behind the dam to a lower downstream level. This water is moving with tremendous force and is guided down to the turbine. As it strikes the blades of the turbine, the water turns the turbine like a propeller. The turning turbine spins coils of wires inside a large generator mounted above it, converting the mechanical energy of falling water into electrical energy. Transmission lines then carry the electricity to homes and businesses.