The U.S. Army Corps of Engineers is the largest operator of hydroelectric power plants in the U.S., and one of the largest in the world. The 75 Corps plants have a total installed capacity of 20,474 megawatts and produce nearly 100 billion kilowatt-hours a year. 

Nearly a third of the nation's total hydropower output, it's enough energy to serve about ten million households, or roughly ten cities the size of Seattle.

image of hydropower generators

Corps hydropower plants play a key role in the economy by offering an affordable power source, which helps keep overall energy prices down. Because they don't use fossil fuels Corps hydropower plants also are better for the environment than other sources of electrical power. Without hydropower, the U.S. would have to burn much more coal, oil, and natural gas every year.

The increasing availability of hydropower also helps reduce America's dependence on other nations for fuel. The Corps collaborates on its hydropower efforts with the Department of Energy and a variety of other federal, regional and state agencies and private companies. The Corps is in the process of upgrading many of its facilities to increase efficiency and reliability.

Portland District provides a significant amount of this hydropower energy, as shown by the project-specific modules on this page, which are organized alphabetically by region (Jess Dam / Lost Creek in the Rogue River Basin, the Columbia River and the Willamette River Basin).

Mid-Columbia River hydropower

Bonneville Lock & Dam 

1st powerhouse length 1027 ft 313 m
Generators/total output ten 660 mw
2nd powerhouse length 986 ft 300.5 m
Generators/total output eight 558 mw

The Dalles Lock & Dam

Powerhouse length 2089 ft 638 m
Generators/total output 22 2100 mw

John Day Lock & Dam

Powerhouse length 1975 ft 602 m
Generators/total output 16 2160 mw


Rogue River Basin hydropower

Jess Dam & Lost Creek Reservoir
Generators/total output two 49.2 mw

Willamette River Basin hydropower

Big Cliff Dam
Generators / total output one 18 mw


Cougar Dam

Generators / total output two 25 mw


Detroit Dam

Generators / total output two 100 mw


Dexter Dam

Generators / total output one 15 mw


Foster Dam

Generators / total output two 20 mw


Green Peter Dam

Generators / total output two 80 mw


Hills Creek Dam

Generators / total output two 30 mw


Lookout Point Dam

Generators / total output three 120 mw

Types of power used in the U.S.

 pie chart showing U.S. power sources

This shows the sources of power-generating capacity in the U.S. Fossil fuels (primarily coal-fired steam) provide the greatest percentage of our energy (62%), followed by nuclear power (14%), hydropower (13%) and gas turbine power (5%). "Others" refers to wind, solar and geothermal power, which together total 5%.

U.S. hydropower sources

 pie chart showing U.S. hydropower sources

We have 75 power projects Corps-wide, which have a combined total 375 hydropower-generating units. This pie chart indicates the sources of hydropower in the U.S.

Corps output by division/region

Chart showing Corps hydropower production: 63% in the Pacific Northwest, 13% from the Missouri River, 11% in the South Atlantic, 8% in the Southwestern, 4% in the Great Lakes and Ohio River, and 1% in the Mississippi River.The Pacific Northwest produces 63 percent of the United States' hydropower.

More about hydropower

Hydropower has these advantages over alternative fuels:

  • Renewable The earth provides a continual supply of water from rainfall and snowmelt.
  • Efficient Hydropower converts about 90 percent of falling water's energy into electricity.
  • Clean Hydropower plants don't emit waste heat and gases.
  • Reliable Hydropower machinery is relatively simple, making it reliable and durable.
  • Flexible Units can start quickly and adjust rapidly to changes in electricity demand.

The U.S. Army Corps of Engineers has 375 main generating units, plus a number of "house units" that only provide power to run the internal systems of our powerhouses (these are called "Station service Units"). Our smallest units are 1 megawatt or less, but most of our units are much larger. Our largest unit can produce 220 megawatts.

Our powerhouses range from having a single small generating unit,up to having to 27 huge units (the powerhouse at that plant is nearly a half-mile long!). All of our units combined have the capacity to generate 21,000 megawatts--making the Corps of Engineers the largest producer of hydroelectric power in the U.S.

With that amount of production, the sale of hydroelectric power generated from Corps-operated units returns a significant amount of revenue to the U.S. Treasury each year.

How hydropower is generated