What Is It?

Spanning the Columbia River in Eastern Washington, Grand Coulee Dam is America’s largest producer of hydroelectricity.


Grand Coulee Dam is 550 feet tall, rising about 350 feet above the water. It is 5,223 feet wide—57 feet short of a mile. Construction began in July 1933 through the Public Works Administration, which helped carry America out of the Depression through heavy investment in publicly-beneficial infrastructure. The dam entered service in 1942.

A lot of concrete

When built, Grand Coulee Dam was the largest concrete structure in the world. The dam contains nearly 12 million cubic yards of concrete—enough to build a highway from Seattle to Miami.

Prime Generator

Grand Coulee Dam generates more than 21 million megawatt-hours of electricity annually. The dam has four power plants. While closed to visitors during the pandemic, tours of one plant—the John W. Keys Pump-Generator— give an inside look at hydroelectricity generation.

Shaping the Land

Coulee refers to a canyon without a river that carved it. Long before Grand Coulee Dam was built, the region had large ice dams. Water bursting through the ice dams shaped the area’s geology. While visiting Grand Coulee Dam, be sure to visit the surrounding scablands and see the cliffs and dry waterfalls.

Plan Your Visit

Check the U.S. Bureau of Reclamation website for information on when the visitors center will reopen.To start planning your trip, call 509-633-9507 or visit usbr.gov/pn/grandcoulee.