Construction of Grand Coulee Dam: Taming the Columbia River


It took time to get funding to build Grand Coulee Dam. But once federal money was reserved for the project, construction got under way. Even so, it still took 7 years.

It took 14 years from first conception to actual construction to build Grand Coulee Dam across the Columbia River in central Washington State. Power struggles, financing, and technical studies were the main reasons for the delay. But once these obstacles were overcome, construction began in earnest in 1933. The U.S. Bureau of Reclamation (USBR) managed the project, which it awarded to a number of private contractors.

The core drilling contract was awarded to Lynch Bros. of Seattle, and test pit work was awarded to Rumsey and Company of Seattle. They began work on September 9, 1933. On November 30, the government awarded the excavation contract to David H. Ryan Co for $534,000. Ryan subcontracted the west side excavation to Goodfellow Bros. of Wenatchee. Roland Construction Company of Seattle worked on the east side. Western Construction Co. began construction of a bridge across the river near the dam site in May 1934.

On June 18, the major dam construction contract was awarded to the MWAK company. MWAK was composed of Silas Mason Co. of New York, Walsh Construction Co. of Davenport, Iowa, and Atkinson-Kier Company of San Francisco. Silas Mason was the chairman of MWAK.

Construction began August 15, 1934 with more earth moving. On January 1, 1935, work began on a cofferdam on the west side of the river. About 1,200 workers completed it on March 23, 1935. In September, work began on a cofferdam on the east side. The first concrete was poured on December 6, 1935. The pump station and powerhouse foundations were finished first. The Columbia River Bridge opened on January 24, 1936.

At Grand Coulee Dam, preference was given to hiring people in Grant, Lincoln, Douglas, and Okanogan Counties of Washington State. Women were allowed to work at dorms and the cookhouse, but not on the rest of the dam site. The payroll was about $120,000 per week, the largest in the state. The average wage was 80 cents an hour, and they worked 36 hours every 7 days.

MWAK’s portion of building the foundation was completed in early 1938. Consolidated Builders Inc. took over the next phase of dam construction. Consolidated Builders Inc., consisted of MWAK, Kaiser Construction Co. of Seattle; Morrison-Knudsen Co. of Boise; Utah Construction Co. of Ogden, Utah; J. F. Shea Company, Inc. of San Francisco; Pacific Bridge Co. of San Francisco; McDonald and Kahn Co. of San Francisco, and General Construction Co. of Seattle. Henry Kaiser was president. They started work in March 1938.

They built a new concrete mixing plant and a new railroad bridge. Bethlehem Steel built a high trestle that allowed access by cranes to all parts of the structure below. Western Pipe and Steel Co. of San Francisco built the penstocks and inlet pipes. Consolidated started pouring concrete in the summer 1938. By April, there were 5,500 employed. The west powerhouse was ready in December 1939. Turbines were purchased from Newport News Shipbuilding and Dry Dock Co. in Virginia. Westinghouse supplied three 108,000 kw generators for the powerhouse and two smaller 12,500 kw generators to operate dam equipment.

During 1940-41, 1,000 men installed eleven gates 115 feet long and 28 feet high across the spillway. The first small unit started on January 21, 1941 and the second on February 15, 1941. The power was routed to Mason City and Coulee Dam on May 22, 1941. On September 12, 1941, the Nespelem Rural Electric Association became the first customer to buy power from the dam. The USBR took over operation on January 1, 1943.


  1. “Grand Coulee: Harnessing a Dream,” Paul C. Pitzer, Washington State University Press, Pullman, Washington, 1994.