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Definition: Grand Coulee Dam from Dictionary of Energy

Hydropower. a dam built in 1942 in Washington State, U.S., to harness the power of the Columbia River. It was the largest hydroelectric dam in the world at that time (in fact the largest concrete structure of any kind), and still remains the largest dam in North America.


Summary Article: Grand Coulee Dam
from Encyclopedia of Politics of the American West

Grand Coulee Dam, the cornerstone of the Columbia Basin Project, was constructed by the Bureau of Reclamation during the period from 1933 to 1941. Located on the Columbia River in eastern Washington, the dam is 550 feet tall and approximately 5,220 feet long. Its reservoir, Lake Roosevelt, was named for Franklin Delano Roosevelt, whose administration approved the construction of the dam during his first presidential term. The dam was a major engineering feat, as it was the largest such structure in the United States at the time.

The dam's proponents, such as Rufus Wood, envisioned that its primary purpose would be as a source of irrigation to transform largely barren land into property suitable for agricultural purposes. They also promoted the project as a way to improve navigation on the river and create hydroelectric power. When Roosevelt assumed the presidency, he saw the dam project as a way to employ thousands of people during the Great Depression while also supporting the growth of the region's economy.

The dam became a reality with the creation in 1933 of the Public Works Administration. Construction commenced the same year, ultimately employing more than twelve thousand workers. They completed construction of the dam in late 1941, soon after the bombing of Pearl Harbor, Hawai'i, by Japan. With the country on a war footing, the generation of hydroelectric power to support the war effort took priority over irrigation improvements. The electricity created at the dam site was distributed throughout the region by the Bonneville Power Administration, and among the users were the nuclear research facilities located in Hanford, Washington. Not until 1944 did the Bureau of Reclamation once again begin to make irrigation improvements a priority. Despite being the first reason for the existence of the dam, irrigation did not begin transforming the region until May 1952, when waters from Lake Roosevelt poured into the adjacent Banks Lake for distribution via a newly created canal system that ranged throughout the Inland Empire portion of Washington State.

Not taken into consideration by the promoters, designers, and builders of the dam were the needs of the Columbia River's anadromous fish populations. The dam prevented the salmon and steelhead from reaching more than a thousand miles of spawning grounds, thus decimating the populations of those fish species. This was extremely devastating to the many Native American groups in the vicinity of the Columbia River and its tributaries. Salmon and related species had been integral to their respective cultures and economies for millennia, and suddenly their access to the fish was essentially gone. Subsequent efforts to restore the river's anadromous fish populations have proven largely inadequate.

Grand Coulee Dam's capacity to create electricity has been continuously expanded since its construction. Thus, it continues to be one of the largest single generators of electrical power in the United States. Without question, the region's agricultural productivity has greatly expanded due to the waters impounded by the dam in Lake Roosevelt. It is estimated that the dam accounts for more than $1.5 billion in economic benefits to the local area annually, with some of that revenue generated by the booming tourist industry that has developed around the reservoir.

See also Columbia River; Hydroelectric Power; Washington

Further Readings
  • Billington, David P.; Donald C. Jackson. Big Dams of the New Deal Era: A Confluence of Engineering and Politics. University of Oklahoma Press Norman, 2006.
  • Ortolano, Leonard; Katherine Kao Cushing. “Grand Coulee Dam 70 Years Later: What Can We Learn?” International Journal of Water Resources Development 18, no. 3 (2002): 373-390. doi:10.1080/0790062022000006880.
  • Pitzer, Paul C. Grand Coulee: Harnessing a Dream. Washington State University Press Pullman, 1994.
  • White, Richard. The Organic Machine: The Remaking of the Columbia River. Hill and Wang New York, 1995.
  • John R. Burch Jr.
    Copyright © 2013 CQ Press

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