Grand Coulee Dam
Grand Coulee Dam is a concrete gravity dam on the Columbia River in the U.S. state of Washington, built to produce hydroelectric power and provide irrigation water. Constructed between 1933 and 1942, Grand Coulee originally had two powerhouses. The third powerhouse, completed in 1974 to increase energy production, makes Grand Coulee the largest power station in the United States by nameplate capacity at 6,809 MW.
The proposal to build the dam was the focus of a bitter debate during the 1920s between two groups. One group wanted to irrigate the ancient Grand Coulee with a gravity canal while the other pursued a high dam and pumping scheme. The dam supporters won in 1933, but, although they fully intended otherwise, the initial proposal by the Bureau of Reclamation was for a "low dam" tall which would generate electricity without supporting irrigation. That year, the U.S. Bureau of Reclamation and a consortium of three companies called MWAK began construction on a high dam, although they had received approval for a low dam. After visiting the construction site in August 1934, President Franklin Delano Roosevelt endorsed the "high dam" design, which at high would provide enough electricity to pump water into the Columbia basin for irrigation. Congress approved the high dam in 1935, and it was completed in 1942. The first waters overtopped Grand Coulee's spillway on of that year.
Power from the dam fueled the growing industries of the Northwest United States during World War II. Between 1967 and 1974, the third powerplant was constructed. The decision to construct the additional facility was influenced by growing energy demand, regulated river flows stipulated in the Columbia River Treaty with Canada, and competition with the Soviet Union. Through a series of upgrades and the installation of pump-generators, the dam now supplies four power stations with an installed capacity of 6,809 MW. As the centerpiece of the Columbia Basin Project, the dam's reservoir supplies water for the irrigation of.
The reservoir is called Franklin Delano Roosevelt Lake, named after the president who endorsed the dam's construction. Creation of the reservoir forced the relocation of over 3,000 people, including Native Americans whose lands were flooded. The dam was constructed without fish passage. The next one downstream, Chief Joseph Dam, which was built decades later, also does not have fish passage. This means no salmon reach the Grand Coulee Dam or the Colville Indian Reservation.
Background
The Grand Coulee is an ancient river bed on the Columbia Plateau created during the Pliocene Epoch by retreating glaciers and floods. Originally, geologists believed a glacier that diverted the Columbia River formed the Grand Coulee, but it was revealed in the mid-late 20th century that massive floods from Lake Missoula carved most of the gorge. The earliest known proposal to irrigate the Grand Coulee with the Columbia River dates to 1892, when the Coulee City News and The Spokesman Review reported on a scheme by a man named Laughlin McLean to construct a dam across the Columbia River, high enough that water would back up into the Grand Coulee. A dam that size would have its reservoir encroach into Canada, which would violate treaties. Soon after the Bureau of Reclamation was founded, it investigated a scheme for pumping water from the Columbia River to irrigate parts of central Washington. An attempt to raise funds for irrigation failed in 1914, as Washington voters rejected a bond measure.In 1917, William M. Clapp, a lawyer from Ephrata, Washington, proposed the Columbia be dammed immediately below the Grand Coulee. He suggested a concrete dam could flood the plateau, just as nature blocked it with ice centuries ago. Clapp was joined by James O'Sullivan, another lawyer, and by Rufus Woods, publisher of The Wenatchee World newspaper in the nearby agricultural centre of Wenatchee. Together, they became known as the "Dam College". Woods began promoting the Grand Coulee Dam in his newspaper, often with articles written by O'Sullivan.
The dam idea gained popularity with the public in 1918. Backers of reclamation in Central Washington split into two camps. The "pumpers" favored a dam with pumps to elevate water from the river into the Grand Coulee from which canals and pipes could irrigate farmland. The "ditchers" favored diverting water from northeast Washington's Pend Oreille River via a gravity canal to irrigate farmland in Central and Eastern Washington. Many locals such as Woods, O'Sullivan and Clapp were pumpers, while many influential businessmen in Spokane associated with the Washington Water and Power Company were staunch ditchers. The pumpers argued that hydroelectricity from the dam could cover costs and claimed the ditchers sought to maintain a monopoly on electric power.
The ditchers took several steps to ensure support for their proposals. In 1921, WWPC secured a preliminary permit to build a dam at Kettle Falls, about upstream from the Grand Coulee. If built, the Kettle Falls Dam would have lain in the path of the Grand Coulee Dam's reservoir, essentially blocking its construction. WWPC planted rumors in the newspapers, stating exploratory drilling at the Grand Coulee site found no granite on which a dam's foundations could rest, only clay and fragmented rock. This was later disproved with Reclamation-ordered drilling. Ditchers hired General George W. Goethals, engineer of the Panama Canal, to prepare a report. Goethals visited the state and produced a report backing the ditchers. The Bureau of Reclamation was unimpressed by Goethals' report, believing it filled with errors.
In, President Warren G. Harding visited Washington state and expressed support for irrigation work there, but died a month later. His successor, Calvin Coolidge, had little interest in irrigation projects. The Bureau of Reclamation, desirous of a major project that would bolster its reputation, was focusing on the Boulder Canyon Project that resulted in the Hoover Dam. Reclamation was authorized to conduct a study in 1923, but the project's cost made federal officials reluctant. The Washington state proposals received little support from those further east, who feared the irrigation would result in more crops, depressing prices. With President Coolidge opposed to the project, bills to appropriate money for surveys of the Grand Coulee site failed.
In 1925, Congress authorized a U.S. Army Corps of Engineers study of the Columbia River. This study was included in the Rivers and Harbors Act of, which provided for studies on the navigation, power, flood control and irrigation potential of rivers. In, the Army Corps responded with the first of the "308 Reports" named after the 1925 House Document No. 308. With the help of Washington's Senators, Wesley Jones and Clarence Dill, Congress ordered $600,000 in further studies to be carried out by the Army Corps and Federal Power Commission on the Columbia River Basin and Snake Rivers. U.S. Army Major John Butler was responsible for the upper Columbia River and Snake River and in 1932, his 1,000-page report was submitted to Congress. It recommended the Grand Coulee Dam and nine others on the river, including some in Canada. The report stated electricity sales from the Grand Coulee Dam could pay for construction costs. Reclamation—whose interest in the dam was revitalized by the report—endorsed it.
Although there was support for the Grand Coulee Dam, others argued there was little need for more electricity in the Northwest and crops were in surplus. The Army Corps did not believe construction should be a federal project and saw low demand for electricity. Reclamation argued energy demand would rise by the time the dam was complete. The head of Reclamation, Elwood Mead, stated he wanted the dam built no matter the cost. President Franklin D. Roosevelt, who took office in March 1933, supported the dam because of its irrigation potential and the power it would provide, but he was uneasy with its price tag. For this reason, he supported a "low dam" instead of the "high dam". He provided in federal funding, while Washington State provided $377,000. In 1933, Washington governor Clarence Martin set up the Columbia Basin Commission to oversee the dam project, and Reclamation was selected to oversee construction.
Construction
Low dam
On July 16, 1933, a crowd of 3,000 witnessed the driving of the first stake at the low dam site, marking the start of excavation. Core drilling began in September, while the Bureau of Reclamation accelerated its studies and designs for the dam. The structure was intended to control floods and provide irrigation and hydroelectric power, albeit at a reduced capacity. However, it would not raise the reservoir high enough to irrigate the plateau surrounding the Grand Coulee. The design allowed for the possibility of future height increases and upgrades.Before and during construction, workers and engineers experienced problems. Contracts for companies to construct the various parts of the dam were difficult to award as few companies were sizable enough to fill them. This forced companies to consolidate. Native American graves had to be relocated and temporary fish ladders had to be constructed. During construction additional problems included landslides and the need to protect newly poured concrete from freezing. Construction on the downstream Grand Coulee Bridge began in and more considerable earth-moving began in August. Excavation for the dam's foundation required the removal of 22 million cubic yards of dirt and stone.
To reduce the amount of trucking required in the excavation, a conveyor belt nearly long was built. To further secure the foundation, workers drilled holes into the granite and filled any fissures with grout, creating a grout curtain. At times, excavated areas collapsed from overburden. In order to secure these areas from further movement and continue excavation, diameter pipes were inserted into the mass and chilled with cold liquid from a refrigeration plant. This froze the earth and secured it so construction could continue.
Final contract bidding for the dam began, 1934, in Spokane, and four bids were submitted. One bid was from a lawyer with no financial backing; another was from actress Mae West which consisted of nothing more than a poem and promise to divert the river. Of the two serious bids, the lowest bid was from a consortium of three companies: Silas Mason Co. from Louisville, Kentucky; Walsh Construction Co. of Davenport, Iowa and New York; and Atkinson-Kier Company of San Francisco and San Diego. The consortium was known as MWAK, and their bid was $29,339,301, almost 15% lower than the option submitted by the next bidder, Six Companies, Inc., which was building Hoover Dam at the time.