47°57′21″N 118°58′54″W / 47.95583°N 118.98167°W
| Grand Coulee Dam | |
|---|---|
  | |
| Country | United States |
| Location | Grant / Okanogan counties, Washington |
| Purpose | Power, regulation, irrigation |
| Status | Operational |
| Construction began | July 16, 1933 |
| Opening date | June 1, 1942 |
| Construction cost | Original dam:
$163 million 1943[1] Third powerplant: $730 million 1973[2] |
| Operator(s) | Bureau of Reclamation |
| Dam and spillways | |
| Type of dam | Concrete gravity |
| Impounds | Columbia River |
| Height | 550 ft (168 m) |
| Length | 5,223 feet (1,592 m) |
| Width (crest) | 30 ft (9 m)[3] |
| Width (base) | 500 ft (152 m) |
| Dam volume | 11,975,520 cu yd (9,155,942 m3) |
| Spillway type | Service, drum gate |
| Spillway capacity | 1,000,000 cu ft/s (28,317 m3/s) |
| Reservoir | |
| Creates | |
| Total capacity | 9,562,000 acre⋅ft (12 km3) |
| Active capacity | 5,185,400 acre⋅ft (6 km3) |
| Catchment area | 74,100 sq mi (191,918 km2) |
| Surface area | 125 sq mi (324 km2) |
| Power Station | |
| Commission date | 1941–1950 (Left/Right) 1975–1980 (Third) 1973–1984 (PS) |
| Type | Conventional, pumped-storage |
| Hydraulic head | 380 ft (116 m) |
| Turbines | 33: 27 × Francis turbines 6 × pump-generators |
| Installed capacity | 6,809 MW[4] 7,079 MW (max) |
| Capacity factor | 36%[5] |
| Annual generation | 20.24 TWh[4] |
| Website http://www.usbr.gov/pn/grandcoulee/ | |
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 ("Nat"), 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.[6]
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" 290 feet (88 m) tall which would generate electricity without supporting irrigation. That year, the U.S. Bureau of Reclamation and a consortium of three companies called MWAK (Mason-Walsh-Atkinson Kier Company) began construction on a high dam, although they had received approval for a low dam.[7] After visiting the construction site in August 1934, President Franklin Delano Roosevelt endorsed the "high dam" design, which at 550 ft (168 m) 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 June 1 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 671,000 acres (2,700 km2).
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 partially 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. The third large dam downstream, Wells Dam, has an intricate system of fish ladders to accommodate yearly salmon spawning and migration.
- ^ Ortolano & Cushing 2000, p. 60
- ^ Ortolano & Cushing 2000, p. 61
- ^ Cite error: The named reference
recdimwas invoked but never defined (see the help page). - ^ a b "Grand Coulee Powerplant". U.S. Bureau of Reclamation. Archived from the original on April 29, 2014. Retrieved March 11, 2015.
- ^ "Dams and Energy Sectors Interdependency Study" (PDF). September 2011. Archived (PDF) from the original on January 28, 2017. Retrieved November 16, 2016.
- ^ "Renewable Energy Sources: A Consumer's Guide". U.S. Department of Energy: Energy Information Administration. Archived from the original on May 26, 2010. Retrieved January 28, 2014.
- ^ Reisner, Marc. (1986). Cadillac desert : the American West and its disappearing water. New York, N.Y., U.S.A.: Viking. ISBN 0-670-19927-3. OCLC 13423435.