List of dams and reservoirs in Washington

As of 2023, the U.S. state of Washington has 1,242 dams that are able to impound 10 acre-feet or more of water and are regulated by the Washington State Department of Ecology (DOE). These include dams that produce hydroelectricity and create reservoirs for irrigation, drinking water, or recreational uses. According to the DOE, approximately 52 percent of dams in the state are privately-owned, while 31 percent are owned by local governments.[1]

The Chief Joseph Dam, a concrete gravity dam on the Columbia River near Bridgeport, Washington

Approximately 87 percent of dams in Washington are earth fill dams, with the second most-common type being concrete gravity dams (6%). Only 113 dams in the state are taller than 50 feet (15 m). King County has 123 dams—the most of any county in the state.[1] The majority of dams were built between 1960 and 1999.[1] Proposals to remove underused dams and restore fish habitats emerged in the early 21st century with support from the state's Native American tribes; the first major dam removal was the Condit Dam near White Salmon in 2011, which was followed by two dams on the Elwha River near Port Angeles. As of 2024, 39 dams in Washington have been removed.[2]

The largest dam in Washington, in terms of structural volume, reservoir capacity, and electricity production, is the Grand Coulee Dam on the Columbia River. It is the largest power station in the United States with a nameplate capacity of 6,809 megawatts and one of the largest concrete structures in the world.[3] The tallest dam is Mossyrock Dam on the Cowlitz River in Lewis County, at 606 feet (185 m).[4] The longest dam is O'Sullivan Dam on Crab Creek, at 19,000 feet (5,800 m); it is among the longest earth fill dams in the United States.[5]

List

edit
Key
† Located on state border with Oregon
Dams and reservoirs in Washington over 25 feet (7.6 m)[1]
Dam County River Reservoir Type Installed
capacity
(MW)
Height Reservoir
capacity
Year Owner Primary
purpose(s)
ft m acre.ft dam3
Alder Dam Pierce/
Thurston
Nisqually River Alder Lake Arch 50.0 330 100 241,950 298,440 1945 Tacoma Power Hydroelectric
Bonneville Dam Skamania Columbia River Lake Bonneville Gravity 1,242.0 197 60 537,000 662,000 1937 U.S. Army Corps of Engineers Hydroelectric,
Navigation
Boundary Dam Pend Oreille Pend Oreille River Boundary Lake Arch-gravity 1,070.0 340 100 95,000 117,000 1967 Seattle City Light Hydroelectric
Box Canyon Dam Pend Oreille Pend Oreille River Box Canyon Reservoir Gravity 90.0 62 19 60,000 74,000 1956 Pend Oreille Public Utility District Hydroelectric
Chief Joseph Dam Douglas/
Okanogan
Columbia River Rock Island Pool Gravity 2,620.0 135 41 516,000 636,000 1979 U.S. Army Corps of Engineers Hydroelectric
Cle Elum Dam Kittitas Cle Elum River Cle Elum Lake[n 1] Earthfill 165 50 436,900 538,900 1933 U.S. Bureau of Reclamation Irrigation
Culmback Dam Snohomish Sultan River Spada Lake Rockfill 112.0 262 80 165,774 204,479 1965 City of Everett, Snohomish County PUD Water supply
Cushman Dam No. 1 Mason North Fork Skokomish River Lake Cushman Arch 43.2 235 72 453,400 559,300 1926 Tacoma Power Hydroelectric
Cushman Dam No. 2 Mason North Fork Skokomish River Lake Kokanee Arch 81.0 175 53 8,000 9,900 1930 Tacoma Power Hydroelectric
Diablo Dam Whatcom Skagit River Diablo Lake Arch 129.0 389 119 88,500 109,200 1930 Seattle City Light Hydroelectric
Dry Falls Dam[n 2] Grant Grand Coulee Banks Lake Earthfill 123 37 1,275,000 1,573,000 1949 U.S. Bureau of Reclamation Irrigation
Gorge Dam Whatcom Skagit River Gorge Lake Gravity 199.2 300 91 9,700 12,000 1961 Seattle City Light Hydroelectric
Grand Coulee Dam Grant/
Okanogan
Columbia River Franklin Delano Roosevelt Lake Gravity 6,809.0 550 170 9,562,000 11,795,000 1942 U.S. Bureau of Reclamation Irrigation,
Hydroelectric,
Flood control
Hiram M. Chittenden Locks and Dam King Lake Washington Ship Canal Lake Washington[n 3] Gravity 0 26 7.9 458,000 565,000 1916 U.S. Army Corps of Engineers Navigation
Howard A. Hanson Dam King Green River Howard A. Hanson Reservoir Earthfill 235 72 136,700 168,600 1961 U.S. Army Corps of Engineers Flood control,
Water supply
John Day Dam Klickitat Columbia River Lake Umatilla Gravity 2,160.0 184 56 2,530,000 3,120,000 1971 U.S. Army Corps of Engineers Hydroelectric,
Navigation
Ice Harbor Dam Franklin/
Walla Walla
Snake River Lake Sacajawea Gravity 603.0 100 30 249,000 307,000 1962 U.S. Army Corps of Engineers Hydroelectric,
Navigation
Kachess Dam Kittitas Kachess River Kachess Lake[n 4] Earthfill 112 34 239,000 295,000 1912 U.S. Bureau of Reclamation Irrigation
Keechelus Dam Kittitas Yakima River Keechelus Lake[n 5] Earthfill 128 39 157,900 194,800 1917 U.S. Bureau of Reclamation Irrigation
LaGrande Dam Pierce/
Thurston
Nisqually River LaGrande Reservoir Gravity 65.0 192 59 2,700 3,300 1945 Tacoma Power Hydroelectric
Lake Chelan Dam Chelan Chelan River Lake Chelan[n 6] Gravity 59.2 40 12 677,400 835,600 1927 Chelan County Public Utility District Hydroelectric
Lake Tapps (Multiple dikes) Pierce Off-stream Lake Tapps Earthfill 48,258 59,525 1911 Cascade Water Alliance Recreation,
Water supply (proposed)
Little Goose Dam Columbia/
Whitman
Snake River Lake Bryan Gravity 810.0 96 29 516,300 636,800 1970 U.S. Army Corps of Engineers Hydroelectric,
Navigation
Long Lake Dam Lincoln/
Stevens
Spokane River Long Lake Gravity 71.0 213 65 105,000 130,000 1915 Avista Hydroelectric
Lower Baker Dam Skagit Baker River Lake Shannon Arch 79.0 285 87 161,470 199,170 1925 Puget Sound Energy Hydroelectric
Lower Granite Dam Garfield/
Whitman
Snake River Lower Granite Lake Gravity 810.0 100 30 440,200 543,000 1975 U.S. Army Corps of Engineers Hydroelectric,
Navigation
Lower Monumental Dam Franklin/
Walla Walla
Snake River Lake Herbert G. West Gravity 810.0 100 30 432,000 533,000 1969 U.S. Army Corps of Engineers Hydroelectric,
Navigation
Masonry Dam King Cedar River Chester Morse Lake/
Masonry Pool[n 7]
Arch-gravity 30.0 215 66 93,900 115,800 1915 Seattle Public Utilities Water supply,
Hydroelectric
Mayfield Dam Lewis Cowlitz River Lake Mayfield Arch-gravity 162.0 250 76 133,764 164,995 1963 Tacoma Power Hydroelectric
McNary Dam Benton Columbia River Lake Wallula Gravity 986.0 183 56 1,350,000 1,670,000 1954 U.S. Army Corps of Engineers Hydroelectric,
Navigation
Merwin Dam Clark/
Cowlitz
Lewis River Lake Merwin Arch-gravity 136.0 313 95 422,000 521,000 1931 PacifiCorp Hydroelectric
Mossyrock Dam Lewis Cowlitz River Riffe Lake Arch 300.0 606 185 1,685,000 2,078,000 1968 Tacoma Power Hydroelectric
Mud Mountain Dam King White River Mud Mountain Lake Earth/rockfill 0 432 132 106,000 131,000 1948 U.S. Army Corps of Engineers Flood control
Pinto Dam Grant Off-stream Billy Clapp Lake Earthfill 130 40 21,200 26,100 1948 U.S. Bureau of Reclamation Irrigation
Priest Rapids Dam Grant/
Yakima
Columbia River Priest Rapids Lake Gravity/
Embankment
955.6 178 54 237,100 292,500 1961 Grant County Public Utility District Hydroelectric
Rock Island Dam Chelan/
Douglas
Columbia River Rock Island Pool Gravity 623.7 135 41 131,000 162,000 1933 Chelan County Public Utility District Hydroelectric
Rocky Reach Dam Chelan/
Douglas
Columbia River Lake Entiat Gravity 1,299.6 130 40 382,000 471,000 1969 Chelan County Public Utility District Hydroelectric
Ross Dam Whatcom Skagit River Ross Lake Arch 460.0 540 160 1,435,000 1,770,000 1949 Seattle City Light Hydroelectric
Skookumchuck Dam Thurston Skookumchuck River Skookumchuck Reservoir Earthfill 1.0 190 58 34,800 42,900 1970 TransAlta Water supply
South Fork Tolt River Dam King South Fork Tolt River South Fork Tolt Reservoir Earthfill 6.55 200 61 57,900 71,400 1964 Seattle Public Utilities Water supply
Swift Dam Skamania Lewis River Swift Reservoir Earthfill 240.0 512 156 755,600 932,000 1958 PacifiCorp Hydroelectric
The Dalles Dam Klickitat Columbia River Lake Celilo Gravity 1,878.3 200 61 330,000 410,000 1957 U.S. Army Corps of Engineers Hydroelectric,
navigation
Tieton Dam Yakima Tieton River Rimrock Lake Earthfill 15.6 319 97 203,600 251,100 1925 U.S. Bureau of Reclamation Irrigation
Toutle River Sediment Retention Structure Cowlitz North Fork Toutle River [n 8] Earthfill 0 184 56 160,000 200,000 1989 U.S. Army Corps of Engineers Sediment control
Upper Baker Dam Whatcom Baker River Baker Lake Arch 91.0 312 95 285,000 352,000 1959 Puget Sound Energy Hydroelectric
Wanapum Dam Grant/
Kittitas
Columbia River Lake Wanapum Gravity/
Embankment
1,040.0 185 56 796,000 982,000 1963 Grant County Public Utility District Hydroelectric
Wells Dam Chelan/
Douglas
Columbia River Lake Pateros Gravity 851.4 160 49 331,200 408,500 1967 Douglas County Public Utility District Hydroelectric
Wynoochee Dam Grays Harbor Wynoochee River Wynoochee Lake Gravity 10.8 175 53 69,405 85,610 1972 City of Aberdeen Water supply
Yale Dam Clark/
Cowlitz
Lewis River Yale Lake Earthfill 134.0 323 98 402,000 496,000 1953 PacifiCorp Hydroelectric

Removed dams

edit

See also

edit

Notes

edit
  1. ^ Natural lake raised by dam.
  2. ^ Holds Banks Lake along with the smaller North Dam.
  3. ^ Natural lake with its ocean outlet re-routed via the ship canal. The lock and dam structure maintains the lake level.
  4. ^ Natural lake raised by dam.
  5. ^ Natural lake raised by dam.
  6. ^ Natural lake raised by dam.
  7. ^ Chester Morse Lake is a natural lake enlarged by the Chester Morse Dam in 1900. When Masonry Dam was constructed in 1915 it submerged the old dam and created a new body of water, just downstream and connected to Chester Morse Lake, called Masonry Pool.
  8. ^ The Sediment Retention Structure was constructed to trap debris flow sediment after the 1980 eruption of Mount St. Helens. The basin behind the dam is almost entirely filled with silt.

References

edit
  1. ^ a b c d Inventory of Dams Report (PDF) (Report). Washington State Department of Ecology. December 2023. Retrieved November 14, 2024.
  2. ^ a b c Bartoo-Smith, Nika; Breda, Isabella (July 7, 2024). "Why 'deadbeat dam' removals are so difficult in WA, PNW". The Seattle Times. Retrieved November 14, 2024.
  3. ^ "Grand Coulee Dam Statistics and Facts" (PDF). United States Bureau of Reclamation. December 2021. Retrieved November 14, 2024.
  4. ^ Holden Givens, Linda (June 2, 2022). "Mossyrock — Thumbnail History". HistoryLink. Retrieved November 14, 2024.
  5. ^ Tate, Cassandra (August 31, 2005). "Columbia National Wildlife Refuge". HistoryLink. Retrieved November 14, 2024.
edit