List of dams and reservoirs in Washington explained

This is a list of dams and reservoirs in the U.S. state of Washington, and pertinent data. According to the Washington State Department of Ecology, as of 2020 there were 1226 dams in the state. Of 39 counties, King County had the most dams, 125.^[1]

The largest dam in Washington, in terms of structural volume, reservoir capacity and electricity production, is the Grand Coulee Dam on the Columbia River. The tallest dam is Mossyrock Dam on the Cowlitz River, at 606feet. The longest dam is O'Sullivan Dam on Crab Creek, at 19000feet.

List

Dam	County	River	Reservoir	Type	Installed capacity (MW)	Height		Reservoir capacity		Year	Owner	Primary purpose(s)
						ft	m	acre.ft	dam^3
Alder Dam	Pierce/ Thurston	Nisqually River	Alder Lake	Arch		330feet	241950acre feet	1945	Tacoma Power	Hydroelectric
Bonneville Dam†	Skamania	Columbia River	Lake Bonneville	Gravity		197feet	537000acre feet	1937	U.S. Army Corps of Engineers	Hydroelectric, Navigation
Boundary Dam	Pend Oreille	Pend Oreille River	Boundary Lake	Arch-gravity		340feet	95000acre feet	1967	Seattle City Light	Hydroelectric
Box Canyon Dam	Pend Oreille	Pend Oreille River	Box Canyon Reservoir	Gravity		62feet	60000acre feet	1956	Pend Oreille Public Utility District	Hydroelectric
Chief Joseph Dam	Douglas/ Okanogan	Columbia River	Rock Island Pool	Gravity		135feet	516000acre feet	1979	U.S. Army Corps of Engineers	Hydroelectric
Cle Elum Dam	Kittitas	Cle Elum River	Cle Elum Lake	Earthfill		165feet	436900acre feet	1933	U.S. Bureau of Reclamation	Irrigation
Culmback Dam	Snohomish	Sultan River	Spada Lake	Rockfill		262feet	165774acre feet	1965	City of Everett, Snohomish County PUD	Water supply
Cushman Dam No. 1	Mason	North Fork Skokomish River	Lake Cushman	Arch		235feet	453400acre feet	1926	Tacoma Power	Hydroelectric
Cushman Dam No. 2	Mason	North Fork Skokomish River	Lake Kokanee	Arch		175feet	8000acre feet	1930	Tacoma Power	Hydroelectric
Diablo Dam	Whatcom	Skagit River	Diablo Lake	Arch		389feet	88500acre feet	1930	Seattle City Light	Hydroelectric
Dry Falls Dam	Grant	Grand Coulee	Banks Lake	Earthfill		123feet	1275000acre feet	1949	U.S. Bureau of Reclamation	Irrigation
Gorge Dam	Whatcom	Skagit River	Gorge Lake	Gravity		300feet	9700acre feet	1961	Seattle City Light	Hydroelectric
Grand Coulee Dam	Grant/ Okanogan	Columbia River	Franklin Delano Roosevelt Lake	Gravity		550feet	9562000acre feet	1942	U.S. Bureau of Reclamation	Irrigation, Hydroelectric, Flood control
Hiram M. Chittenden Locks and Dam	King	Lake Washington Ship Canal	Lake Washington	Gravity	0	26feet	458000acre feet	1916	U.S. Army Corps of Engineers	Navigation
Howard A. Hanson Dam	King	Green River	Howard A. Hanson Reservoir	Earthfill		235feet	136700acre feet	1961	U.S. Army Corps of Engineers	Flood control, Water supply
John Day Dam†	Klickitat	Columbia River	Lake Umatilla	Gravity		184feet	2530000acre feet	1971	U.S. Army Corps of Engineers	Hydroelectric, Navigation
Ice Harbor Dam	Franklin/ Walla Walla	Snake River	Lake Sacajawea	Gravity		100feet	249000acre feet	1962	U.S. Army Corps of Engineers	Hydroelectric, Navigation
Kachess Dam	Kittitas	Kachess River	Kachess Lake	Earthfill		112feet	239000acre feet	1912	U.S. Bureau of Reclamation	Irrigation
Keechelus Dam	Kittitas	Yakima River	Keechelus Lake	Earthfill		128feet	157900acre feet	1917	U.S. Bureau of Reclamation	Irrigation
LaGrande Dam	Pierce/ Thurston	Nisqually River	LaGrande Reservoir	Gravity		192feet	2700acre feet	1945	Tacoma Power	Hydroelectric
Lake Chelan Dam	Chelan	Chelan River	Lake Chelan	Gravity		40feet	677400acre feet	1927	Chelan County Public Utility District	Hydroelectric
Lake Tapps (Multiple dikes)	Pierce	Off-stream	Lake Tapps	Earthfill				48258acre feet	1911	Cascade Water Alliance	Recreation, Water supply (proposed)
Little Goose Dam	Columbia/ Whitman	Snake River	Lake Bryan	Gravity		96feet	516300acre feet	1970	U.S. Army Corps of Engineers	Hydroelectric, Navigation
Long Lake Dam	Lincoln/ Stevens	Spokane River	Long Lake	Gravity		213feet	105000acre feet	1915	Avista	Hydroelectric
Lower Baker Dam	Skagit	Baker River	Lake Shannon	Arch		285feet	161470acre feet	1925	Puget Sound Energy	Hydroelectric
Lower Granite Dam	Garfield/ Whitman	Snake River	Lower Granite Lake	Gravity		100feet	440200acre feet	1975	U.S. Army Corps of Engineers	Hydroelectric, Navigation
Lower Monumental Dam	Franklin/ Walla Walla	Snake River	Lake Herbert G. West	Gravity		100feet	432000acre feet	1969	U.S. Army Corps of Engineers	Hydroelectric, Navigation
Masonry Dam	King	Cedar River	Chester Morse Lake/ Masonry Pool	Arch-gravity		215feet	93900acre feet	1915	Seattle Public Utilities	Water supply, Hydroelectric
Mayfield Dam	Lewis	Cowlitz River	Lake Mayfield	Arch-gravity		250feet	133764acre feet	1963	Tacoma Power	Hydroelectric
McNary Dam†	Benton	Columbia River	Lake Wallula	Gravity		183feet	1350000acre feet	1954	U.S. Army Corps of Engineers	Hydroelectric, Navigation
Merwin Dam	Clark/ Cowlitz	Lewis River	Lake Merwin	Arch-gravity		313feet	422000acre feet	1931	PacifiCorp	Hydroelectric
Mossyrock Dam	Lewis	Cowlitz River	Riffe Lake	Arch		606feet	1685000acre feet	1968	Tacoma Power	Hydroelectric
Mud Mountain Dam	King	White River	Mud Mountain Lake	Earth/rockfill	0	432feet	106000acre feet	1948	U.S. Army Corps of Engineers	Flood control
Pinto Dam	Grant	Off-stream	Billy Clapp Lake	Earthfill		130feet	21200acre feet	1948	U.S. Bureau of Reclamation	Irrigation
Priest Rapids Dam	Grant/ Yakima	Columbia River	Priest Rapids Lake	Gravity/ Embankment		178feet	237100acre feet	1961	Grant County Public Utility District	Hydroelectric
Rock Island Dam	Chelan/ Douglas	Columbia River	Rock Island Pool	Gravity		135feet	131000acre feet	1933	Chelan County Public Utility District	Hydroelectric
Rocky Reach Dam	Chelan/ Douglas	Columbia River	Lake Entiat	Gravity		130feet	382000acre feet	1969	Chelan County Public Utility District	Hydroelectric
Ross Dam	Whatcom	Skagit River	Ross Lake	Arch		540feet	1435000acre feet	1949	Seattle City Light	Hydroelectric
Skookumchuck Dam	Thurston	Skookumchuck River	Skookumchuck Reservoir	Earthfill		190feet	34800acre feet	1970	TransAlta	Water supply
South Fork Tolt River Dam	King	South Fork Tolt River	South Fork Tolt Reservoir	Earthfill		200feet	57900acre feet	1964	Seattle Public Utilities	Water supply
Swift Dam	Skamania	Lewis River	Swift Reservoir	Earthfill		512feet	755600acre feet	1958	PacifiCorp	Hydroelectric
The Dalles Dam†	Klickitat	Columbia River	Lake Celilo	Gravity		200feet	330000acre feet	1957	U.S. Army Corps of Engineers	Hydroelectric, navigation
Tieton Dam	Yakima	Tieton River	Rimrock Lake	Earthfill		319feet	203600acre feet	1925	U.S. Bureau of Reclamation	Irrigation
Toutle River Sediment Retention Structure	Cowlitz	North Fork Toutle River		Earthfill	0	184feet	160000acre feet	1989	U.S. Army Corps of Engineers	Sediment control
Upper Baker Dam	Whatcom	Baker River	Baker Lake	Arch		312feet	285000acre feet	1959	Puget Sound Energy	Hydroelectric
Wanapum Dam	Grant/ Kittitas	Columbia River	Lake Wanapum	Gravity/ Embankment		185feet	796000acre feet	1963	Grant County Public Utility District	Hydroelectric
Wells Dam	Chelan/ Douglas	Columbia River	Lake Pateros	Gravity		160feet	331200acre feet	1967	Douglas County Public Utility District	Hydroelectric
Wynoochee Dam	Grays Harbor	Wynoochee River	Wynoochee Lake	Gravity		175feet	69405acre feet	1972	City of Aberdeen	Water supply
Yale Dam	Clark/ Cowlitz	Lewis River	Yale Lake	Earthfill		323feet	402000acre feet	1953	PacifiCorp	Hydroelectric

Removed dams

• Condit Dam, on the White Salmon River in Klickitat County
• Elwha Dam and Glines Canyon Dam, on the Elwha River in Clallam County

See also

• List of dams in the Columbia River watershed
• List of hydroelectric power stations in Washington

External links

• Washington State Dams map

Notes and References

1. Web site: Inventory of Dams Report . WA Dept. of Ecology . 20 November 2022 . 11 Sep 2020. (Filesize: ~5MB)