Glines Canyon Dam, also known as Upper Elwha Dam,[3] was a 210-foot (64 m) tall concrete arch dam that impounded Lake Mills reservoir on the Elwha River in Clallam County, Washington. As of 2015, it is the tallest dam ever to be intentionally breached.

Glines Canyon Dam
Glines Canyon Dam
Glines Canyon Dam is located in Washington (state)
Glines Canyon Dam
Location of Glines Canyon Dam in Washington (state)
Glines Canyon Dam is located in the United States
Glines Canyon Dam
Glines Canyon Dam (the United States)
LocationOn Elwha River, along Olympic Hot Springs Road, about 11 miles (18 km) southwest of Port Angeles, in Olympic National Park, Clallam County, Washington, USA
Coordinates48°00′07″N 123°36′00″W / 48.00203°N 123.59991°W / 48.00203; -123.59991
Construction began1925
Opening date1927
Demolition date2014
Built byThebo, Starr, & Anderson Inc.
Designed byP.M. Thebo; W.B. McMillan; W.A. Whitmire; H.R. Stevens; H. Schorer
Dam and spillways
ImpoundsElwha River
Height210 ft (64 m)
Reservoir
CreatesLake Mills
Total capacity40,500 acre⋅ft (50,000,000 m3)
Surface area415 acres (168 ha)
Power Station
Installed capacity13.3 MW[1]
Glines Canyon Hydroelectric Power Plant
Area7 acres (2.8 ha)
Architectural styleClassical Revival
MPSHydroelectric Power Plants in Washington State, 1890--1938 MPS
NRHP reference No.88002742[2]
Added to NRHPDecember 15, 1988

Built in 1927, Glines Canyon Dam was located 13 miles (21 km) upriver from the mouth of the Elwha River at the Strait of Juan de Fuca, and about 8 miles (13 km) upriver from Elwha Dam. Both dams lay within Olympic National Park, established in 1938. The National Park Service demolished Glines Canyon Dam in 2014 as part of the restoration of the Elwha River (Elwha Dam was demolished in 2011–2012). The project was the largest dam removal in history until the restoration of the lower Klamath River in the 2020s.

History

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The dam was built privately to generate electricity for industries and major military installations on the Olympic Peninsula, including lumber and paper mills in Port Angeles.

The Glines Canyon Hydroelectric Power Plant historic district, a 7 acres (2.8 ha) area comprising the dam, the powerhouse, and the water conveying system, was listed on the National Register of Historic Places in 1988.[4]

Effects of dam on river habitat and area ecology

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Lacking passage for migrating salmon, Glines Canyon Dam blocked access by anadromous salmonids[5] to the upper 38 miles (61 km) of mainstem habitat and more than 30 miles (48 km) of tributary habitat. The Elwha River watershed once supported salmon runs of more than 400,000 adult returns on more than 70 miles (110 km) of river habitat. By the early 21st-century, fewer than 4,000 adult salmon returned each year.

Habitat restoration

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Elwha river and dam locations

Numerous groups lobbied Congress to remove the two dams on the river and restore the habitat of the river and its valley. The Elwha River Ecosystem and Fisheries Restoration Act of 1992 authorized the US Federal Government to acquire the Elwha Dam and Glines Canyon Dam hydroelectric power projects for decommissioning and demolition for habitat restoration.

The Elwha Ecosystem Restoration project started in September 2011 as work to demolish the nearby Elwha Dam began downstream. The final piece of the Glines Canyon Dam was removed August 26, 2014.[6] Now that the dam has been removed, the area that was under Lake Mills is being revegetated and its banks secured to prevent erosion and to speed up ecological restoration.

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See also

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References

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  1. ^ "Restoring Rivers: Major upcoming dam removals in the Pacific Northwest" (PDF). www.water.ca.gov. Archived from the original (PDF) on December 21, 2016. Retrieved June 21, 2016.
  2. ^ "National Register Information System". National Register of Historic Places. National Park Service. July 9, 2010.
  3. ^ U.S. Geological Survey Geographic Names Information System: Upper Elwha Dam
  4. ^ "National Register of Historical Places record for Glines Canyon Hydroelectric Power Plant". Archived from the original on August 11, 2022. Retrieved June 23, 2017. and accompanying pictures
  5. ^ Grossman 2002, p. 155
  6. ^ "Olympic park's Elwha River freed after last dam blasted out". August 27, 2014. Archived from the original on August 16, 2022. Retrieved June 29, 2017.

Sources

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