Glines Canyon Dam
Glines Canyon Dam
Location of Glines Canyon Dam in Washington (state) Show map of Washington (state) Glines Canyon Dam (the United States) Show map of the United States
Location	On Elwha River, along Olympic Hot Springs Road, about 11 miles (18 km) southwest of Port Angeles, in Olympic National Park, Clallam County, Washington, USA
Coordinates	48°00′07″N 123°36′00″W / 48.00203°N 123.59991°W / 48.00203; -123.59991
Construction began	1925
Opening date	1927
Demolition date	2014
Built by	Thebo, Starr, & Anderson Inc.
Designed by	P.M. Thebo; W.B. McMillan; W.A. Whitmire; H.R. Stevens; H. Schorer
Dam and spillways
Impounds	Elwha River
Height	210 ft (64 m)
Reservoir
Creates	Lake Mills
Total capacity	40,500 acre⋅ft (50,000,000 m3)
Surface area	415 acres (168 ha)
Power Station
Installed capacity	13.3 MW[1]
Glines Canyon Hydroelectric Power Plant
U.S. National Register of Historic Places
U.S. Historic district
Area	7 acres (2.8 ha)
Architectural style	Classical Revival
MPS	Hydroelectric Power Plants in Washington State, 1890--1938 MPS
NRHP reference No.	88002742[2]
Added to NRHP	December 15, 1988

Glines Canyon Dam, also known as Upper Elwha Dam,^[3] built in 1927, was a 210-foot (64 m) high concrete arch dam built on the Elwha River within Olympic National Park, Clallam County, Washington.

It was located 13 miles (21 km) upstream from the mouth of the Elwha River at the Strait of Juan de Fuca, and about 8 miles upriver from the Elwha Dam. It impounded Lake Mills reservoir. The dam was demolished in 2014 as part of the Elwha River ecosystem restoration project; as of 2015 it is the tallest dam ever to be intentionally breached. The Glines Canyon Dam was the largest dam removal ever.

History

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

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

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.

Gallery

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  Glines Canyon Dam (removed) from above, Oct 2014
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  Glines Canyon Dam (removed) from inside reservoir, Oct 2014