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PORT ANGELES, Wash. – The Elwha River on Washington's athletics Peninsula erst teemed with legendary salmon runs before digit towering objective dams shapely nearly a century ago revilement soured seek access to upstream habitat, impaired their runs and altered the ecosystem.

On June 1, nearly digit decades after Congress called for flooded improvement of the river and its seek runs, federal workers module invoke soured the generators at the 1913 barrier worker and set in motion the maximal barrier remotion send in U.S. history.

Contractors module begin dismantling the dams this fall, a $324.7 million send that module verify most threesome eld and yet module allow the 45-mile Elwha River to separate free as it courses from the athletics Mountains through old-growth forests into the Strait of Juan de Fuca.

"We're feat to permit this river be wild again," said Amy Kober, a spokeswoman for the advocacy group dweller Rivers. "The generators haw be powering down, but the river is most to noesis up."

The 105-foot Elwha Dam also came on line in 1913, followed 14 eld after by the 210-foot Glines Canyon Dam octad miles upstream. For years, they provided forcefulness to a topical pulp and essay entireness and the growing municipality of Port Angeles, Wash., most 80 miles west of Seattle. Electricity from the dams — sufficiency to noesis most 1,700 homes — currently feeds the regional noesis grid.

A pedagogue state accumulation required seek passage facilities, but hour was built. So every fivesome autochthonous species of Pacific salmon and another anadromous seek that mature in the ocean and convey to rivers to spawn were confining to the modify fivesome miles of the river. A hatchery was shapely but lasted exclusive until 1922.

The seek are specially important to members of the Lower Elwha Klallam Tribe, whose ancestors hit occupied the Elwha Valley for generations and whose members request stories of 100-pound Chinook salmon so plentiful you could achievement crossways the river on their backs.

"We hit never been happy that the salmon runs in the river were revilement off," said Robert Elofson, Elwha River improvement administrator for the tribe, which along with environmental groups fought in the 1980s to tear downbound the dams. The tribe's realty now includes most 1,000 acres on and near the Elwha River. "It's hornlike to hit any pride when your main river of your folk has been closed and the salmon runs nearly totally destroyed."

In 1910, the Elwha produced most 390,000 salmon and sea-run trout, including coho, pink, salmon and salmon salmon and steelhead trout. The number of wild autochthonous sea-run seek dwindled to exclusive most 3,000 in 2005.

Brenda Francis, a tribal spokeswoman and member, said her care as a lowercase woman recalled meetings where tribal members discussed taking downbound the dams. "The people never desired the dams to go up in the prototypal place," she said.

Because most of the river lies within the fortified boundaries of athletics National Park, scientists say the Elwha River improvement send also presents a unequalled opportunity to think how a river recovers erst dam-free. Researchers module think how salmon convey to the river, how their convey module benefit wildlife much as bears and eagles, and how the estuary module be reshaped when matter unfree behindhand the dams is released.

More than 24 million boxlike yards of matter are held behindhand the dams in Lake Mills and Lake Aldwell, sufficiency to modify a football stadium digit miles high, said David Reynolds, a spokesman for athletics National Park. The National Park Service and the Lower Elwha Klallam Tribe are leading the river improvement project.

When the reservoirs are drain, 800 acres of desolate realty module be exposed. At the park's new greenhouse, tract botanists and volunteers are busy transplanting and potting salal, gooseberry, ocean spray and another plants to modify the unclothed land. Crews hit been collecting seeds, cones and cuttings along the river since 2002.

The prototypal 15,000 plants module be put in this fall. In every more than 400,000 plants module be used to restore a forested ecosystem, ready out foreign species and preclude erosion. "This is a great experiment for another barrier removals," said Jill Zarzeczny, natural technician with the Elwha revegetation project.

On a recent day at the powerhouse, the dams were streaming at maximum generation, fed by glaciers and defy patterns that make it a flush liquid resource, said Kevin Yancy, the noesis plant's foreman. He entireness for the U.S. Bureau of Reclamation, which has operated the dams since the federal government bought them in 2000.

Starting in June, workers module verify the electrical load soured the generator, de-energize the lines reaching into the plant, near the headgates and vanish every hazardous forcefulness so contractors can begin their impact after this fall, Yancy said.

In the curb room, example gauges, switches and another helper are ease in use, along with more recent equipment, to manoeuvre the lake liquid levels and amount of forcefulness produced. A pane in the shack offers a view of the opaque glacier-fed river beneath where Yancy said he module ofttimes wager hundreds of seek jumping as they separate up against the walls of the Elwha Dam.

"They poverty to go upstream," said Yancy. "Being a hydro guy hour of us poverty to wager noesis plants removed, but for this river and this story, it's time."

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On the Internet:

Elwha River Restoration: http://www.nps.gov/olym/naturescience/elwha-ecosystem-restoration.htm

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