The largest dam removal project in U.S. history will get under way this year in Washington’s Olympic National Park with destruction of two dams across the Elwha River.
Removal of the dams will take two and a half to three years, and restoration of the natural habitat will take much longer, up to 25 years for the salmon runs to fully recover and many years longer to repair the tattered ecosystem.
What prompted the damming of the Elwha? Over 100 years ago, Thomas Aldwell saw the 45-mile long Elwha River and its narrow gorges as an economic opportunity. Between 1910 and 1913, Aldwell’s Olympic Power and Development Company constructed the 108-foot-high dam five miles from the river mouth. Despite a Washington state law requiring fish passage facilities, the dam was erected without them.
Thomas Aldwell boasted that the Elwha is “…. no longer a wild stream crashing down to the Strait; the Elwha was peace and power and civilization.”
The Elwha Dam and another, the 210-foot high Glines Canyon Dam (also known as the Upper Elwha Dam, built in 1927) originally provided hydroelectric power for growth as far away as the Bremerton naval shipyard. In later years they provided about half the power for a paper mill. These areas are now receiving power from other sources.
The dams were responsible for the decline of hundreds of thousands of fish–coho, pink, chum, chinook and sockeye salmon, as well as steelhead, char and cutthroat trout. With the fish reduced to almost zero, 137 species of wildlife, from the tiny shrews to eagles, mink, elk and bear, were drastically reduced.
Extensive environmental studies showed that dam removal was the only way to restore native anadromous fish stocks and thus the river’s ecosystem. Several large projects were completed in 2009 and 2010 in preparation for the actual dam removal.
The work will restore the river to its natural free-flowing state, allowing all five species of Pacific salmon and other fish to once again reach spawning and rearing habitat. Reforestation will gradually begin, giving habitat to countless other wildlife. Nutrients that link the sea to terrestrial ecosystems will be restored.
One of the important beneficiaries of the Elwha River’s restoration is the Lower Elwha Klallam Tribe, who have lived along the river since time immemorial. Tribal members will have access to sacred sites now inundated by water, and cultural traditions can be reborn. The National Park Service and the tribe are primary partners on this project.
The cost for dam removal and supporting projects is staggering: approximately $352 million, which includes the purchase of the two dams, the removal of the dams, development of two water treatment plants and other facilities to protect water users, and construction of flood protection facilities, a fish hatchery and a greenhouse to propagate native plants for revegetation. The return, in addition to the restoration of the natural ecosystem, will be an increase in the local economy through tourism, recreation and fishing.
This project creates a living laboratory where people can watch and learn what happens when salmon return, after a century, to a still wild and protected ecosystem. What an exciting project to observe and view first-hand!
You can find more information about the project at nps.gov/olym/naturescience/elwha-ecosystem-restoration.htm
Writer Mary E. Trimble and her photographer husband, Bruce, live in Camano Island, Washington.