Elwha Ecosystem Restoration

The Elwha Ecosystem Restoration Project in the United States is the largest dam removal project in history and the second largest ecosystem restoration project in the history of the National Park Service, after the Restoration of the Everglades.

History of the Elwha River

Historically, the Elwha River was one of the few in the Pacific Northwest to contain all 5 species of Pacific Salmon, as well as, anadromous Steelhead, Coastal cutthroat trout, and bull trout. Prior to the construction of the two dams on the river in the early 20th century, approximately 400,000 adult salmon returned to the river each year to spawn in over 70 miles of pristine river habitat, including the tributaries.

Pink Salmon were historically the most numerous salmon species in the river with over 200,000 adult returns. Coho occupied the largest area of the watershed, going up many of the tributaries, and to nearly the headwaters of the Elwha River.

Salmon were an important food source for the Elwha Klallam people who lived at the mouth of the river. In addition, the carcasses that were left behind by spawning salmon triggered a mass migration of animals to the river each year. Animals such as black bear, coyotes, gray wolves, bald eagles, racoons, and dozens of other animals fed on the carcasses to build up their fat supplies to survive the winter.

The Carcasses also supplied the river with ocean-derived nutrients that are typically unavailable in the cold clear waters from the mountain snowpack. This provides nutrients for bacteria,

The Dams

The primary function of this project is the removal of the 108-ft Elwha Dam and the 210-ft Glines Canyon Dam from the Elwha River on the Olympic Peninsula of Washington state. When the Elwha Dam was built in 1910 by Thomas Aldwell, it blocked passage for these salmon, limiting them to the lower 4.9 miles of river below the dam. Today, less than 4,000 salmon return each year to the river. In 1926, 7 miles up stream, the Glines Canyon Dam was built.

Olympic National Park came into existence 1938 and Glines Canyon Dam and Lake Mills were included in the boundaries of the park in 1940. This created the difficult situation where a national park tasked with preserving natural ecosystems, had a man-made system within its boundaries.

When Thomas Aldwell began construction of the Elwha Dam in 1910, he cut corners in the construction and did not secure the dam to the bedrock. In 1912, as the reservoir began to fill up behind the nearly completed dam, the pressure built up so greatly, that the underside of the dam blew out and a torrent of water went downstream, destroying the bridge below.

Thomas Aldwell got the funding to rebuild the dam. In 1913, it began operation. However, he still did not secure the dam to the bedrock, choosing instead to plug the holes with dirt fill, rocks, and wood. Because of this and other reasons, this dam has never been federally licensed to operate.

In addition, even in 1910, it was recognized that the Elwha River was a special river to Pacific Salmon. At the time, the Washington State Fish Commissioner requested that he include fish passages on the dam, which Thomas Aldwell ignored.

ediment Load

With the Glines Canyon Dam blocking sediment from reaching the Strait of Juan de Fuca for over 80 years, most of it has been accumulating in Lake Mills. Historically, the sediment from the Elwha River would accumulate at the mouth of the river, expanding the delta and forming extensive sandy beaches. In addition, east-flowing currents would transport much of that sediment towards the bluffs of Port Angeles and onto Ediz Hook. However, since the sediment has been accumulating in Lake Mills, wave action and currents have eroded the beaches away until they have become nothing more than rocky or pebbly slopes. The mouth of the river has eroded back several acres over the years, shrinking the size of the Lower Elwha Klallam reservation and eliminating their once abundance clam beds.

Ediz Hook has also eroded away to the point that rip-rap has to be placed on the feature to protect Port Angeles harbor from the erosive effects of the wave action.

The Decision to Remove the Dams

The combined power output of these dams only generates 38% of the electricity necessary to operate the Daishowa America Papermill in Port Angeles, WA. The dams have blocked and nearly eliminated the once enormous runs of salmon in the river and their nutrients into Olympic National Park. The sediment no longer makes it to the sea, resulting in erosional problems on the shore. The Elwha Dam is over 95 years old and still has never been secured to the bedrock, resulting in a potential danger to downstream communities. Because of all of these reasons, in the 1980s people began to discuss the removal of the dams.

A series of political battles occurred locally and in Washington D.C., particularly with Senator Slade Gorton blocking the project, while Senator Brock Adams strong supported the plan. Final approval came with The Elwha River Ecosystem and Fisheries Restoration Act of 1992 authorizing the Secretary of the Interior to acquire and remove two dams on the river and restore the ecosystem and native anadromous fisheries. However, delays in funding the project in the Capitol occurred as Slade Gorton often blocked funding the already authorized measure. Finally, the funding was approved and the project has moved forward.

The federal government purchased the dams from Crown Zellerbach and freed the company from any further liability related to the damage caused by the dams in the past or potentially in the future. Research has been going on for several years into the best ways to remove the dams, while preventing any negative impacts on the water supply for the city of Port Angeles, the communities downstream, and most importantly, the salmon which remain in the river.

The final plans are in place, construction of the two water treatment plants for Port Angeles are underway, and removal of the dams is expected to begin in 2012.

Partnerships, Research, and Education

The partnership includes the National Park Service, the Bureau of Reclamation, and the Lower Elwha Klallam tribe, in addition to, local and state governments and outside public interest groups. As the largest project ever of its kind, huge research opportunities are available and are being pursued by students and professors at Peninsula College and Western Washington University, as well as, professors from many other universities.

The National Park Service and Olympic Park Institute are involved in education projects to inform the public about the history of the river, the dam removal process, ecosystem restoration, and return on the salmon to the river.

References

* [http://www.nps.gov/olym/naturescience/elwha-ecosystem-restoration.htm NPS Elwha Ecosystem Restoration Page]
* [http://www.elwharivereducation.org/ Elwha Restoration Education Website]
* [http://www.nps.gov/olym/naturescience/elwha-restoration-docs.htm Elwha Restoration Documents Online]
* [http://www.yni.org/opi/ Olympic Park Institute]
* [http://www.elwha.org/ Lower Elwha Klallam Tribe]
* [http://www.pc.ctc.edu/coe/elwha.htm Peninsula College Center for Excellence Elwha Program]
* [http://www.pbs.org/americanfieldguide/teachers/salmon/history.pdf Historical Background on Elwha Dam Removal]