Elwha Dam Removal

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The Elwha Dam and Glines Canyon Dam, constructed in the early 1900s in the Elwha Watershed in Washington State, blocked anadromous fish from accessing over 90% of the watershed for over a century. The Elwha River Ecosystem and Restoration Act, passed by Congress after decades of lobbying by the Lower Elwha Klallam Tribe and allies, led to the removal of both dams from 2011 to 2014. This project re-opened more than 70 miles of salmon habitat, marking the first dam removals of such magnitude. Federal Funding was associated with American Recovery and Reinvestment Act of 2009 (ARRA).


Key Partners

Lower Elwha Klallam Tribe National Park Service – Olympic National Park United States Geological Survey University of Washington Washington Department of Fish and Wildlife Trout Unlimited

Fish Populations Before the removal, the dams significantly reduced the river's salmon abundance. Post-removal, anadromous fish such as salmon and Pacific lamprey have returned to previously inaccessible areas, increasing life history diversity and population levels.

Puget Sound Chinook salmon (threatened) Puget Sound steelhead (threatened) Olympic Peninsula bull trout (threatened) Chum salmon Pink salmon Coho salmon Eulachon (threatened) Pacific Lamprey

Aquatic Food Webs[edit]

  • The removal of the dam restored natural sediment and wood delivery to downstream habitats, enhancing physical habitat complexity and nutrient levels. Algae, a primary food source for benthic invertebrates and young salmon, benefited from oceanic nutrients carried by returning adult salmon. Initial disruptions from suspended sediments during dam removal were followed by rapid invertebrate recolonization.


  • What do we want to know about the dam removal?


  • 2011 - Start of construction
  • 201# - End of contruction