For nearly 100 years wild salmon populations along the Elwha River, located at the heart of Olympic National Park, have been limited to a five-mile stretch of the 45 mile-long river below the Elwha and Glines Canyon dams. In September 2011 engineers began the Nation’s second largest ecological restoration project; a three-year dam removal process, allowing wild salmon and other anadromous fish populations to return to the upper channels and tributaries of the river. But how effective will these restoration efforts be, and how do we measure success? Kinsey Frick, George Pess, and John McMillan, scientists from the Northwest Fisheries Science Center in Seattle, Washington, in partnership with other federal, state and tribal organizations in the region are working together to find answers to these important questions. Their research will not only help us understand the impacts of dam removal on wild salmon populations and ecosystems in the Elwha and allow managers to manage the recovering system adaptively, but also help inform future river restoration projects throughout the country.