Restoration using dam removal is attracting growing interest and application. As dams age, managers, policy makers, and the public face choices about maintaining, refitting, or removing outdated structures. In 2009, a historic restoration project will begin on Washington’s Olympic Peninsula with the planned removal of two Elwha River dams in place for over 90 years. The Elwha River Restoration Project will represent the largest project of its kind ever attempted. The project will restore over 115 km of salmon spawning habitat, most of it protected within Olympic National Park. Prior to dam construction, the Elwha supported 10 distinct runs of anadromous fish including all 5 species of Pacific salmon. The spring Chinook were legendary for their size, with fish weighing as much as 45 kg. The dams changed almost everything. They have disrupted fluvial, floodplain, and ecosystem processes critical to maintaining properly functioning habitat for fish and other species. Successfully removing these dams will potentially have far-reaching implications for other large dam removals. This session will use the Elwha as a model system. Speakers will outline the Elwha ecological framework, the research coordination process, and the projects already underway gathering pre-removal baseline data. Following the recommendations of several planning workshops, these studies include: determining the population status and distribution of fish; tracking marine-derived nutrients; distribution of invasive plant species; stable isotope levels of carnivores; distribution and abundance of avian communities; and an assessment of nearshore geology, oceanography, and biological communities. Scientists from diverse agencies and institutions are collaborating and coordinating these projects through an NSF-funded Elwha Research Consortium. To consider the broad ecological scope of dam removal effects, speakers will address riparian restoration from diverse perspectives. These perspectives will include: aquatic, marine, and terrestrial zones; abiotic components, producers, and consumers; ecosystem function and organism-based views; and ecological forecasting post dam removal. The session will present diverse research approaches to inform large dam removal and river restoration programs. Many lessons from the session will be broadly applicable to restoration projects involving large dams. These lessons will include: 1.The importance of baseline data prior to restoration, and strategies for obtaining those data with limited time and resources. 2.Integration and coordination among research groups. 3.Direct and indirect linkages in space and time. 4.Interactions between biotic and abiotic components. 5.Approaches to bound uncertainties in restoration forecasts. 6.Forecasting and addressing undesired effects of dam removals.