For over a decade, Stillwater Sciences has been actively involved in advancing the science behind dam removal as a restoration approach, including contributions at national workshops on dam removal. We use models and site-specific field data to provide our clients with a comprehensive understanding of the short-term and long-term physical and biological impacts of dam removal at varying spatial scales. This information is then used to determine likely impacts on valued native flora and fauna and the potential for downstream flood risk, and so allow stakeholders to understand the competing issues and benefits of dam removal. Our goal in these analyses is to provide the most cost-effective and ecologically-sound method for removing dams, specifically tackling the issue with the following tools and approaches:
Our customized and tailored sediment transport models can be used to:
We use a UC Berkeley/NCED flume research facility in Berkeley, CA to conduct research projects that:
Pre- and Post-Removal Monitoring
We use standardized monitoring techniques for physical and biological variables to:
Planning and impact assessment
Understanding short- and long-term impacts of dam removal at various spatial scales allows us to develop dam removal plans that meet project-specific ecological goals. This impact assessment can include:
Removal of Marmot Dam, Sandy River, Oregon in 2007. Photo courtesy of Don Ryan.
Stillwater biologists have been conducting various aquatic monitoring efforts associated with the settlement agreement, signed nearly a decade ago, but has experienced many delays. We are assessing fish passage both before and after dam removal. See our photo time series of the breach here.
Observations made one year after dam removal indicated that the sediment transport predictions made 8 years prior to dam removal were broadly accurate, including the process of reservoir erosion and downstream channel aggradation, the low suspended sediment concentration associated with dam removal, and the quick restoration of fish passage. View full case study.
Stillwater Sciences is currently evaluating the sediment transport dynamics associated with the proposed removal of the 10-ft high Simkins Dam and the 34-ft high Bloede Dam on the Patapsco River, Maryland using the DREAM-1 model. Simkins Dam is scheduled for removal in 2010, and Bloede Dam will be removed at a later date.
With a settlement agreement recently reached, and final federal approval pending, decommissioning four dams on the Klamath may become the nation’s largest and most complex dam removal project. Stillwater conducted studies to assess the impacts of sediment transport following dam removal on the Klamath, including evaluating potential effects on fish and water quality. Our studies show that impacts of releasing the millions of tons of fine sediment stored behind the dams will be relatively short-lived and will not likely eradicate any species.