In 2000, the Department of the Interior (DOI) purchased Elwha and Glines Canyon dams, impounding the Aldwell and Mills Reservoirs on the Elwha River in Washington State. These two dams are to be removed to support river habitat restoration. Approximately 24 million cubic yards of sediment are being managed as part of the dam removal project. Monitoring shifting topography that occurs as the sediment is eroded and redistributed downstream is critical for adding to the science of dam removal. Reclamation partnered with the U.S. Geological Survey (USGS) in 2012 to test the feasibility of using the Raven® UAS with a GoPro Hero 2 camera to map this dynamic topography. From the point cloud generated from the Hero 2 photography using PhotoScan software, USGS scientists successfully generated imagery mosaics and digital elevation models (DEMs) of both Aldwell and Mills Reservoir sediments. These DEMs will help river restoration scientists and engineers manage river flows to optimize sediment transfer as the dams are removed.
Mills Reservoir Sediments September 2012