Fine sediment deposition from Clark Canyon Creek has affected fisheries in the Beaverhead River during years when peak flow releases from Clark Canyon Dam are insufficient to transport the additional tributary sediment. Limited releases during the spring have allowed fine sediment to deposit in the Beaverhead River, which has affected the trout fishery downstream from the dam. Reclamation did a study to investigate flow releases from Clark Canyon Dam that would help mobilize and transport fine sediment from the streambed. An annual program of short-duration, high-flow releases from Clark Canyon Dam are expected to flush fine sediments from the streambed and result in improved habitat conditions for trout.
The East Bench Unit Joint Irrigation Board, Bureau of Reclamation, and Montana Fish, Wildlife & Parks worked collaboratively to release a flushing flow from Clark Canyon Reservoir between May 4th and May 8th in 2017 to mobilize fine sediment deposited into the Beaverhead River by Clark Canyon Creek. This management action was developed and made possible by the Beaverhead Watershed Committee and their longstanding work and dedication towards developing local, collaborative solutions to watershed health issues and a strong willingness by the East Bench Unit Joint Irrigation Board and the Bureau of Reclamation to partner in finding unique solutions to difficult problems. Click here to view Beaverhead Flushing Flow Report