Upstream Fish Passage at Cushman Hydro Project: Challenges and Updates

Tacoma Power owns and operates the Cushman Hydroelectric Project on the Skokomish River, Washington. Construction on the upstream fish passage facilities at Cushman No. 2 Dam was completed in 2014. Adult facilities are comprised of a fish pool, hopper, tram, and a sorting facility. Entry into the fish includes passage through a vertical slot, crowding into a hopper and transportation 230 vertical feet via tram into the fish sorting facility. Discharge through the North Fork Skokomish River (<300 cfs passes through or under the fish collection pool which is designed to evenly diffuse upwelling water. Prior to completion of the upstream fish passage facility, a natural barrier was identified approximately 2 miles downstream from the dam. Little Falls represents a culturally significant site to the Skokomish Tribe and the falls are in a difficult to access steep canyon reach. Tacoma initiated a two year alternatives analysis and design process taking into consideration perspectives from all stakeholders. The project to carve two fish ladders into existing rock material was completed in the summer of 2014, and the first adult salmon were observed above the falls in the fall of 2014.