The Dungeness Fish Ladder project added a fish ladder to Canyon Creek’s 112 year old diversion dam – opening up two additional miles of habitat access for resident and anadromous fish species that had been blocked since 1903. The new fish ladder enables the dam to meet current fish passage standards while still providing an auxiliary water source for the Dungeness River Fish Hatchery.
Working within an in-water work window governed by the creek’s low-flow season, construction began in June with crews out of the water by the end of October. Using a turbidity curtain, crews first constructed a 160 foot, 36-inch diameter bypass system for the stream so that work on the dam could begin. Modifications to the dam included over 1,100 cubic yards of rock hammer excavation to prepare for the fish ladder and weir construction, 25 rock bolt installations, four weirs totaling 1,200 square feet, and a fish ladder approximately 55 feet long.