Dam Removal and Stream Restoration on Goldsborough Creek in Western Washington State

The U.S. Army Corps of Engineers — Seattle District, in conjunction with the Washington Department of Fish and Wildlife and Simpson Timber Company is developing plans and specifications for a dam removal and stream restoration project on Goldsborough Creek, which drains into Puget Sound near the town of Shelton, Washington. The restoration objective is to improve upstream and downstream passage of migratory fish with no adverse downstream impacts. Target species included chinook, coho, and chum salmon, and coastal cutthroat trout, and resident species such as bull trout. The project will remove a 70-year old, 11-meter high dam constructed of timber piles, concrete, and sheet pile and replace it with a series of 0.30 meter drops constructed using H-pile and concrete weirs. Boulders, rock, large-woody-debris, and vegetation will be used to provide bank protection and habitat features. Major design considerations include passage for anadromous fish, channel invert stability and local scour, vegetative bank stabilization, downstream hydraulic effects, and long term sedimentation effects. Project constraints included real estate, right-of-way, utilities, railroads, wetland impacts, timing of construction, fish passage during construction, and cost control. Tetra Tech ISG is currently under contract with the Corps to develop the construction plans and specifications. The project is currently scheduled to begin construction in the summer of 2000 and is expected to continue through the summer of 2001.