This project will replace the two existing culverts under SR 20 in the town of Concrete located in Skagit County with fish passable structures. The existing concrete culvert at Fish Creek (MP 87.82) was installed in 1951. It will be replaced with a new four-sided box structure that is 19 feet wide to provide fish passage underneath SR 20. The existing 18 inch concrete culvert was replaced later with a 24 inch corrugated metal pipe that has accumulated significant erosion. Emergency repairs were completed in May 2018 to a sink hole that formed above the downstream culvert adjacent to the east shoulder. The existing culvert at Lorenzan Creek (MP 87.78) will be replaced with a new three-sided, bottomless, fish passable crossing that is 16 feet wide by 46 feet long. The proposed replacement is designed to provide a long term solution to future scouring and erosion of the stream bed.
At the end of construction, the traffic diversion will be removed and the temporarily disturbed areas will be revegetated with native species. Additionally, the project proposes to leave pavement behind on top of the trail for a betterment to future trail users to better accommodate bicyclists, pedestrians and other non-motorized equipment.
Why we are removing fish passage barriers
State highways cross streams and rivers in thousands of places in Washington State, which can impeded fish migration. WSDOT has worked for nearly three decades to improve fish passage and reconnect streams to help keep our waterways healthy. WSDOT Fish Barrier Correction is a priority.