Environmental Services is designing a project to replace an aging culvert on Fanno Creek at SW 45th Avenue. The new, larger culvert will improve stream flow and allow fish to pass through.
The existing culvert is a four foot wide, four and a half foot tall concrete box that is too small and can cause the creek to back up and flood during very heavy rain storms. The culvert also makes the creek flow much faster when it rains, lowers creek depth in dry weather, and has a drop on the downstream side, all of which make fish passage difficult.
This undersized culvert at SW 45th Avenue is too small for current streamflow and hinders fish passage.
The new culvert will be a wider bottomless stream simulation culvert. The project will include work to stabilize Fanno Creek’s banks downstream and upstream of the culvert, and some floodplain restoration. Environmental Services will also construct stormwater facilities along SW 45th Avenue to capture and filter stormwater runoff before it flows into Fanno Creek.
The 2005 Fanno and Tryon Creeks Watershed Management Plan recommended this project to improve watershed health. The restoration work and fish passage improvements will continue Environmental Services efforts to improve conditions in Fanno Creek.