The Luther Road project area (near SE 76th Avenue and SE Bell Avenue in Portland, Oregon) has undergone several geomorphic changes since former habitat enhancements were constructed in 2014.
Johnson Creek moved laterally in several areas and incised, exposing the Lents interceptor and damaging constructed grade control structures. It created gravel bars and exposed large woody debris.
In response to the geomorphic changes and risk to infrastructure at this site Portland BES hired W2r to re-design more resilient infrastructure protection and habitat improvements. This included a sewer pipe and trail infrastructure, restoration of the adjacent floodplain, and improving the functionality of adjacent stormwater outfalls.
Key to developing robust, as well as habitat-forward engineering solutions, was considering the floodplain rather than just the channel.
The design broadened the grade control structure (roughened channel) by 300%; minimized the slope and associated hydraulic forces along the roughened channel; and incorporated embedded habitat logs, pre-built scour pools and boulders for energy dissipation, and other habitat elements to improve fish passage, habitat cover, and hydraulic diversity.
Client
Portland Bureau of Environmental Services
Keywords
Urban stream restoration, floodplain connectivity, trail and sewer infrastructure protection, geomorphic assessment, hydrologic and hydraulic modeling
Location
Portland, OR (Reeder Road, mile post 7 on Sauvie Island)
