Lower Bohannon Creek Culvert to Bridge

Project Narrative

The two side-by-side undersized, corrugated metal culverts used to convey Bohannon Creek, a tributary to the Lemhi River, underneath a private road created a fish passage barrier. The side-by-side culverts were removed and replaced with a 40’ span by 16’ wide prefabricated modular steel bridge. The final measurement for additional access for all life stages of ESA-listed revealed a deviation to the original proposed miles of access. The removal of the fish passage barrier resulted in 1.1 miles of a access (versus the 1.5 miles originally proposed) of unimpaired fish passage for all life stages of ESA-listed anadromous and resident fish species. Implementation, engineering compliance, salmonid and water quality were monitored during the project period at the worksite. Removing the two culverts will allow passage for all life stages of ESA-listed salmonids and restore a more natural condition to the Bohannon Creek channel at this location. Removal of this fish passage barrier will provide an additional 1.5 miles of access upstream. This project compliments other ongoing efforts upstream.