This proposed project will rehabilitate the American River Bridge along SR-51 by replacing the existing concrete bridge deck, replacing steel girder post-tensioning systems in spans 1 and 2, install sheet piling to cofferdams as well as installing steel piles to expand bridge piers and bents, dredging streambed material in the American River for floating barge access, widening the bridge to accommodate a Class 1 bike/pedestrian path and future transportation needs, widening the bridge abutments and roadway approaches, replacing and modifying an existing reinforced concrete box culvert to accommodate the road widening, and modifying an existing sound/retaining wall. Ultimately the project will involve widening the substructure and superstructure by approximately 55 feet along the northbound route of SR-51.
The Project will result in impacts to 4.939 acres of Chinook salmon (Oncorhyncus tshawytscha) (Spring-run of the Sacramento River drainage) habitat including temporary impacts to 4.483 acres. The Project will permanently remove 0.456 acres of spring-run Chinook salmon habitat. The project is expected to result in incidental take of spring-run Chinook salmon, which are designated as a threatened species under the California Endangered Species Act. The ITP referenced above as issued by CDFW authorizes incidental take of species listed under CESA that may occur as a result of Project implementation.