State Route 70 Simmerly Slough Bridge Replacement

Project Facts


The Simmerly Slough Bridge on State Highway 70 north of Marysville no longer meets current design and seismic safety standards. The bridge also is experience scouring activity in which water has been removing sediment such as sand and rocks from around the bridge piers or abutments.

Project Benefits

  • Constructing a new bridge parallel and west of the current structure design and seismic safety standards.
  • Realigning the highway approaching the bridge on both ends.
  • Constructing the new bridge to accommodate five lanes in the future.
  • The new bridge will be striped for two lanes and provide for 8-foot paved shoulders, sidewalks on both sides and a concrete barrier separating the shoulder from the sidewalk and bridge railing.
  • Two traffic lanes will remain open throughout construction. The old bridge will be demolished after the new structure is completed.

Funding Breakdown

Local - none
State - $83,600,000
Federal - none
Estimated Total Project Cost - $83,600,000

Project Schedule

Environmental Clearance – June 2017
Right of Way Acquisition – May 2018
Begin Construction – Spring 2019



Project Contact

Cameron Knudson, Project Manager
Phone: (530) 741-4587

Gilbert Mohtes-Chan, Public Information Officer
Phone: (530) 741-4571


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