The board of supervisors for the County of Sonoma in California has awarded the contract for a seismic retrofit of the historic Wohler Road Bridge, which lies 16.1km north of Santa Rosa to local provider, Ghilotti Construction Company.

The one-lane steel bridge was completed in 1922 and does not comply with present day seismic design standards. The deck will be replaced with a lightweight concrete one. The bridge will also be fitted with seismic isolation bearings and joints, and the steel trusses and foundations will be reinforced.

The project, due for completion in 2025, will meet state requirements while preserving the bridge’s historic and architectural appeal in response to extensive community interest. It is funded by the Federal Highway Bridge Program.