Highway 101 and Petaluma River Bridge

The replacement of the Petaluma River Bridge was part of the Marin-Sonoma Narrows Project commissioned to improve the safety and functionality of 16-miles of highway from State Route 37 in Marin County to Corona Road in Petaluma Since. The 60-year-old four-lane span over the river was rebuilt into a modern, six-lane, $130 million bridge. 

Our work also included construction of the Kastania Road Overcrossing, construction of four new ramps, two frontage roads, seven retaining walls, and the overall raising of the highway for sight distance improvements. Because Ghilotti Bros. was already working on an adjacent Caltrans project, we proposed phasing changes to incorporate both projects—rather than treat them as separate projects. Making these changes helped our team be more efficient all-around.


California Department of Transportation


Petaluma, CA


Public Works


Paving & Concrete