Lane Reductions For Week of November 2 State Route 37 – Petaluma River Bridge, Marin County

Monday, Nov. 2 until morning of Saturday, Nov. 7
Construction Project Duration-October 2026-Tentative July 2028

Marin County - Caltrans is continuing a structural rehabilitation project on State Route 37 (SR-37) at the Petaluma River Bridge, at the Marin-Sonoma County line. The week of Monday, Nov. 2 work will require weekday and weeknight single-lane reductions.

On Monday, Nov. 2 one lane in the westbound direction will close from noon until about 6 a.m. next morning, and one lane in the eastbound direction from 7 p.m. until 6 a.m. next morning.

From Tuesday, Nov. 3, through Friday, Nov. 6, one of the two lanes in each direction of SR-37 on the bridge will be closed from 7 p.m. to 6 a.m. the following mornings.

The lane closure will allow crews to remove the old median pavement and repave it with new asphalt. Traffic will be shifted onto the median, where temporary concrete barriers will be placed to separate eastbound and westbound traffic. Another row of temporary concrete barriers will be installed along the eastbound to create space for the next stage of work, which involves removing the eastbound outside bridge barriers.

The entire project is expected to take approximately two years, depending on weather and other field conditions.

Work will include rehabilitating the bridge deck and upgrading the bridge barriers and railings to meet current safety standards.

This project focuses on rehabilitating the SR-37 Petaluma River Bridge and does not directly address long-term efforts to protect SR-37 from sea level rise.

Separate projects to reconstruct the nearby SR-37 Tolay Creek Bridge and SR-37 Novato Creek Bridge are tentatively scheduled to begin in 2027.

In August 2026, the California Transportation Commission (CTC) approved more than $300 million to advance sea-level-rise resilience projects throughout the SR-37 Corridor. These efforts mark the first set of SR-37 Corridor resilience projects moving forward.

For the latest updates on work at the SR-37 Petaluma River Bridge, visit: State Route 37 Petaluma River Bridge Preservation Project | Caltrans

For updates on upcoming Resilient SR-37 projects addressing sea-level-rise improvements, visit: SR37 Corridor Projects | Caltrans