Route 37 Closure for SMART Train Track Repair

Detour map.

32-Hour Weekend Closure of State Route 37 in Sonoma

For Railroad Track Repair


Closure from Saturday, May 20, at 3:00 AM – Sunday, May 21, at 11:00 AM 


SONOMA COUNTY - Caltrans in coordination with Sonoma-Marin Area Rail Transit (SMART) has scheduled a closure of State Route 37 (SR-37) just east of State Route 121 (Arnold Drive) from Saturday, May 20, at 3:00 AM, until Sunday, May 21, at 11:00 AM, to allow SMART to repair a railroad crossing on the highway. The rails and subgrade need significant repairs due to wear and tear from decades of cars and trucks passing over.


Traffic will be detoured around the closures.


Eastbound traffic from Marin County may travel as far as SR-121 (Arnold Drive). Westbound traffic from Solano County can travel as far as Walnut Avenue in Vallejo before diverting onto city streets.  



Detour details:

  • Motorists heading westbound will take Highway 29 to Highway 12, then take Highway 121/Arnold Drive to Highway 37.
  • Motorists heading eastbound will take Highway 121/Arnold Drive to Highway 12, then Highway 29 to Highway 37. Westbound drivers may also continue on Highway 12 to Interstate 80.


Work crews will place detour signs and electronic message signs along Highway 29, Highway 12, Highway 121/Arnold Drive, and Highway 37 approximately two weeks before the road closure.

For more information on the SMART track replacement project go to:

Or contact Matt Stevens: