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State Route 12 Corridor Map

http://www.corridormobility.org/imgManager/1000000582/sr12_web.jpg

Connecting the Bay Area to the San Joaquin Valley

SR-12 is a mostly rural, two to four-lane route that supports interregional, recreational and commuter traffic between the Bay Area and the San Joaquin Valley.  SR-12 is important for recreational travelers destined for Napa and Sonoma Counties as well as the Delta. It also serves as a commute corridor and a key interregional goods movement corridor because of its direct access to I-80.


Concerns about rising sea levels from the Delta Protection Commission and other agencies are causing Caltrans to take this issue into account for the safety and viability of the corridor. There is a great deal of sensitive habitat along this corridor as well.  Limited transit service is available along SR-12, with intercity rail connection at Suisun City.  This route also provides access to airports in Napa and Rio Vista, as well as Travis Air Force Base.  There are few alternative routes to SR-12 connecting the communities along this corridor.

Corridor Specific Issues 

  • Key corridor connecting San Joaquin Valley, Delta and the Bay Area. 
  • Environmentally sensitive habitat and potential climate change impacts.
  • Congestion most often present during peak commute times and weekends.
  • Limited transit access; intercity rail access provided at Suisun City.
  • Access to air services at Napa Valley Airport, Travis Air Force Base and Rio Vista Airport.

Corridor Mobility Improvement Account (CMIA) Project

The CSMP requirement is noted in the Baseline Agreements of all projects receiving CMIA funding. CMIA funds have been allocated for the following improvement project on the SR-12 Corridor:

  • SR-12 Jameson County Widening 

Partners and Project Schedule

Caltrans is working in partnership with local agencies and groups to develop a CSMP for the State Route 12 Corridor, which runs 30 miles from the Jameson Canyon to the Solano/Sacramento County line. The corridor intersects SR-29, I-80, SR-113, SR-84 and SR-160.

  • Complete Draft CSMP (June 2010)
  • Adopt Final CSMP (Sept. 2010) 
View a copy of the SR-12 Fact Sheet by clicking here

For More Information, please contact:
Joseph Aquilar
Office of System Planning
District 4

joseph_aguilar@dot.ca.gov