Welcome to Caltrans District 4

Planning Studies

State Route 37 Integrated Traffic, Infrastructure and Sea Level Rise Analysis

The State funded State Route 37 Integrated Traffic, Infrastructure and Sea Level Rise Analysis study was completed at the end of February 2016. The University of California, Davis was the lead and AECOM was the sub-contractor. Key stakeholders included: Congestion Management Agencies from Napa, Solano, Sonoma, and Marin Counties, the Metropolitan Transportation Commission, the North Bay County Resource Conservation Districts, State and Federal resource and permitting agencies, Sonoma Ecology Center, Sonoma Land Trust, and numerous others.
The study provided crucial information on the expected impacts of sea level rise on Highway 37 and developed high-level cost estimates for adaptive road/structure designs to help decision-making on the future of the facility. Three roadway adaptation options were studied:

Roadway elevated on a box girder causeway (rendering, AECOM)

Roadway elevated on a slab bridge causeway (rendering, AECOM)

Roadway elevated on a berm/embankment (rendering, AECOM)

Cost estimates for reconstruction of the highway to account for higher sea levels ranged from $1.2 billion to $4.3 billion. This major undertaking can only be accomplished with local, regional and state and federal partners working together on innovative funding options such as a Public-Private Partnership, for example.


Final Report

CURRENT SR-37 EFFORTS UNDERWAY (Solano Transportation Authority)


Please direct your comments to:
Ina Gerhard, Supervising Transportation Planner
Chief, Office of Transit and Community Planning
Phone: 510-286-5598
Email: ina.gerhard@dot.ca.gov