MTC News Release:
Legislature Passes Permitting Bill, Paves Way for Hwy. 37 Improvements
- North Bay Area Counties (Marin, Sonoma, Napa, and Solano)
- Caltrans
- MTC
- Regulatory Agencies
Planning a More Resilient
Highway 37 for All
Think about Highway 37 as more than just a commute! The future of this corridor demands finding solutions to chronic traffic congestion and periodic flooding. But it will also require balancing transportation needs with protecting and enhancing sensitive marshland habitats. Planning a long-term solution presents an opportunity to provide bicycle, pedestrian, transit, and carpool options for all travelers.
Meetings & Events
Upcoming State Route 37 Policy Committee meetings:
- September 3, 2026 9:30 am – 11 am – Marin County Board of Supervisors Chambers
Meeting Locations vary between Marin, Sonoma, Napa, and Solano Counties.
MTC Update:
Draft Supplemental Environmental Document
- Draft Supplemental Environmental Document (PDF) is now available for review.
- Public Comment Period: December 18, 2024 through February 3, 2025. Comments may be submitted via the following methods:
- Email to stateroute37@dot.ca.gov
Postal Mail addressed to:
Caltrans District 4
ATTN: Skylar Nguyen, Senior Environmental Scientist
P.O. Box 23660, MS: 8B, Oakland, CA 94623-0660
- Email to stateroute37@dot.ca.gov
- Public Comment Period: December 18, 2024 through February 3, 2025. Comments may be submitted via the following methods:
- December 2024: PEL Addendum
Caltrans is has prepared an addendum to the PEL Study to prioritize segments for future environmental review, design, construction, and implementation.
State Route 37 PEL Study – 2024 Addendum
View the stakeholder presentation slides: Presentation (PDF)
Get Involved
Get involved in planning Highway 37: resilient, reliable, safer, and built to last for all travelers!
To learn more about the planning processes and how to provide your valued input:
Resilient SR37 — Collaborative Roadway and Bayland Partnership
Sears Point to Mare Island
Flood Reduction Project
Planning & Environmental Linkages
Comprehensive Multimodal Corridor Plan
Design Alternatives Assessment
SR37 Policy Committee
SR37 Program Reports
Provide a comment or sign up for email updates
Call the Highway 37 Public Information Line
(510) 286-1204
One Corridor, One Team, Many Solutions
While Caltrans, the Metropolitan Transportation Commission, and transportation authorities for Marin, Napa, Solano, and Sonoma counties are already implementing short-term improvements, other challenges require a suite of longer-term solutions
A Collaborative Team of Agencies
Transportation Authority SR37 Pages
Transportation Authority of Marin
Napa Valley Transportation Authority
Project Study Areas
Click here for an interactive map to further explore the project study areas.
Learn More: Frequently Asked Questions
What is the Vision for Highway 37?
A long-term plan should last a generation or more. We need to anticipate changes in the landscape and the transportation needs of the region. Think of the people and the areas that Highway 37 serves, how the highway interacts with the built environment and wildlife, and how future residents will be using this area. That is where a vision starts.
How Will My Input Be Used?
The Highway 37 Team is seeking input from engaged stakeholders and members of the public to inform solutions and strategies. Your recommendations will be summarized and forwarded to transportation planners and highway designers.
A highway has many elements—alignment route, travel lanes, connection points, bridges, and waterway passages—with options for bicyclists, pedestrians, and transit. Highway 37 is affected by the surrounding landscape, including agricultural lands, natural habitat, and the built environment. What elements do you see as part of the solution and what considerations should be evaluated or protected? It’s One Corridor – many solutions! Your ideas will help shape these potential solutions, the evaluation, and the final project.
When Can We Expect These Improvements?
Our team is taking a phased approach; addressing the most immediate challenges now, while we seek your input on longer-term solutions. Work has already begun on some of the shorter-term solutions, including raising the roadway and installing floodwalls in areas most vulnerable to flooding. Another short-term project is reducing congestion through the addition of a high occupancy vehicle (HOV) lane between Highway 121 and Mare Island.
Medium- and long-term solutions will require more study and evaluation by engineers, regulators, and the public. The roadmap below outlines the primary planning phases and key milestones all the way through construction. As you can see, there will be lots of opportunities for public input throughout the process.
Who Can Participate in the Planning Process?
Everyone is encouraged to participate.
