SR 131 Capital Preventive Maintenance

Project Overview

Caltrans District 4 (Bay Area) is in the design phase of the State Route 131 (SR-131) Capital Preventive Maintenance Project in the town of Tiburon.

Caltrans reached 95 percent design on Feb. 28, 2025 and is scheduled to reach full design by mid-summer, 2025.

The purpose of the project is to improve serviceability and ride quality on SR-131 and restore existing drainage systems to reduce the potential for highway flooding and to increase the safety for the public.

In addition, the project will enhance and complete streets and support active modes of transportation by bridging a gap in the transportation network and improve bicycle access throughout the area.

The location is approximately 1,000 feet west of US-101 interchange to the Tiburon Boulevard/Main Street intersection.

The project is broken down into three segments: The western segment includes Class I, II and IV bikeways, intersection modification as well as curb ramps, pedestrian refuge islands and sidewalk modifications. The central segment includes Class II and IV bikeways and intersection modifications. The eastern segment includes intersection modifications.

The Draft Environmental Document (DED) for the project was released and Caltrans held a public comment period from Sept. 29 through Nov. 3, 2023. The link to the DED can be found here: https://bit.ly/3FoHdsj

Project Schedule

The final environmental document was released in January of 2024.
The final design phase is scheduled for the summer of 2025.
Construction is set to begin in the winter of 2026.
The project is scheduled to be completed in the winter of 2027.

Project Contact

Matt O’Donnell
Marin County Public Information Officer
Email: matt.odonnell@dot.ca.gov
Phone: (510) 852-5113