Marin City Second Culvert Project
Project Overview
Flooding affects the entire California Highway System, and Caltrans is looking for ways to mitigate the issue, especially with sea-level rise expected to affect the region in the next 100 years.
With the Second Culvert Project on US-101 in Marin County, Caltrans proposes to build a 6-by-4 culvert that will help mitigate flooding in the Marin City area. The location is near Marin City from Donahue Street to 0.3 miles north of Donahue Street.
The Draft Environmental Document (DED) for this project is scheduled to be circulated externally in June, 2025.
Environmental Documents
- Initial Study with Proposed Mitigated Negative Declaration
- Section 4(f) Evaluation Technical Memorandum
Caltrans Informational meeting
About 30 members of the community (in-person and online) attended a public meeting for the Marin City Second Culvert Project on Wednesday, June 18 at the Marin City Senior Center.
Submit a comment in writing during the public comment period, from Wednesday, June 4 to Monday, July 7, 2025.
Send by mail to:
Caltrans District 4, Office of Environmental Analysis
ATTN: Christopher Pincetich,
P.O. Box 23660, MS 8B
Oakland, CA 94623-0660
Or by email to:
Marin City Second Culvert Project Public Meeting 6/18/25
Project Schedule
The project is scheduled to go into construction in 2027.
Caltrans is coordinating with Marin County and the Marin City Stormwater Task Force, which includes a county project, permanent pump station and floodwall within project limits. These Marin County projects are not part of this project. Please contact the county for more information.
Please send questions to marin_city_second_culvert_project@dot.ca.gov
Marin City Second Culvert Project Video
Project Contact
Matt O’Donnell
Marin County Public Information Officer
Email: matt.odonnell@dot.ca.gov