https://www.marinij.com/2025/07/05/transportation-authority-of-marin-approves-sea-level-plan/
Plans to protect Marin’s roads, paths and transit from rising seas have taken a major step forward with the approval of a new adaptation report.
Capping a two-year effort, the board governing the Transportation Authority of Marin voted unanimously to accept the 200-page document at its meeting on June 26. The report identifies seven focus areas in the county, along with several potential projects designed to defend the county’s transportation network from rising water.
Approval enables the agency’s staff to begin working with officials in the county’s 11 municipalities to implement policy changes and start developing projects, including elevating roads and restoring marshlands.
“This is really intended to be more than just another study that sits on the shelf,” Anne Richman, executive director of the Transportation Authority of Marin said at the meeting. “There’s a lot of technical data behind the actual report, and we really want it to be useful to the jurisdictions.”
The authority is Marin County’s traffic congestion management agency and administers sales tax and vehicle registration fee collection through Measures AA and Measure B. The Measure AA sales tax measure, renewed by voters in 2019, allots 1% of its revenue, or $250,000 annually, toward sea-level protection.
The planning effort is the first sea-level project funded by the program.
According to regional agencies, Marin County is facing about $17 billion in expenses to build adaptation projects, such as elevated roads, living shorelines, marshes and potentially seawalls and levees, to protect itself from inundation.
Marin’s jurisdictions are working to develop their own subregional adaptation plans to comply with Senate Bill 272. The bill requires coastal communities to develop sea-level-rise plans by 2034.
The seven focus areas include Sausalito; Tamalpais Junction and Marin City; Mill Valley; the Corte Madera Creek watershed; San Rafael’s Canal neighborhood; Santa Venetia; and Novato. The report provides detailed adaptation summaries that highlight the flood-prone roads and infrastructure and the best types of projects to mitigate risks.