Marin Narrows portion of Highway 101 gets $76 million funding boost to begin work

The final leg of a $1.2 billion, North Bay Highway 101 widening project received a boost Wednesday, as the Metropolitan Transportation Commission approved a contingency funding plan for the Marin County Narrows portion of the work.

The commission’s decision to use federal regional discretionary funds to funnel up to $76 million to the Transportation Authority of Marin for widening work north of Novato comes six months after the project secured a $40 million state grant, and officials say it ensures the timely completion of the largest road project in the North Bay in a generation.

“I think it saves 12 months if not two years,” said Sonoma County Supervisor David Rabbitt, who also serves on the MTC. “They couldn’t put it out to bid without the money in the bank to pay for it. Now they can do that instead of waiting.”

Work is expected to begin soon, and transportation officials have circled late 2023 or early 2024 for completion of the Marin Narrows, the final stage of a massive highway widening project that will ensure six lanes of Highway 101 from Windsor to Sausalito.

In the Narrows alone, which includes ongoing work on a $121 million, 3-mile segment from Corona Road to the Petaluma River, the project is expected to cost $754 million.

The unfinished section of the Narrows in Marin County includes a 6-mile segment along southbound Highway 101 and a 3½-mile northbound segment south of the county line. The total cost is nearly $136 million, with additional funding coming from a variety of local sources, including earmarked sales tax.

Rabbitt said the project was necessary not only to relieve congestion, but to increase safety.

“If you look at the freeway project overall, it’s a much safer (system),” Rabbitt said. “There were dozens of driveways onto the highway south of Petaluma. We were the last ones on a corridor served by a single road like that – the last ones to go from highway to freeway.”

The Metropolitan Transportation Commission’s accounting maneuver Wednesday replaces, at least for now, money collected from voter-approved toll increases that remain at the center of a lawsuit filed by the Howard Jarvis Taxpayers Association. That lawsuit is now awaiting a hearing before the California Supreme Court, and if the state’s highest court sides with lower courts in rejecting the challenge, it would free up $90 million initially set aside for the Marin Narrows work.

In a potentially risky decision, which officials say is backed by confidence in the regional transit agency’s case, the Transportation Authority of Marin has agreed to pay back the MTC only if the court rules against the taxpayer group.

The lawsuit is centered on a voter-approved ballot measure that hiked by $1 tolls on seven state-owned bridges, not including the Golden Gate Bridge. The increase began in 2019, and is set to expire in 2025, collecting $4.5 billion for road and transit upgrades throughout the region.

A win for the Metropolitan Transportation Commission would bolster a host of local projects, including freeing up $100 million for Highway 37 improvements and $40 million for the Sonoma-Marin Area Rail Transit system’s 3-mile extension to Windsor.

With the court ruling in flux, Rabbitt said the MTC had just moved the project one step closer to completion.

“This project, with the history…20 years later, to have this last piece as the gap…this is a really solid move forward to get that piece in the middle of the Narrows complete,” Rabbitt said.

Tyler Silvy is editor of the Petaluma Argus-Courier. Reach him at, 707-776-8458, or @tylersilvy on Twitter.

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