Voters hold key to complete Highway 101 widening through Sonoma-Marin Narrows

For motorists who traverse a traffic-plagued stretch of Highway 101 between Sonoma and Marin counties, it is the one shared question: When will the roadway expansion between Petaluma and Novato be finished?

The answer depends on a few financial and political factors, including what looks to be a looming fight at the ballot box over the future of California’s new gas tax to support transportation upgrades.

This month, the last piece of the funding puzzle fell into place for Sonoma County’s largest outstanding portion of the project, after the California Transportation Commission committed ?$85 million in gas tax dollars. Together with a remaining $37 million contributed from Sonoma County’s Measure M sales tax for transportation and the city of Petaluma, the money will complete the lane-widening from Corona Road to the Petaluma River by the end of 2022 - more than two decades since construction got underway to establish a third lane in each direction from the Marin County line to Windsor.

Current work south of the Petaluma River to just over the Marin County line is funded and is set for completion by the end of 2019.

But the widening project through the rest of the Narrows, to just north of Novato, remains an estimated $120 million short on cash.

And much of what remains to be done rides on the availability of both revenue from the gas tax - now subject to a potential statewide repeal - and a separate proposed toll hike for Bay Area bridges that voters will decide Tuesday. That toll hike, if approved, would raise $4.45 billion over the next 25 years for regional road improvements and mass transit projects.

The potential repeal of the gas tax authorized by Senate Bill 1 has transportation officials the most concerned. It would eliminate all future proceeds, plus, for Sonoma County, the $85 million already awarded by state transportation commissioners for highway widening in Petaluma.

“If the money were to disappear, it would be a huge impact,” said Suzanne Smith, executive director of the Sonoma County Transportation Authority. “It would be horrible. We would be in a world of hurt.”

A spokesman for the group behind the proposed ballot measure, “Give Voters A Voice,” which includes businessman and Republican gubernatorial candidate John Cox, said last week it submitted nearly twice the number of required signatures to state officials three weeks ahead of the deadline.

Meanwhile, the nine Bay Area counties have been lining up behind efforts to convince voters to approve Regional Measure 3 to raise tolls on state bridges, except on the Golden Gate Bridge, by $3 over the next seven years. Of the anticipated windfall, $120 million would go to the Highway 101 widening project.

A handshake agreement between Sonoma and Marin counties envisions an even split of those funds, according to Sonoma County Supervisor David Rabbitt. But if SB1 is kept in place, the bulk of that money could go to Marin County toward the funding shortfall to finish its portion of the Narrows about a year after Sonoma County.

“If you live in Petaluma, it doesn’t matter that it’s three lanes in Sonoma if it’s only two for the section in Marin County,” said Rabbitt, who plays a lead role in regional transportation issues. “We’re as big of advocates for Marin County as Sonoma on the freeway work, for sure.”

Until the SB1 money is in hand and heavy-duty machinery can begin work on closing the Petaluma gap, Sonoma County is left to hope voters continue their funding commitment to the project.

“We need SB1, and Regional Measure 3 to be approved, to actually complete the full corridor in a timely manner,” Smith said. “If it goes away, we’re left scrambling to align different stars, which makes costs go up and makes it even more challenging.”

You can reach Staff Writer Kevin Fixler at 707-521-5336 or at kevin.fixler@pressdemocrat.com. On Twitter @kfixler.