Highway 37 improvement plan eyed by Marin, other North Bay counties

By Mark Prado

Marin and other North Bay counties are looking to develop a plan and financing to improve the utilitarian and sometimes aggravating Highway 37 between Novato and Vallejo.

Increasing traffic and sea-level rise are among the challenges facing the state highway, which existed in its current footprint since the 1930s.

Today some 40,000 vehicles a day use the 21-mile-long highway that skirts the northern shore of San Pablo Bay, delivering commuters and goods to their destinations.

“It’s a big trade corridor carrying products from the Central Valley to Interstate 80 and then the North Bay,” said Dianne Steinhauser, who heads the Transportation Authority of Marin. “It’s an important roadway.”

But it has numerous issues.

While the Marin portion has two lanes in each direction, it narrows to one lane each way just past Sears Point. That makes for heavy traffic during commute hours and gets even worse when there are race car events at Sears Point.

“It can be like sitting in a parking lot,” acknowledged Steve Williams, Caltrans spokesman.

Because it sits so close to the bay and wetlands, the highway is also vulnerable to flooding during heavy storms, which cause repeated closures.

“We see a lot of flooding on the Novato and Marin side,” Steinhauser noted. “It can be a battle to keep it open in heavy storms.”

Additionally, two separate studies show Highway 37 is vulnerable to projected sea-level rise, making it more likely to experience increased flooding and frequent repairs. Caltrans is working with the University of California at Davis Road Ecology Center on the issue.

The highway is also affected by the continual settling of the roadway from unstable soil beneath and heavy truck traffic, which can cause undulations on its surface. The Highway 37 interchange with Highway 101 in Marin is also an area for improvement, Steinhauser said.

Now Marin County is set to join Sonoma, Napa and Solano counties to look at ways to provide fixes for the highway while seeking funding sources. The counties are expected to sign a memorandum of understanding in the coming weeks to study Highway 37 improvements.

“We want to start to look at this as a group because it affects all of us,” Steinhauser said. “By working together we may be able to better identify money for work. It’s the beginning of a long process.”

Widening two-lane sections to four lanes, improving the road and making it flood-proof won’t be cheap. Some estimates of an overhaul to the highway have topped the $1 billion mark.

There has been some suggestion that Highway 37 become a toll road to help pay for improvements. One improvement and funding option has been presented by a private consortium, Foster-City based United Bridge Partners, to finance and build the project.

Whatever happens, drivers should not expect to see changes anytime soon.

“We are talking in the five- to seven- to 10-year range at best,” Steinhauser said.

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