Highway 37 bridge project in Novato gets $25M influx

A plan to raise a bridge in a flood-prone area of Highway 37 in Marin County is in line for a $25 million funding boost.

The Transportation Authority of Marin is set to transfer the funds to the California Department of Transportation for the Novato Creek Bridge replacement project. The funds are part of the county’s share of Regional Measure 3 bridge toll revenue administered by the Metropolitan Transportation Commission.

“What’s exciting about the new Novato Creek Bridge is that it’s going to be the first component of the entire 21-mile Highway 37 corridor that is constructed at the ultimate height,” said Marin County Supervisor Eric Lucan, whose District 5 includes Novato. “We’re going to see that segment right here in Marin, in an area that has experienced a lot of flooding and forced closures. We’re looking forward to it.”

Lucan is chair of the Transportation Authority of Marin board and a Marin representative on the State Route 37 policy committee. He said the TAM board is expected to approve the allocation at its meeting on Jan. 22. The allocation request would be submitted to the Metropolitan Transportation Commission for approval.

The plan to overhaul Highway 37 is a massive project, broken into several components, including some interim solutions. Ultimately, Caltrans will need to raise the entire road, an undertaking that is years away and expected to cost billions of dollars.

Caltrans is set to begin with the Novato Creek Bridge given its flooding problems, which have caused full highway closures since 2017 and headaches for tens of thousands of commuters. The bridge replacement is the first phase of a project to address flooding in the area of Highway 37 from Highway 101 to Atherton Avenue.

Phase one, at a cost of $270 million, involves constructing a new 26-foot-high bridge that can accommodate projected 2130 sea levels. The existing bridge deck is approximately 9 feet.

“The project is in the final stages of design, which will complete by the end of spring,” said Geoffrey Johnson, a Caltrans spokesperson.

Johnson said the Transportation Authority of Marin is a core partner in the effort to make the highway resilient to rising water. He said the $25 million allocation will support the addition of a 14-foot-wide multiuse path across the span.

“This path is a key feature that will enhance public access and safety for cyclists and pedestrians,” Johnson said.

Caltrans aims to begin construction in the spring of 2027 and finish in 2030.

The project is also supported by $155 million from the federal Infrastructure Investment and Jobs Act and $90 million in state funds.

The second phase, a $1.7 billion project, has yet to be funded. It would rebuild the remaining sections of the 2.5-mile portion of the highway as a 114-foot-wide, 35-foot-tall causeway, including a bicycle and pedestrian path.

“This first segment of the Highway 37 corridor plan has really been done well,” said U.S. Rep. Jared Huffman, a Democrat from San Rafael. “They’re elevating Highway 37; they have integrated SMART; there are going to be all kinds of multiple benefits.”

Huffman has been critical of Caltrans’ handling of other project components, including the three-phase, $500 million Sears Point-to-Mare Island project. That effort, an interim solution, will widen the highway to two lanes in each direction and fortify a portion of the San Pablo Baylands.

The project involves replacing the Tolay Creek Bridge, east of the Highway 37 and Highway 121 interchange, and extending an eastbound merge lane for a mile. The project also will restore a 3.5-mile section of degraded tidal salt marsh called Strip Marsh East to help protect against flooding while creating habitat.

Workers will install a tolled eastbound lane and widen the Sonoma Creek Bridge. Westbound improvements would be completed in a third phase.

The project is expected to withstand sea-level rise projections through 2050 and improve travel time and reliability. Construction is expected to begin in the fall and continue through winter 2030.

Huffman said the cost is too high for too little benefit.

“It’s going to be obsolete within 15 years of completion, and they’re going to add insult to injury by tolling everyone to drive on it,” Huffman said. “It’s really poorly conceived, unfortunately. And they’ve missed an opportunity to elevate it with a causeway that could open the door to the largest wetland restoration on the West Coast.”