A plan to collect tolls on Highway 37 is generating criticism about whether the cost burden would be spread equitably.

Caltrans held a public hearing in Vallejo on Tuesday night on a project to ease traffic and fortify wetlands between Sears Point and Mare Island. Project leaders reviewed the updated plans, including the restoration of a strip of salt marsh, and the recently released supplemental environmental review.

Attendees at the meeting said plans for a toll structure would affect those traveling west to work, raising questions about commitments to equity. The toll structure would be just east of Highway 121 in Sonoma County.

“Imagine for a minute a few years hence this current plan is enacted,” said Vallejo resident Paul Tice, a member of the Solano County chapter of the Sierra Club. “A wealthy person leaves their luxury residence in Marin and drives to their vineyard in Sonoma. They drive along an elevated roadway from Novato to Sears Point and turn left on Highway 121 at no extra cost to themselves.”

“Meanwhile, a gardener from Vallejo arrives at the mansion in their pickup with their tools,” Tice said. “They’ve had to pay an extra toll because they’ve driven across the eastern part of 37. Later a house cleaner from American Canyon arrives at the mansion. They’ve also had to pay a toll because their work day requires them to move house to house.”

“Solano and Napa county users will pay a toll to help with the cost of road improvements,” he said. “Marin and Sonoma users will get their road improvements at no extra cost. The current tolling plan is blatant discrimination against lower-income workers who have been prevented from living closer to work in the western counties by decades of exclusionary zoning.”

Monica Brown, a Solano County supervisor, said, “My contention is that if you’re going to charge anybody — if I have a truck with me because I need to paint somewhere — I shouldn’t have to get charged. That’s not fair.”Kevin Chen, assistant director of the Metropolitan Transportation Commission, noted that anyone traveling from Marin to Solano would pay the toll.

The area is notorious for traffic congestion, especially for drivers traveling east in the afternoon. Detours around the route double the distance.

The 10-mile project will widen and lengthen the Tolay Creek Bridge and add a carpool lane in each direction in an effort to reduce traffic congestion. The carpool lane will be toll free, but those traveling alone will pay a toll.

The project also will restore a 3.5-mile section of degraded tidal salt marsh, called Strip Marsh East, to help protect against sea-level rise and flooding while creating habitat.

“I acknowledge that there’s challenges with equity in the implementation of our projects, but we are driven in the near-term project with the need to manage vehicle miles traveled and the state’s requirements,” said Jeanette Weisman, the project manager with the Metropolitan Transportation Commission.

Weisman said that under state regulations, if a lane is added then other measures have to be taken to ensure that more vehicles — and more greenhouse gas emissions — are not being added.

“I understand vehicle miles traveled and I understand saving critters, but why does it have to come at our expense?” Brown said. “A toll is supposed to take care of bridges and a road.”

The proposed location for the toll structure is 400 feet east from the Tubbs Island trailhead intersection in Sonoma County, said Skylar Nguyen, a Caltrans scientist. She said the location was chosen to avoid environmentally sensitive areas and reduce the environmental impact.

The tolls wouldn’t be operational until the lanes are open to traffic and new toll discount programs and expanded public transit programs are active.

Chen said the tolls will only pay for part of the project, and also encourage carpooling. The toll revenue would be used to help fund a larger, longer-term project to elevate the entire stretch of road. Tolls would not be collected until the project was finished.

“The location that’s proposed is because we’re trying to locate the toll gantry, I guess lining it up with the portion of the corridor that’s going to get the most improvements,” Chen said.

Nguyen said the project would be done in three phases. Phase one, which includes the work on Tolay Creek Bridge, would begin in 2026 and end in 2027. The second phase, involving the addition of an eastbound lane and the Strip Marsh East restoration, would begin in 2027 and end in 2029. The last phase, which would add a westbound lane, also would begin in 2027 and end in 2029.

“One note is that this schedule is dependent on the funding availability, especially for phase two and three,” said Nguyen, who added that the presence of special status species could also restrict construction.

About $100 million of the $500 million needed for the project has been raised.

The draft supplemental environmental report is open for public comment until Feb. 3. The final report is expected this spring.