Officials narrow connector preferences for 101 to I-580

Officials have taken a step closer to narrowing options for a proposed freeway connector from northbound Highway 101 to eastbound Interstate 580.

Members of the San Rafael City Council, which received a project update on Nov. 15, generally supported continuing to study four out of nine alternatives based on community concerns about cost and impacts on the city. The Transportation Authority of Marin is leading the effort.

The preferred proposals included alternatives 2 and 6, which would exit Highway 101 midway down the bridge structure at the top of Cal Park Hill; and alternatives 3 and 3b modified, which would exit closer to Bellam Boulevard near Marin Square Shopping Center.

Anne Richman, executive director of the Transportation Authority of Marin, said the board will soon be asked to make a final decision in order to launch an environmental review of the project early next year.

As it stands, northbound Highway 101 drivers must use local streets in San Rafael or Sir Francis Drake Boulevard in Larkspur to get to the Richmond-San Rafael Bridge by I-580. The connector plan, still in the early stages of development, would link the two freeways for direct access to the bridge.

If there is no project, traffic is expected to get worse on northbound Highway 101 and Sir Francis Drake and Bellam boulevards.

Councilmember Maika Llorens Gulati said she wants more concrete numbers on traffic impacts so she can understand why making greater improvements on Sir Francis Drake Boulevard in Larkspur was not an option.

“The goal of this project is to make a freewayto-freeway connector that separates the local traffic from the regional traffic,” Richman responded. “And so making more improvements on Sir Francis Drake as a local road does not meet the goal of the project.”

Improvements have already been made on Sir Francis Drake Boulevard, Richman said. There isn’t room to make more changes without significant impacts to the environment because of the shoreline, she added.

Based on preliminary estimates, the project could range from $114 million to $379 million, Richman said.

There is approximately $135 million earmarked for the project from Regional Measure 3 funds. Another $16.5 million is set aside from the Transportation Authority of Marin’s Measure AA halfcent sales tax.

Part of the plan includes replacing the eastbound Interstate 580 overcrossing over Bellam Boulevard and adding bicycle and pedestrian improvements on the boulevard, Richman said.

Councilmember Rachel Kertz asked, “Is there any advantage of doing bike and pedestrian work as an interim or do we have to wait?”

Richman said planners would want to evaluate all aspects of the project as part of one environmental impact review, but they are open to considering phasing portions of the project once that’s done.

Nearly all alternatives would also require land be acquired to construct the connector on or through private land, Richman said.

The project has through 2025 to complete environmental review. The design phase is expected to start in 2026, with any land acquisitions beginning in 2028. Construction would likely happen in 2030.