DATE: May 19, 2025
TO: Mayor and Members of the City Council
FROM: Stefan Chatwin, City Manager
San Mateo County Transportation Authority
DEPARTMENT: City Manager
SUBJECT: PRESENTATION BY THE SAN MATEO COUNTY
TRANSPORTATION AUTHORITY REGARDING THE US 101/SR
92 INTERCHANGE DIRECT CONNECTOR PROJECT
RECOMMENDATION
This is an informational item. No action is required.
EXECUTIVE SUMMARY
The purpose of this informational item is to provide an update on the US 101/SR 92 Direct Connector Project, the progress of the environmental review for the project, and consider the San Mateo County Transportation Authority’s (TA) proposed public participation approach.
The proposed project, if approved, would add a new connection between the US 101 Express Lanes and State Route 92 (“Direct Connector”) to improve travel time reliability, encourage carpooling, improve traffic flow, and reduce cut-through traffic on local streets. Drivers using the Direct Connector would be able to remain in the center lanes and use a new elevated median ramp to get from one freeway to the other without having to merge and weave across multiple lanes or cut through local streets.
The new connector would operate as a “managed lane” to encourage more carpooling and to support potential transit service. The current project alternatives would not require the purchase of houses or parks in San Mateo; and at least one of the alternatives would not require any additional land beyond existing Caltrans property.
Additional analysis and Caltrans approval is needed to determine all of the potential project impacts. Potential project impacts will be documented in a Draft Environmental Impact Report (EIR) scheduled for release in Fall 2026.
BACKGROUND
Improvements to the US 101/SR 92 interchange have long been prioritized by San Mateo County voters. The interchange was identified as part of the 1988 Measure A Transportation Expenditure Plan (TEP) and as a “Key Congested Area” in the 2004 Measure A TEP. In 2018, voters throughout the Bay Area continued to prioritize the interchange with the passage of Regional Measure 3 (RM3) that dedicates funding from increased toll bridge revenue to improve the US 101/SR 92 interchange.
In 2016, the TA coordinated a Preliminary Planning Study in partnership with City/County Association of Governments (C/CAG) and the cities of San Mateo and Foster City to evaluate potential solutions for the interchange. Thirteen concepts were evaluated based on performance and city input. The final 2016 Planning Study recommendations were packaged into short-term and long-term improvements. The short-term package advanced as the “Area Improvements” Project which began construction in April 2025 and is scheduled for completion by Summer 2028.
The cities separately advanced the long-term package as the Direct Connector Project and completed the project initiation phase in 2021. This was the first step in the project development process and included high-level conceptual designs to be further evaluated in the subsequent environmental phase. During this step, several long-term solutions from the 2016 Planning Study were eliminated from further consideration due to relatively larger property impacts, lack of local support, and minimal benefits to traffic flow. The remaining long-term solution was the Direct Connector concept.
For subsequent phases, the cities requested that the TA and C/CAG co-sponsor the project and the environmental review due to its regional nature and the level of effort required (Attachment 1). The Direct Connector is currently in the environmental review phase. There are four (4) alternatives being evaluated, as listed below. Preliminary engineering and engineering studies are currently underway to further refine these alternatives. Based on the current alternatives, none would require purchasing houses or parks, and at least one (Alternative 3) would not require any land beyond existing Caltrans property. The design details and traffic analysis/studies will continue to progress as part of the environmental review process.
•No Build Alternative: No Action
•Build Alternative 1: Direct Connector from Westbound SR 92 to the US101 Express Lanes
•Build Alternative 2: Reversible Direct Connector Between the US 101 Express Lanes and SR 92
•Build Alternative 3: Direct Connector from the US 101 Express Lanes to Eastbound SR 92
ANALYSIS
The level of environmental review required for the proposed Direct Connector Project per the California Environmental Quality Act (CEQA) is an EIR based on project complexity and size. The EIR will identify the potential environmental effects of each project alternative regarding various environmental topics such as air quality, noise, right-of-way/property, and water quality. These analyses will be based on preliminary engineering studies that will further detail proposed geometric layouts, structures, drainage, and other design features. As environmental and engineering studies progress, the design team will continue refining the project design to minimize/avoid any potential impacts. This process is a multi-faceted approach designed to ensure that transportation projects are developed in a way that minimizes environmental harm and maximizes benefits for the public. As such, the current project alternatives do not require the purchase of houses or parks in San Mateo and at least one of the alternatives would not require any land beyond the existing Caltrans property but are subject to additional analysis and approval by Caltrans. Further assessment is underway to determine whether there would be potential impacts to some residential yards and/or the area behind rear fences and the freeway soundwall in San Mateo. The public will have the opportunity to review and comment on the complete assessment of all potential effects of the project as part of the circulation of the Draft EIR that is anticipated by Fall 2026.
The Draft EIR as well as public feedback, city input, technical feasibility, and project benefits will inform selection of a preferred alternative in early 2027. Staff will make a recommendation to be considered by the Board of Directors for the TA and C/CAG (Boards). Then, the Project Development Team, comprised of Caltrans and project sponsor staff, will make a recommendation to Caltrans for ultimate approval. The selection of the preferred alternative and completion of the environmental phase is anticipated by Summer 2027. Funding to advance a preferred alternative to the final design and construction phase would be subject to approval from the TA and C/CAG Boards.
To fully fund the project, additional federal and state funding would likely be needed to leverage regional and local funding. The Project Initiation Document estimated the construction cost at approximately $200 million; an updated value will be included in the project report and will be an important part of the discussion when deciding whether the project should continue or not.
Public Participation Approach
Community feedback and city input are key factors in the selection of a preferred alternative. The proposed public participation approach is detailed below and structured in three phases based on key engagement topics and progress with design and environmental studies.
Phase 1: Project/Process Understanding & Early Input
The first phase is focused on establishing a general understanding of the project and process; as well as seeking early input to inform the project design. Since environmental and engineering studies are still in progress during this period, there is limited information available on the project’s viability, costs and benefits. Therefore, outreach topics will focus on the project development and approval processes, as well as the Project’s Purpose & Need. There will also be early opportunities for the public to inform project elements as the preliminary engineering and environmental studies are being developed. These focused topics may include potential future transit service, potential ramp intersection modifications, and potential design features.
Community input will be solicited through the public scoping meeting, “office hours” with community members neighboring the project area, a neighborhood meet & greet, and focused topic discussions. Office hours were offered in April 2025 via mailer to properties along northbound 101 in San Mateo that were previously identified in the prior planning study as potentially impacted. Project team members were also available at an in-person Neighborhood Meet & Greet in May 2025 to gather community input and provide project information. Community members are encouraged to contact the project team at any time with comments/questions via email at [email protected].
Phase 2: Project Benefits & Potential Impacts
Phase 2 will coincide with the completion of the technical analyses and the release of the Draft EIR. Outreach topics will focus on informing the public of potential project benefits and impacts and promoting where to get more information and how to comment on the Draft EIR. Status updates and a preview of the Draft EIR will be presented to the city councils of the cities of San Mateo and Foster City, the C/CAG Board, and the TA Board in Fall 2026. Following the release of the Draft EIR, outreach activities will include the holding of a public hearing, presentations to the Boards, and attendance at community meetings to encourage public review and comment on the Draft EIR.
Phase 3: Preferred Alternative & Next Steps
In Phase 3, a preferred alternative will be selected, and the final EIR will be published.
Project reference materials will be updated to document the final decision. The Boards will collectively decide if the Project should advance to final design, which would include seeking funding for future phases of work.
The Project is currently in Phase 1, and staff are seeking feedback to inform ongoing public participation efforts.
California Environmental Quality Act
Not Applicable
FISCAL IMPACT
There is no fiscal impact associated with receiving this informational report.
CITY COUNCIL VISION, MISSION, AND VALUE/PRIORITY AREA
Facilities and Infrastructure
Smart Planning, Development, and the Local Economy
ATTACHMENTS:
Attachment 1 – Letter from Foster City Public Works Director (dated July 17, 2019) Attachment 2 – Presentation