Northbound US-101 to Eastbound I-580 Direct Connector (Transportation Authority of Marin)

Northbound US-101 to Eastbound I-580 Direct Connector (Transportation Authority of Marin) looking northeast


Project Goals

  • Create a permanent two lane connector from northbound U.S. 101 to eastbound I‐580
  • Construct an extra lane between Bellam Boulevard and the Sir Francis Drake on-ramp to the Richmond-San Rafael Bridge


Current project funding $135,000,000 (Measure AA/Regional Measure 3 funds)
Local funding $16,500,000 (Marin County ½¢ Transportation Sales Tax)


The Transportation Authority of Marin (TAM) has begun planning for proposed project to construct a direct highway connection from northbound US-101 to eastbound I-580 in Marin County. TAM is currently identifying options to study as a part of the environmental analysis. TAM will to evaluate options and work with the community and stakeholders to select a preferred alternative.

This project is a collaborative effort between TAM, the California Department of Transportation (Caltrans), and the cities of San Rafael and Larkspur.  

Currently, drivers who wish to access the Richmond-San Rafael Bridge (I-580) via northbound US-101 have to exit the freeway and travel on East Sir Francis Drake Boulevard or across Bellam Boulevard to the bridge entrance.  Having to drive on local streets causes congestion and traffic delays on northbound US 101 and on local streets, including Sir Francis Drake Boulevard and Bellam Boulevard.

The proposed project will allow vehicles to continue along US-101 northbound onto a new highway connector in San Rafael and merge directly onto I-580 eastbound toward the Richmond-San Rafael Bridge.

Guiding Principles

If the project is eventually built in San Rafael, the new corridor will change traffic patterns, impact local businesses, and change the way residents and businesses in Southeast San Rafael traverse this vital area of the City. So, the City reviewed “guiding principles” to help evaluate the alignment options that the City would ask TAM to pursue during the environmental review process.  These guiding principles include:

  1. Reduction of travel delays and increase transportation choices for all travelers
  2. Support future economic investment and development
  3. Improve the safety of all travelers
  4. Fit in with its setting and be aesthetically pleasing
  5. Minimize impacts on the environment
  6. Design for the future—not the past
  7. Build the project in an efficient, timely way

Frequently asked questions (FAQs)

TAM is a management agency that with towns, cities, transportation agencies, and community groups in Marin to identify and prioritize transportation needs and to distribute local, state and federal funds to address those priorities.

Highways are under the State’s jurisdiction, therefore Caltrans maintains all of California highways, on and off-ramps, as well as, streets underneath the raised highway. This means that even though this project includes San Rafael, TAM is working with Caltrans as the lead agency for the project scope, schedule and management of the contractor. While TAM is giving the City updates on the project, the City is not managing the project.

Project Presentation at July 6, 2021 City Council Meeting

Project contact

Molly Graham | Public Outreach Coordinator

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