US-101/I-580 Multimodal and Local Access Improvement Project (Transportation Authority of Marin)


Project Goals and Objectives

  • Enhance circulation on local streets by separating regional pass-through traffic from local traffic on surface streets and provide reliable travel times for regional and local traffic.
  • Enhance the active transportation network (e.g., bicycle, pedestrian, bus transit) within the project area and improve connectivity to transit hubs in San Rafael, Larkspur, Richmond, and El Cerrito.
  • Enhance bicycle and pedestrian safety on local streets by constructing protected bike lanes and rerouting regional traffic that contribute additional risk and stress to bicyclists, pedestrians, and other vulnerable road users.
  • Improve connectivity between NB US 101 and EB I-580 for regional traffic in and out of Marin County using the Richmond-San Rafael Bridge.
  • Enhance and support economic prosperity in the project area by providing better and more reliable access to current and future businesses.


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  and improve safety and mobility in the Bellam Boulevard Corridor. TAM is currently identifying options to study as a part of the environmental analysis. TAM will evaluate options and work with the community and stakeholders to select a preferred alternative.

This project is a collaborative effort among 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 I-580 and the bridge entrance.  Highway drivers on local streets cause congestion and traffic delays on Sir Francis Drake Boulevard and Bellam Boulevard and on northbound US 101.

The proposed project would 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)

The Transportation Authority of Marin (TAM) plans and funds transportation projects and programs that improve mobility, reduce congestion, and provide a transportation system with more options for those living, working, visiting, and traveling in Marin County.

Highways are under the State’s jurisdiction, therefore Caltrans maintains all of California highways, on- and off-ramps, and lands and 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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