Northbound US 101 to Eastbound I-580 Direct Connector

TAM approved four alternative concepts, plus a no-build alternative, to study further in the environmental review phase. These four alternatives were selected from a list of nine initial alternatives.

Each alternative would provide a direct freeway-to-freeway connector between northbound US 101 and eastbound I-580 toward the Richmond-San Rafael Bridge.

The following alternative concepts are under consideration:

Alternative 2, Simms Street

Drivers would exit US 101 northbound between the top of Cal Park Hill and the Bellam Boulevard off-ramp. The connector would be an elevated structure that crosses Andersen Drive and follows the alignment of Simms Street before merging with I-580 eastbound.

Alternative 3A

Drivers would exit US 101 northbound near Bellam Boulevard and merge onto I-580 eastbound on a connector that crosses over the existing off-ramp.

Alternative 3B Modified

Drivers would exit US 101 northbound on a separate lane near Bellam Boulevard and merge onto I-580. The off-ramp from eastbound I-580 to Bellam Boulevard would be replaced with a new, separated off-ramp.

Alternative 6, Andersen Mid-Way

Drivers would exit US 101 northbound between the top of Cal Park Hill and the Bellam Boulevard off-ramp. The connector would be an elevated structure that crosses over Jacoby Street, Andersen Drive, and the Golden Gate Bridge Highway & Transportation District bus yard before merging with I-580 eastbound.

Each of the proposed alternatives, except the no-build alternative, would also include the following improvements:

• A new eastbound auxiliary lane on I-580 from the new connector merge point to the Richmond-San Rafael Bridge.
• Replacement of the eastbound I-580 bridge over Bellam Boulevard with a single-span bridge (removing the columns beneath the bridge).
• Traffic, pedestrian, and bicycle improvements on Bellam Boulevard.
• Ramp metering of the Sir Francis Drake Blvd on-ramp and signal timing on Sir Francis Drake Boulevard between US 101 and I-580.

TAM did an extensive evaluation of potential alternatives in Larkspur, including a hillside option, an elevated structure over Sir Francis Drake, and options to widen Sir Francis Drake in one or both directions. Due to potential construction, environmental, and visual impacts along the waterfront, including impacts to the Bay, ferry, and SMART transit access, those alternatives were eliminated from further consideration. In addition, an on-street Sir Francis Drake option does not achieve the project goal of separating local and regional traffic. Obtaining the necessary regulatory approvals would be challenging for several of these options.

Larkspur Landing is one of Marin’s multimodal transit hubs. Redirecting regional traffic off Sir Francis Drake will reduce congestion on Sir Francis Drake Boulevard and improve access to the various transit connections and therefore improve connectivity for all residents of the county.

In 2018, TAM completed significant improvements to facilitate better access for cars and cyclists to the Richmond-San Rafael Bridge from Marin County, increase local access to adjacent businesses and communities, and provide safe connections for bicycles and pedestrians. These improvements included widening East Sir Francis Drake Boulevard and relocating the eastbound lane drop to reduce congestion and extending the turn pocket on East Sir Francis Drake Boulevard turning onto Larkspur Landing Circle East to allow more cars to queue. (See #7)

Yes, local traffic will still be able to access I-580 from Sir Francis Drake Boulevard and Bellam Boulevard. In addition, the local arterial signals and the freeway ramp meters will be re-timed and coordinated to encourage the regional traffic to use the new connector and allow the local traffic to continue to use the local arterials.

The goal of the Marin 101-580 Connector project is to create a freeway-to-freeway connector that provides a travel time advantage for the regional traffic to stay on the connector and off local streets.

During the environmental review process, the project team will evaluate current and future traffic movements and the travel times for both local and regional traffic. The traffic analysis will show travel times to the Richmond-San Rafael Bridge for each direct connector alternative.

Approximately 85% of the traffic on the Richmond-San Rafael bridge is going to or from destinations within Marin County.

Less than 5% of the Richmond-San Rafael Bridge traffic is going through Marin County to and from the Golden Gate Bridge and San Francisco.

About 10% of the Richmond-San Rafael Bridge traffic is going to and from Sonoma County.

During the afternoon commute (3:00 to 7:00 p.m.), pre-COVID, approximately 5,300 vehicles used Sir Francis Drake to access the Richmond-San Rafael Bridge. During the same commute time, approximately 3,500 vehicles exited from northbound US 101 to Bellam Boulevard. Of these vehicles, approximately 12% continued across Bellam to the Richmond-San Rafael Bridge.

In the last few years, TAM funded improvements on Sir Francis Drake to reduce congestion by adding additional lanes and improving signal timing. Today, as a result of these reduced travel times, almost all traffic from northbound US 101 to the bridge is now taking Sir Francis Drake. Unfortunately, future traffic growth will increase congestion on Sir Francis Drake and further traffic improvements are not feasible. Therefore, future traffic will opt for the Bellam off-ramp, increasing congestion there. Traffic modeling for future conditions shows that the travel time for vehicles on northbound US 101 from Tamalpais Boulevard in Corte Madera to Bellam Boulevard will double, from 13 minutes to 25 minutes in 2040, primarily due to congestion on the Bellam off-ramp.

The most effective way to eliminate the increase in travel time for drivers exiting to Bellam is to separate the regional traffic from the local traffic with a direct connector. The planned traffic analysis will consider traffic volumes and travel times, including future land uses identified in city and county general plans and specific development proposals known at the time.

Recently, TAM funded projects to widen Sir Francis Drake Boulevard in Larkspur and improve signal timing. These improvements, along with the addition of a third lane on the Richmond-San Rafael Bridge, made a significant difference in travel times to the bridge. Unfortunately, there is limited room to widen the local route on Sir Francis Drake without impacting the Bay. Constructing a freeway-to-freeway connector here would require constructing a bridge over or a tunnel under the two Larkspur Landing Circle intersections. This is not possible in this corridor due to the configuration of the local streets, conflict with the existing north-south greenway pedestrian overcrossing, ferry access, proximity to the shoreline, and other environmental constraints.

TAM is funding a near-term project to widen the off-ramp from northbound US 101 to Bellam Boulevard. TAM expects this project to be approved and constructed by the end of 2024.

More substantial changes to traffic circulation and freeway on- and off-ramps at Bellam would require an environmental review before approval. The plan for the Marin 101-580 Connector project has always been to look at Bellam Boulevard improvements along with the direct connector structure and complete environmental clearance on all elements at once. That approval process is likely to take two to four years, at which point TAM could consider project sequencing to construct Bellam improvements first, pending availability of funding.

In the meantime, TAM continues to support and fund local improvements such as the sidewalk improvements along Bellam Boulevard, Francisco Boulevard East (2009), and widening the Bellam off-ramp (coming soon).

There are several intersecting challenges around Bellam Boulevard, including:

• Close spacing of the traffic signals, which limits the storage capacity for stopped traffic and causes congestion at the Bellam Boulevard interchange and on Francisco Boulevard East.
• Intersections with multiple legs that allow all turn movements, which cause delays for all approaches because of the lengthy signal cycles required to allow time for all movements.
• Long crossings and limited space for pedestrians and bicycles, which increase potential conflicts for these users.
• Multiple driveways and the center turning lane interrupt traffic flow.
• Bridge columns under the eastbound I-580 undercrossing (this bridge would be replaced as part of the connector project, opening space for sidewalks and bicycle lanes).
• Limited access and egress to the Canal, Spinnaker, and Baypoint neighborhoods.

Planning for the Marin 101-580 Connector will help improve these conditions but is unlikely to completely address them. Further study of traffic circulation in and out of East San Rafael will need to be addressed in future planning studies such as the planned City of San Rafael’s Priority Development Area, which is awaiting funding (see #13).

As currently conceived, the direct connector project will include improvements along Bellam Boulevard regardless of which connector alternative is selected. TAM is considering the following improvements:

• Replacing the eastbound Bellam Boulevard undercrossing structure, which would provide more width for bike and pedestrian safety improvements.
• Improving traffic circulation and turn movement along the Bellam corridor and ramps.
• Increasing spacing and timing of the signals.
• Consolidating driveways.

During the environmental review, beginning in 2023, there will be extensive community engagement to discuss community priorities and feasibility of improvements.

TAM acknowledges the complex local circulation challenges in East San Rafael affect access, egress, and congestion. The Marin 101-580 Connector project is not intended to solve all issues. Continued coordination with the City of San Rafael and other organizations will be important to address the broader circulation challenges in East San Rafael.

TAM will continue to explore transportation solutions throughout the county, including cooperation with local transportation studies, such as in East San Rafael. The City of San Rafael is taking the lead on several planning activities. For example, the City of San Rafael is conducting a community-based transportation plan focused on East San Rafael. Additionally, the East San Rafael area has been identified as a Priority Development Area for the region, making it eligible for regional grants to conduct land use planning and transportation studies. TAM will assist the City of San Rafael in pursuing grant funds to conduct those studies and continue to look at transportation challenges and solutions as part of those studies.

Both the cities of San Rafael and Larkspur have adopted guiding principles for the project to help direct their decision making. During the environmental review and decision-making process, TAM and Caltrans will continue to consider input from all the affected cities, the county, and the community. The cities of San Rafael and Larkspur’s guiding principles are an important part of the evaluation and continued community discussion around the Marin 101-580 Connector alternatives.

These analyses and other topic areas are important parts of the environmental review process, which TAM expects to initiate in 2023 and complete within two years. The traffic analysis will consider both local and regional traffic movements in Larkspur and San Rafael.

TAM is committed to equity and includes it as a guiding principle in its 2017 Vision Plan with a goal of maximum mobility for all people.

Many community organizations and project stakeholders have expressed concern about equity and how the project will address it. In response, TAM intends to implement an outreach and education plan that will begin in 2023, in parallel with the start of the environmental phase.

The engagement approach is a community-centered model to create opportunities for effective, authentic, meaningful, and sustained partnership with communities in the project area. For example, relative to other stakeholder groups, communities in and around the Canal neighborhood require greater support. The proposed community engagement plan will provide an opportunity to invest in community participation more strategically while being responsive to the context and the barriers to engagement.

TAM intends to expand community engagement throughout the project area to ensure that all community members are included in the discussions of connector alternatives and proposed improvements to Bellam Boulevard.

Although more people are working from home, recent traffic numbers show single-driver cars and other vehicles are back to prepandemic levels. TAM continues to evaluate traffic patterns and will support efforts to explore transportation solutions throughout Marin.

Transit is an important aspect of the overall transportation system. TAM continually evaluates and funds transit improvements. Specifically, TAM is exploring means to increase transit links between the East Bay and Marin in collaboration with regional transit providers such as Golden Gate Transit. TAM has a commute assistance program to incentivize commuters to take public transportation as an alternative to driving. Moreover, the project does not preclude future implementation of transit priorities such as carpool/bus-only lanes and bus priority signals.

TAM is working to reduce bottlenecks and backups on eastbound I-580 as it approaches the Richmond-San Rafael Bridge. In collaboration with the Metropolitan Transportation Commission (MTC), Caltrans, and Contra Costa Transportation Authority (CCTA), a third lane has been opened on the bridge to help alleviate heavy traffic. The third lane now extends from the existing I-580 on-ramp from East Sir Francis Drake Boulevard to the bridge.

As part of the new Marin 101-580 Connector project, a new lane will be built along eastbound I-580 from the new connector entry point to the existing on-ramp from East Sir Francis Drake Boulevard. This auxiliary lane will allow drivers to use three lanes from the new connector all the way onto the bridge and into Richmond.

TAM’s expenditure plan for Marin County includes investments in transit and other alternative transportation. The planned Bellam Boulevard improvements are intended to meet the needs of multiple modes of transportation, not just cars.

The California Department of Transportation (Caltrans), a state agency, owns all the lands under the freeway structures, and where possible and safe, Caltrans reuses the land productively, as in the case of the parking lot under US 101 in downtown San Rafael. In other cases, Caltrans secures the land to prevent public access.

TAM is planning a robust community engagement process during the environmental review phase. Topics will include issues such as biology, air quality, traffic analysis, cultural resources, land use and planning, environmental justice, and human impacts. There will be extensive community engagement, and the feedback gathered could be incorporated into this project.

The planning effort will also include work in the Canal neighborhood and other parts of the project area to build the capacity for local residents to participate and engage thoroughly and constructively in transportation planning for East San Rafael.

TAM expects to initiate the environmental review process in 2023, and to continue community engagement during the process with the goal of deciding on a preferred alternative by the end of 2025.

Following the selection of a preferred alternative, design, land acquisition, and construction are expected to take approximately seven years.