State moving forward with bike lanes on Tiburon Boulevard

Belveron resident and cyclist Kathy McLeod shows current conditions while advocating for new bike lanes during the public-comment period of a special June 4 Town Council meeting discussing Caltrans’ preventive-maintenance project on Tiburon Boulevard. Behind her at right is Greg Moore of Greenwood Beach Road, who also advocated for the lanes, while at front right are Tiburon Peninsula Traffic Alliance Chair Bob McCaskill and Belvedere Vice Mayor Sally Wilkinson, also on the local traffic agency, who say the lanes pose safety issues, would remove school-bus stops and cause further traffic congestion. (Francisco Martinez / The Ark)

Caltrans officials say a controversial bike-lane project on Tiburon Boulevard must proceed as planned in early 2026, citing funding deadlines and concerns that winter storms could further damage the deteriorating roadway.

While rumors had swirled ahead of the Tiburon Town Council’s special June 4 meeting that Caltrans had already decided to delay the project for two years, the state agency instead announced a two-phase approach: implementing basic improvements including bike lanes next year, followed by enhanced safety features in a second phase beginning in fiscal year 2027-2028.

The 4.6-mile project spans state-owned Highway 131 from outside Mill Valley to Tiburon Boulevard’s intersection with Main Street. Caltrans has $12.7 million in construction funding that officials said could be lost if the project is delayed.

“What we have right now is very limited, we understand that,” said Wajahat Nyaz, Caltrans’ Bay Area district deputy director for project design. A second phase will feature community collaboration “to find these kinds of solutions that we can fund and that can also improve safety.”

Project details and timeline

The project primarily involves repaving the road due to deteriorating conditions. But Caltrans’ Complete Streets directive requires the agency to consider improvements for pedestrians and cyclists alongside drivers.

A combination of separated, mixed-use Class-1 paths, painted Class-2 bike lanes and protected Class-4 bikeways would be added from outside Mill Valley to Trestle Glen Boulevard on the north side and to Blackie’s Pasture on the south side.

Caltrans’ project-initiation report of 2019 for funding in 2020 included painted lanes as a “top-tier priority,” with an option for protected bikeways from Highway 101 to Trestle Glen and Blackie’s. The report specifically cites recommendations from Tiburon’s 2012 Bay Trail gap study and 2016 bicycle-and-pedestrian master-plan update, along with Marin and Caltrans master plans of 2018. Later, Tiburon in 2023 approved recommendations for protected bikeways as part of its Create Tiburon 2040 general plan.

The lanes primarily became protected, with physical barriers separating cyclists from traffic, after further discussion with advocacy groups including Marin Safe Routes to Schools and were part of the draft initial study released in 2023.

Under plans advocated by Safe Routes, Caltrans and historically by the town, the addition of bike lanes on Tiburon Boulevard intends to increase safety for faster riders. That work was to complement improved signs and pavement markings directing pedestrians and slower riders, including schoolchildren, to Greenwood Cove Road and Greenwood Beach Drive, the contiguous roads parallel to Tiburon Boulevard that link directly with the Old Rail Trail.

Caltrans spokesperson Matt O’Donnell said the agency considered various bikeway types on Tiburon Boulevard “to identify the most practical and appropriate facility based on site-specific conditions,” adding that the segments of protected bikeways “is consistent with our Caltrans District 4 Bike Plan and Caltrans contextual design guidance for Complete Streets.”

Phase one would begin as early as spring, adding bike lanes, narrowing traffic lanes and modifying bus stops, traffic signals and crosswalks. The project would also install fiber-optic infrastructure to connect intelligent traffic signals, downtown government buildings and businesses. Mayor Holli Thier has made the broadband infrastructure a priority, with plans to eventually link Tiburon neighborhoods.

Phase two would incorporate community feedback and add safety improvements including bump-out curbs extending into the road, accessibility improvements at bus stops, some protected intersections and fully converting one segment of painted lanes into protected bikeways.

A Google Earth map provided by Caltrans and enhanced by The Ark shows how bike paths planned for the Tiburon Boulevard rehabilitation project will integrate with existing paths. Some residents and public agencies have cited concerns over safety, traffic congestion and bus access, but Caltrans announced it will continue with the project in two phases, the first to incorporate the lanes as planned next year and the second in fiscal 2027-2028 to address community concerns. (via Caltrans)

Community divided over safety concerns

More than 60 people packed Town Hall chambers for the special meeting with the council and Southern Marin Supervisor Stephanie Moulton-Peters, with overflow seating in the break room, additional viewers in an upstairs conference room and over 35 people watching on Zoom.

Local agencies including Belvedere, the Reed Union School District, Marin Transit and the Tiburon Peninsula Traffic Agency have raised concerns about safety, traffic congestion, emergency-response impacts, crosswalk designs and school-bus service disruptions, particularly along the stretch from Blackfield Drive to Trestle Glen Boulevard.

Meanwhile, bicycle advocacy group WTB-TAM said the project didn’t go far enough, calling for bike infrastructure improvements including pushing back bike lanes at intersections and creating bend-outs that route lanes behind bus stops.

Nyaz acknowledged that “one of the key nuances” with the proposed bike lanes involves intersections and bus stops, where protected bikeways become unprotected lanes, allowing vehicles to enter the space.

“There are lots of intersections, there are lots of bus stops,” Nyaz said. “So, there will be quite a few zones where we are mixing.”

School bus service concerns

One of the most contentious issues involves four school-bus stops that local officials have said could go out of service because First Student, the bus provider, indicated it would not stop in bike lanes by policy. However, last week a First Student spokesperson disputed that interpretation.

Bob McCaskill, who chairs the Tiburon Peninsula Traffic Alliance, said stops near Greenwood Cove Drive, Cecilia Way, Blackie’s Pasture and Jefferson Drive would be affected. He reiterated concerns shared by fellow traffic-board members Belvedere Councilmember Vice Mayor Sally Wilkinson and Reed Union board trustees Shelby Pasarell Tsai and Liz Webb.

“Kids won’t be able to get to school anymore because our bus provider has said they will not stop in bike lanes,” Wilkinson said.

But First Student spokeswoman Jen Biddinger told The Ark that California law “allows school buses to enter and block bike lanes to load or unload students” and, when provided with Caltrans diagrams outlining potential bus-bike infrastructure at Tiburon Boulevard near Cecilia Way to serve Marin Transit, she said “it appears the bus could enter the painted bike lane to load or unload students.”

She added that “all stops would need to be evaluated with the safety of students and the state law in mind.”

Addressing that discrepancy, McCaskill said his agency’s response has ultimately “relied on the advice of the transit professionals at Marin Transit and First Student who have concluded that the stops between Trestle Glen and Blackfield would be unsafe if the proposed bike lanes were added.”

Residents split on bike lane location

Over 40 people spoke in person and online, in addition to 79 written correspondences received ahead of the meeting.

Tiburon resident Winnie Anderluh opposed the proposed bike lanes between Trestle Glen Boulevard and Blackfield Drive, suggesting Greenwood Beach Road as “a safer, more beautiful and already established bike route.”

“Taking an eraser to that section of bike lane on your plans cannot set this project back two years, and it should actually save Caltrans some money,” Anderluh said.

Anderluh is among the residents and groups concerned that kids will be tempted to continue along the north side of Tiburon Boulevard when biking to school. One segment between Trestle Glen and Reed Ranch Road is unprotected alongside outbound drivers gaining downhill speed through the curve. Caltrans officials said that piece would be protected in phase two.

Bel Aire resident and cyclist Tom Knauer said creating a bike lane on the boulevard won’t draw widespread usage, saying “neither the kids, nor the recreational cyclists nor my commuter friends will be using that.” He also supported Greenwood Beach Road as the existing bike path.

But Greenwood Beach Road resident Greg Moore spoke and wrote in support of the boulevard bike lanes on behalf of his neighborhood, which has long advocated for moving faster cyclists off their narrow street with parked cars, blind corners and hills.

“We are not asking that Greenwood Beach Road eliminate bicycle, pedestrian or automobile use, even though those impacts are real and mainly negative for our neighborhood,” Moore said. “We are simply asking for a safer solution for all, by moving higher-speed bicyclists to another route: a safe Class-4 bikeway on Tiburon Boulevard.”

Greenwood Beach residents have long rebuffed suggestions of adding a bike path or painted bike lanes to their street, and in previous studies has town agreed. Officials noted in the Bay Trail and cycling master-plan studies that even after removing parking on one side, the roadway is just 16 to 19 feet for two-way traffic, while widening the road to accommodate paths or bike lanes would require moving a retaining wall, storm drains, utilities and wetlands at an estimated cost of $3 million in 2012 dollars.

Instead, Tiburon has upgraded signs and pavement markings on Greenwood as recommended under its bike-and-pedestrian master plan.

Meanwhile, Belveron resident Nathan Spindel said he supported the bike lanes for his family of five cyclists between ages 5 and 79.

“The proposed separated bikeways would provide the protection and peace of mind necessary for cyclists of all ages and abilities to safely navigate this area,” he wrote.

Sketches shown by Caltrans in its presentation for the Tiburon Boulevard rehabilitation project show, at top, how painted Class-2 bike lanes would be added to outbound Tiburon Boulevard near the bus stop at Cecilia Way before turning into protected Class-4 bikeways in the background. Buses will have to stop in the lane to unload passengers at the curb. A concept to improve safety and accessibility that could be implemented in the second phase of the project would create a bend-out that routes cyclists behind the bus stop island that has a short pedestrian bridge to the sidewalk. (via Caltrans)

Usage data and traffic concerns

A study commissioned by Tiburon found that 2,000 cars use the road during peak weekday commutes. A 2022 report by the Transportation Authority of Marin found that two dozen bikes use the road during this time, increasing to 109 bikes daily for weekdays and 263 bikes daily on weekends.

Councilmember Isaac Nikfar expressed reservations about Caltrans’ plans to narrow vehicle lanes on Tiburon Boulevard to incorporate the protected bikeways, saying that “shrinking lanes, adding bikes, decreasing speed limits aren’t going to have a positive impact on traffic.”

“When it already takes 40 to 50 minutes to go less than four miles, this is something that needs to be part of that process,” Nikfar said. While the road needs repaving, he said you can’t “sacrifice people that want to leave downtown and get to (Highway) 101 for recreation.”

Additional improvements possible

One newer addition could be broadband infrastructure that Tiburon has been working on separately since 2021. That project would run conduit and fiber-optic cable from Highway 101 to downtown Tiburon, including connections to traffic signal control boxes at intersections.

Town officials have said the system could eventually serve as a trunk line for townwide broadband, while on the short term it could help with smart traffic signals and benefit Town Hall, the Tiburon Fire Protection District, the Tiburon Police Department, Reed Union School District schools, the Belvedere-Tiburon Library and downtown businesses — even if the network doesn’t get extended out into neighborhoods.

Agency officials indicated openness to incorporating the project, though more funding would be needed to bring the infrastructure down the boulevard and connect neighborhoods to the conduit.

Town Manager Greg Chanis said after the meeting that the agency and town were scheduled to meet this week to discuss future steps. He said the town appreciates “their willingness to integrate the town’s broadband project into their design and look forward to continue working with Caltrans staff in making that a reality.”

Caltrans program and project management director Doanh Nguyen said the agency was open to working on a task force that is representative of Tiburon Peninsula neighborhoods with both elected officials and appointed representatives before pursuing second-phase funding.

“We need to have to be on the same page on what that’s going to be before we go and try to secure or pursue that funding,” Nguyen said. “And we’re committed to do that.”

O’Donnell said calls to remove bike lanes are difficult because of the Complete Streets directive, as “these elements may only be removed if a compelling safety concern is identified, or they may be postponed if significant delivery issues arise.” He said the agency will coordinate with the traffic alliance, school district and First Student “to address and/or mitigate the concerns” with bus stops.

Thier called the workshop “a new beginning,” while Nguyen said the agency needed to balance community needs with resources and time frames.

“We hear you,” Nguyen said. “We’re committed to really talk about the needs and really tackle the challenge together.”

Reach Tiburon reporter Francisco Martinez at 415-944-4634.