City of Belmont

Quick Introduction

The Alameda de Las Pulgas Corridor Improvement Project is a multi-agency transportation improvement project that we share with San Carlos, and two School Districts (Sequoia Union High School and San Carlos School District). The project is based on extensive research, community engagement and the Four Corners Traffic Study that took place between 2014 and 2016.  It involves repaving the ADLP between Ralston Avenue and the San Carlos City limits, as well as three new mini-roundabouts, new sidewalks, bike lanes, improved pedestrian crosswalks and a new traffic signal at Carlmont Drive. 

The regional transportation project will make the corridor safer for all modes of travel, less congested during busy commute and school start/end times, and the new design features will shorten travel times in the corridor as well as shortening the lengths of the morning and afternoon peak travel periods. 

Did you know: We are continuing to pursue and apply for state and federal grants to fully fund the project. We’re designing the project with a phased approach if the project cannot be fully funded by the planned start of construction in Summer 2025.

Project Milestones

On July 1, 2022, California Assembly Speaker Pro Tempore Kevin Mullin announced funding support of the project. Read the announcement here. 

On Aug. 23, 2022, project planners welcomed all to a Community Workshop to hear feedback on the current status of the project. 

You can view the presentation here: August 23, 2022 Workshop Presentation.

On Nov. 17, 2022, the project team welcomed all to Community Workshop #2 to share updates on the project.

You can view the presentation here: November 17, 2022 Workshop #2 Presentation

In late 2023, 65% project plans were submitted which can be viewed here: ADLP_65%_Plans_CLEAN

In late 2025, the project was separated into multiple phases to better align with funding constraints and accelerate near-term safety improvements serving the school area. Phase 1 focuses on improvements along Alameda de las Pulgas between El Verano Way and Cranfield Avenue, including multimodal safety enhancements and a new traffic signal at the Alameda de las Pulgas/Carlmont Drive intersection.

On March 12, 2026, the San Carlos School District conducted a Safe Routes to School Workshop for the Mariposa Upper Elementary School, Tierra Linda Middle School, and San Carlos Charter Learning Center campus. The workshop identified the Alameda de las Pulgas Multimodal Safety Project as a priority recommendation to improve student safety, circulation, and multimodal accessibility in the corridor.

The associated walk audit findings can be viewed here: Dartmouth Avenue Area Schools Walk Audit Report

Project Background

Click on the buttons below for additional corridor study information.

FREQUENTLY ASKED QUESTIONS

How was a roundabout chosen for a given intersection along Alameda de las Pulgas?

Historically, well-designed roundabouts that have been implemented around the state have proven to reduce (or in some cases eliminated) queues that existed prior to their installation. Between 2014 and 2016, W-Trans modeled and analyzed the Alameda de las Pulgas corridor with SIDRA software for both 4-way stops and

roundabouts under peak and off-peak volumes as part of the Four Corners Study. Evaluations were completed for each intersection individually and the corridor holistically where roundabouts were shown to perform better in peak and off-peak volumes compared to 4-way stops. Extensive public outreach occurred during the development of the Four Corners Study between 2014 and 2017 to assess traffic safety and operations on Alameda de Las Pulgas. During the process, preferred alternatives were developed and adopted by both Belmont and San Carlos City Councils for the corridor improvements.

Are roundabouts better than traffic signals? Roundabouts historically have a better track record to be more efficient and safer compared to its traffic signal counterpart. For improved safety, necking down and narrowing occurs at the lanes entering/exiting the roundabout to slow down vehicles, improve sight lines and shorten pedestrian crossing distance. Vehicles that get past a crosswalk will yield to any vehicle within the roundabout, meanwhile more pedestrians will be able to cross the street behind yielding vehicles thus improving pedestrian and vehicular safety and circulation. Additionally, vehicles are allowed to yield rather than come to a complete stop to improve traffic circulation and help to reduce delays.

Will a roundabout alleviate traffic congestion during peak (school) hours?The corridor improvements with mini-roundabouts will help to improve existing traffic operations   during the off-peak and it will improve delays during peak hours, as well as reducing the duration of peak demand. 

Will entry to schools be provided with the project?
Coordination with San Carlos School District is ongoing regarding the optional driveway entrance on Alameda de Las Pulgas. The addition of the driveway entrance into Carlmont High School is critical to the project’s success and will benefit the proposed corridor improvements if implemented. 

Can additional crosswalks be provided at roundabouts?
The design provides optimal locations for crosswalk. Additional crosswalks would affect roundabout operations and through traffic, and could diminish safety. 

Can protected crossings such as crossing guards and/or HAWK systems be provided?
Crossing guard programs may be considered under separate projects/programs. Funding for this project must be used for the construction of roadway infrastructure improvements. HAWK or Flashing Beacon (RRFB) systems may adversely affect roundabout operations and will therefore not be included.

Can speed limits be lowered near schools (i.e., add speed humps and signs)?Implementation of standard roundabout designs will reduce vehicle speeds along the corridor. The 25-mph speed limit, when obeyed by drivers and enforced by PD, is an appropriate speed for a school zone and on all residential streets. 

Will sidewalks be widened along the corridor?
The project proposes 6 feet minimum sidewalks where feasible along the corridor that are wider than current city standard sidewalk widths. The project also adds sidewalks where none currently exist along the corridor, thus improving pedestrian safety. 

Will any buffer/barrier be provided between parked cars and bike lane?
Striped buffers are proposed between the travel way and bike lanes as part of the project. 

Will additional Class II bike lanes be provided between Ralston Avenue and Carlmont Drive?
With inadequate right-of-way and physical constraints, it is not feasible to safely add Class II bike lanes within this road segment.

TABLES FROM CORRIDOR STUDY

HANDOUTS

Roundabouts vs Traffic Signals

Mini-Roundabouts Excerpt (W-Trans)

Alameda de las Pulgas_Collision Map

Alameda de las Pulgas_Collision Data

Roundabouts – 1,2,3 Rules (FHWA)

Roundabouts – Safer Choice (FHWA)

Roundabouts – Pedestrians & Bicycles (FHWA)

ADDITIONAL INFORMATION

https://highways.dot.gov/safety/intersection-safety/intersection-types/roundabouts

https://www.iihs.org/topics/roundabouts#safety-benefits

https://wsdot.wa.gov/travel/traffic-safety-methods/roundabouts

Thanks to the hard work and concerted efforts of citizens, city staff, and consultants, the Alameda de las Pulgas/San Carlos Avenue Corridor Study and Transportation Improvements Four Corners Traffic Study was unanimously approved by Belmont City Council as a Corridor Context Sensitive Plan on February 9, 2016. View City Council Documents below.

Staff Report

Resolution

Council Meeting

Four Corners Traffic Study

The working group includes staff and elected members of the Cities of Belmont and City of San Carlos, the Sequoia Union High School District, and the San Carlos School District.

Alameda de Las Pulgas Corridor Improvement Project is a multi-agency regional transportation improvement project involving cities of Belmont, San Carlos, and two School Districts (Sequoia Union High School and San Carlos School District) along the Alameda de Las Pulgas and San Carlos Ave Corridor.  

The project is currently in the design phase (2021-23). BKF is leading the design effort which is being funded by both cities. This calendar year will be a key year for gathering public input to refine the initial design, no construction funding has been secured yet. While initial attempts at securing construction funding have begun, the completion of design by early 2023 will put the cities and school districts in a good position to be very competitive in seeking grant funds in the $5 million plus range to bring the project to fruition.

The project meets numerous mobility, stormwater pollution elimination and GHG emission reduction objectives, including the following:

• Mobility Safety Improvements
• “Safe Route to School” enhancements
• Improves bike/ped safety and circulation and access near housing, shopping, and schools
• Improving all modes of transit through the corridor
• Peak hour congestion relief and GHG reduction by improving traffic flow on Alameda de Las Pulgas and San Carlos Ave
• Installation of green infrastructure to reduce stormwater roadway pollution
• Improved on site and near-site school drop-off and pick-up circulation for Carlmont High School and Tierra Linda Middle School

In the corridor area, Alameda de Las Pulgas and San Carlos Avenue serve as the main thoroughfares for residents heading to retail destinations in San Carlos and Belmont, as well as regional destinations on Highway 101 and Interstate 280. The corridor is also heavily used by commuters from Belmont and San Carlos heading to their employment destinations or the Caltrain stations in each city.

During the school year, the corridor is heavily congested in the area due to traffic accessing Carlmont High School, Immaculate Heart of Mary School, Charles Armstrong School, and Tierra Linda Middle School. In the AM peak hour, southbound queues on Alameda de Las Pulgas extend from Carlmont Drive to 500 feet east of Dartmouth Avenue, while northbound queues extend from Dartmouth Avenue to nearly Carlmont Drive. 

The four agencies have entered into a memorandum of understanding and are working with a qualified Traffic Engineering consultant to conduct a study of this area. The consultant’s scope of work consists of data collection, review and analysis, alternatives/options development and public outreach. Options/alternatives will include: options for traffic (bicycles and cars) circulation; pedestrian circulation; and parking within the public right of way and on both school campuses. Alternatives will also include: consideration of alternative school entrances/exits, traffic control measures for the corridor and side streets; and alternatives for improving transit through the corridor.

February 24, 2022 

Preliminary data collection work began way back in 2014, and the corridor study continued between 2014 and 2016.  

City staff and the consultant team met with the Carlmont High School staff and San Carlos School District officials to evaluate pedestrian, bicycle and vehicular circulation issues through the Alameda de las Pulgas/San Carlos Avenue corridor in the vicinity of these schools.

The same group conducted a walking audit to identify barriers, challenges, and opportunities to improve the safe operation within the corridor. That work provided the basis of the initial design concept which is available on this website.

BKF Engineering came on-board in 2021 to kick off this design effort, and 2022 will be the year when all parties seek public input and refinement of the design concept.

Finalizing this design by 2023 will enable all parties to be in the best position to seek grant funds for construction.