SM 101 Express Lanes Project
The Express Lanes on southbound and northbound U.S. 101 from Whipple Avenue in Redwood City to I-380 in South San Francisco will begin toll equipment testing in November 2022. This testing is an important step needed to ensure that all the tolling equipment is communicating correctly and can accurately charge drivers that choose to access the lanes.
During testing, the Express Lanes be open to HOV 3+ (carpools with 3 or more people) and motorcycles. We anticipate the lanes will be fully operational in early 2023.
The Express Lanes from the San Mateo County/Santa Clara County line to Whipple Avenue in Redwood City opened in early 2022 and are available for use.
Toll Equipment Testing
Construction of the Express Lanes from Whipple Avenue in Redwood City to I-380 in South San Francisco is nearly complete, and toll equipment testing will begin as early as the last week of October. During testing, the lanes will be open to HOV 3+ and motorcycles only 5 AM – 8 PM, Monday through Friday. FasTrak® is required.
The new Express Lanes will open to HOV 3+ and motorcycle traffic after the following opening sequence is complete:
- The “UNDER CONSTRUCTION” banners are be replaced by “TOLL TESTING” banners.
- The destinations are covered by temporary “HOV 3+ ONLY” signs (as shown in the picture below).
- The temporary orange reflective barriers that are currently blocking the new Express Lanes are removed. Approximately 3 miles of barrier can be removed per night until the entire lane is open.
Express Lane Variable Toll Message Sign During Testing
The southbound lane will open first, followed by the northbound lane. Depending on weather, the southbound lane will be fully open for HOV 3+ and motorcycle traffic by the last week of October*, and the northbound lane will be fully open for HOV 3+ and motorcycle traffic by the first week of November*. Click here to see an animation of the opening sequence.
*These dates are estimates. Construction activities are subject to change without notice.
Using the New Express Lanes During Toll Equipment Testing
The project team aims to increase the number of people moved through the corridor and encourage carpooling and transit use. In addition, the project team hopes to use the toll equipment testing period to help all drivers on the corridor become familiar with the operations of the new Express Lanes and avoid confusion. Therefore, during the toll equipment testing period, the new lanes will be open to HOV 3+ (carpools with 3 or more people) and motorcycles (along with any other vehicle exempt from tolls by Section 7 of the ordinance) during their normal operating hours (5 AM to 8 PM Monday – Friday). The Express Lanes will be open to all vehicles during all other times.
The Express Lanes are anticipated to be fully operational in early 2023. At that point, the “TOLL TESTING” banners will be removed, and tolls will be visible on the Express Lanes Variable Toll Message Signs (VTMS). Anyone wishing to use the lanes will need a valid FasTrak®. To learn more about using the Express Lanes in San Mateo County, visit 101expresslanes.org.
The San Mateo 101 Express Lanes Project is a multi-year, multi-agency project initiated to reduce traffic congestion and encourage carpooling and transit use on U.S. 101 in San Mateo County. The Project is creating 22 miles of Express Lanes in both directions on U.S.101 from the San Mateo County/Santa Clara County line to I-380 in South San Francisco. The San Mateo 101 Express Lanes will seamlessly connect to the Express Lanes in Santa Clara County.
The Express Lanes are designed to maintain speeds of 45 miles per hour or greater, resulting in reduced and more reliable travel times. To learn more about how the Express Lanes operate, see the image below and check out the Frequently Asked Questions and Project videos series. Please also visit 101expresslanes.org for more information on how to use the Express Lanes.
What is an Express Lane?
- Buses and 3+ carpools drive for free
- Other drivers can choose to pay
- Electronic toll collection
- Dynamic tolls (congestion pricing) keep lane free flowing
Key Project Benefits
- Reduce congestion in the corridor
- Increase person throughput (the number of people moved)
- Encourage carpooling and transit use
- Improve travel time and reliability for Express Lane users
- Use modern technology to manage traffic
- Make upgrades to pavement and lane striping
Construction of the San Mateo 101 Express Lanes is being completed in two phases:
Phase One – San Mateo County/Santa Clara County line to Whipple Ave: Phase One construction began in March 2019. During this phase, the carpool lanes from the San Mateo County/Santa Clara County line to Whipple Ave in Redwood City were converted into Express Lanes. The lanes opened in February 2022.
Phase Two – Whipple Ave to I-380: Phase Two construction began in February 2020. During Phase Two, new Express Lanes from Whipple Ave to I-380 in South San Francisco are being constructed. Express Lanes are anticipated to fully open to HOV 3+ and motorcycle traffic by the first week of November and fully operational for all who wish to access the lanes in early 2023.
Construction activities are nearly complete, but temporary nighttime freeway lane and ramp closures may still be required to finalize all express lane equipment installation and connection.
Lane and Ramp Closures
Lane closures are implemented to facilitate work on the freeway lanes and ramps for the safety of crews and nearby travelers during construction activities. Freeway lane closures may occur on northbound and southbound U.S. 101 lanes from 9:00 PM to 5:30 AM, Sunday night to Saturday morning. Travelers can see real-time traffic conditions from changeable message signs placed in the construction zone. The Smart Traffic System was implemented during construction to provide up to date information, improve safety, and reduce congestion.
Ramp closures may occur on northbound and southbound U.S. 101 from Sunday night to Saturday morning from approximately 8:00 PM to 6:00 AM. Consecutive interchanges for northbound and southbound ramps will not be closed at the same time. Ramp closure information will be displayed on changeable message signs within the construction zone and detour signs will be posted.
For questions during construction, or to request a presentation from a project representative, contact the Caltrans Public Information Officer:
Alejandro Lopez at (510) 385-6856 or email email@example.com.
Join our mailing list by emailing firstname.lastname@example.org.
The management and operation of the San Mateo 101 Express Lanes is governed by the San Mateo County Express Lanes Joint Powers Authority (SMCEL-JPA), a six-member joint powers authority consisting of three San Mateo County Transportation Authority (SMCTA) Board members and three City/County Association of Governments of San Mateo County (C/CAG) Board members. Visit 101ExpressLanes.org to learn about San Mateo 101 Express Lanes policy and governance.