New carpool lane on I-680, California, opens a year ahead of schedule


The Contra Costa Transportation Authority (CCTA), the San Francisco Bay area’s Metropolitan Transportation Commission (MTC) and project partners have announced the opening of eleven miles of new carpool lane capacity to motorists on southbound I-680 (SB I-680) between Treat Boulevard and Rudgear Road, California, a year ahead of schedule.

Part of the Interstate 680 Southbound Express Lane Project, this new segment creates a 25-mile continuous carpool lane on SB I- 680 between Martinez and San Ramon.

This project broke ground in October 2018 and was originally anticipated to open to traffic in late
2021. Earlier this year the Contra Costa Transportation Authority adopted an accelerated and ambitious project schedule, enabling the lane to open to the public as a high occupancy vehicle (HOV) 2+ carpool lane while the Metropolitan Transportation Commission continues to install and test the tolling equipment.

The new lane provides more reliable travel for transit, carpools, and vanpools on SB I-680 and represents the culmination of a highly successful collaborative multi-agency effort.

“The voters of Contra Costa County have shown that they value better transportation options and congestion relief on the I-680 corridor. We are thrilled to be delivering this new carpool lane on-budget and ahead of schedule, and we’re very grateful to project neighbours and the motoring public for their patience as we completed this project in record time,” says CCTA board chair Julie Pierce.

“MTC’s successful partnership with CCTA has closed a significant gap in the Bay Area’s HOV lane network. Using our existing highways to move more people with express lanes and HOV lanes is critical to future Bay Area mobility” said MTC Commissioner Amy Worth.

Lane Operations
The new SB I-680 HOV 2+ carpool lane will operate from 5am to 8pm, Monday – Friday. During these times, only 2+ person carpools and eligible clean air vehicles can use the far-left lane from Marina

Vista Avenue to Rudgear Road. FasTrak signs are in place on this lane while toll testing occurs to prepare for an early 2021 express lane opening. Until then, FasTrak is not required north of Rudgear Road. Once tolling begins in early 2021, all drivers will be required to have FasTrak to use the express lane. Solo drivers will have the choice to pay tolls to use the lanes.

The new lane is buffered from State Route 242 to Treat Boulevard and from Rudgear Road to Stone Valley Road. Buffers are double white lines between the far-left lane and the next general-purpose lane that indicate where it is safe to merge into or out of the far-left lane. Crossing the double white lines of the buffered zones is a violation of the California Vehicle Code, and drivers who cross double white lines could be subject to fines and may get one point assessed on their driving record as well.

Drivers may need to exit the lane early to access highway exits that occur along the buffered portions of SB I-680. New median barrier signs have been installed to explain where to exit the far-left lane to access highway exits.

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About Author


Tom has edited Traffic Technology International (TTi) magazine and its Traffic Technology Today website since May 2014. During his time at the title, he has interviewed some of the top transportation chiefs at public agencies around the world as well as CEOs of leading multinationals and ground-breaking start-ups. Tom's earlier career saw him working on some the UK's leading consumer magazine titles. He has a law degree from the London School of Economics (LSE).