New Ramp Metering Activation Scheduled to Begin November 4, 2025, at Three On-ramp Locations of the Balfour Rd interchange in Contra Costa County

Schedule: Mondays through Fridays
2 P.M. to 8 P.M. for the eastbound direction
5 A.M. to 10 A.M. for the westbound direction

Contra Costa County - Caltrans is set to Activate New Ramp Meters at Balfour Road Interchange in Brentwood on November 4, 2025. Caltrans has operated ramp meters along California State Route 4 (SR-4) since the mid-2010s, and operations along the corridor continue to expand and improve. As part of these improvements, the Balfour Road intersection in Brentwood was recently upgraded to a freeway interchange, with new ramp meters installed on all on-ramps. Ramp metering improves safety by reducing merging and weaving collisions and enhances corridor efficiency by improving traffic flow and reliability for commuters.

The following three ramp meters at the Balfour Road interchange will be activated:

• Eastbound SR-4: Balfour Road loop on-ramp
• Westbound SR-4: Balfour Road loop on-ramp
• Westbound SR-4: Balfour Road diagonal on-ramp

Ramp metering hours at these locations will match the existing schedule of other metered ramps on the SR-4 corridor:

• Eastbound: Monday-Friday, 2:00 PM to 8:00 PM
• Westbound: Monday-Friday, 5:00 AM to 10:00 AM

As funding becomes available, additional ramp meters will be installed in both directions of SR-4. Caltrans is also working with the Metropolitan Transportation Commission (MTC) and local transportation partners to upgrade to Adaptive Ramp Metering (ARM). ARM uses real-time traffic data to adjust metering rates based on current traffic conditions, helping reduce congestion more effectively.

For questions, call the Caltrans Ramp-Metering Activation Hotline at (510) 286-4531.

For 24/7 traffic updates, please visit 511.org: https://x.com/511SFBay For real-time information, visit Caltrans QuickMap: https://quickmap.dot.ca.gov Follow us on X: https://x.com/CaltransD4 Or call 1-800-472-7623, 1-800-427-ROAD for state highway conditions statewide.