Caltrans District 4 Contra Costa County Newsletter

Contra Costa County Newsletter Banner 2025.

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Welcome to the Caltrans District 4 Contra Costa County Newsletter!

This newsletter is here to keep you informed about current and upcoming Caltrans projects in your county and neighboring areas.

Contra Costa County saw several projects underway. While some have been successfully completed, others are still in progress. Our aim is to ensure you stay informed and prepared, helping you navigate through reduced lanes, closed on- and off-ramps, and extended freeway closures with ease.

Connecting Communities Contra Costa County is the Heart of the Bay Area’s Transportation Network. As our community continues to grow, Caltrans remains committed to keeping the Bay Area moving.

Caltrans Safety Sam Mascot

Safety First: Slow for the Cone Zone
Our employees are our greatest asset, and safety is our top priority. As roadway improvements continue, please remember to "Slow for the Cone Zone." Your caution helps protect the hardworking crews who are building a better, safer transportation future for all.

🏗️ Here’s what you need to know?

CURRENT AND FUTURE CONSTRUCTION PROJECTS IN CONTRA COSTA COUNTY


CURRENT PROJECTS

🚧 I-80 Median Barrier, Paving & Lighting Safety Project

Map where Interstate 80 Median Barrier, Paving & Lighting Safety Project will take place from Interstate 80 Albany to Hercules and through the Carquinez Bridge area.

Where: I-80 Albany to Hercules and through the Carquinez Bridge area

When: In Progress, expected to be completed Fall 2025

Why: Caltrans is replacing 10.5 miles of median barrier and adding new lighting to enhance safety and ease of mobility for motorists. Additional upgrades include drainage systems, guardrails, and pavement resurfacing.

Note:

  • Overnight lane and ramp closures Monday – Friday only
  • Temporary traffic shifts in place
  • CHP and signage on-site to guide motorists
  • Noise and lighting concerns addressed proactively

💡 State Route 4 Paving & Lighting Project

State Route 4 highway shield.

Where: SR-4 From Contra Costa County line to east of South Whiskey Slough Rd

When: Ongoing

Why: Have you been wondering what is going on SR-4? Caltrans’ work on SR-4 involves repairing existing asphalt concrete (AC) in the form of dig-out operations.  When the dig-out work is complete, resurfacing of SR 4 is expected to be completed by the end of 2025, weather-permitting.Both westbound and eastbound SR 4 (17 miles total) within the project limits will be resurfaced at the conclusion of the project.Caltrans enhancements are being implemented to improve safety and road quality. This project also includes traffic management and new signage installations.


🔄 I-680/SR-4 Interchange Enhancements

Where: I-680 and State Route 4 Interchange (Martinez area)

When: Under Construction

Why: This project is designed to reduce congestion and improve traffic flow in one of the county’s busiest corridors. Enhancements will streamline merging movements and make commutes safer and more efficient. For more information visit: https://ccta.net/projects/interstate-680-state-route-4-interchange-improvements/


🛣️ I-680 Northbound Express Lane Completion

Where: Between Livorna Road and SR-242

When: Planned through 2027

Why: In partnership with the CCTA, Caltrans is closing the express lane gap to alleviate bottlenecks and improve commute times for northbound I-680 travelers. This will provide a more seamless express lane experience from the San Ramon Valley to Concord. For more information visit: https://ccta.net/projects/innovate-680/express-lane-completion/


🦺 SR-123 San Pablo Avenue Preventive Maintenance

Photo of San Pablo Ave (SR-123) Carlson Blvd to I-80 (El Cerrito & Richmond).

Where: San Pablo Ave (SR-123) Carlson Blvd to I-80 (El Cerrito & Richmond)

When: On going

Why: The purpose of this project is to preserve and extend the life of the existing pavement and improve ride quality. Upon completion, commuters will enjoy a smoother ride along State Route 123. This work includes safety lighting (31 locations), detector loops, sidewalk and curb/gutter enhancements. Supports smoother travel and safer pedestrian experience.


UPCOMING PROJECTS

🦺 Appian Way Overcrossing

Interstate 80 highway shield.

Where: Appian Way in Pinole

When: Tentative scheduled dates for two 55-Hour full closure of Southbound Appian Way the weekends of August 15, 2025 and August 22, 2025.

Why: Caltrans plans two Full Closures of the Appian Way Overcrossing in the Southbound direction paired with nightly lane closures through Spring of 2026. This work will consist of making Improvements on overcrossings to ensure structural integrity and user safety for all.


🦺 I-680 Pavement Preservation

Caltrans workers at worksite for Interstate 680 pavement Preservation project.

Where: I-680, PM R0 to R7.7 (San Ramon & Danville)

When: PS&E by 6/2/25, Construction Winter 2025

Why: Caltrans will grind down old pavement and add a new rubberized layer to help the road last longer and keep the express lanes running smoothly and safely.


🌉 I-580 Richmond–San Rafael Bridge Corridor Enhancements

Map of where Interstate 580 Richmond–San Rafael Bridge Corridor Enhancements project will take place near the city of Richmond, on Interstate 580 between Regatta Boulevard Interchange and the east end of the Richmond-San Rafael Bridge.

Where: Near the city of Richmond, on Interstate 580 between Regatta Boulevard Interchange (PM 0.2) and the east end of the Richmond-San Rafael Bridge (PM 6.3).

When: Upcoming

Why: The Richmond-San Rafael Bridge Open Road Tolling and I-580 Westbound High Occupancy Vehicle (HOV) Lane Extension Project is underway to support a cleaner, safer, and more efficient transportation system.

Project highlights include:

  • Converting a general-purpose lane to an HOV lane.
  • Removing existing toll booths and installing new toll gantries east of the plaza.
  • Realigning the westbound Stenmark Drive on-ramp.
  • Building a dedicated toll gantry for the westbound Stenmark Drive on-ramp.
  • Electrical Substations: Infrastructure upgrades are enhancing reliability.
  • 🚴Bridge Path: The 24/7 bike/ped path remains open while future operating hours are under review.

🛣️SR-24 Caldecott Tunnel Bores 1–3 Rehabilitation and Ventilation Upgrade

Black and white photo of State Route 24 Caldecott Tunnel Bores 1,2, and 3.
Historic photo of the Caldecott Tunnel bores 1,2 and 3

Where: SR-24 Caldecott Tunnel, in Bores One, Two and Three, between Contra Costa and Alameda Counties.

When: Upcoming

Why: A full structural and system upgrade is underway to preserve the structural integrity of the tunnels, improve ventilation performance and firefighting operational response. For more information visit: Caldecott Tunnel Bores 1, 2, and 3 Rehabilitation and Ventilation Upgrade | Caltrans


Current 2025 Contra Costa County Maintenance Highlights Overview. Maintenance data are current estimate at the time of editing, for more information contact the Caltrans Contra Costa County Public Information Officer.

Thank you for staying connected — and as always, please Slow for the Cone Zone!

Setting the PACE: Public Affairs Customer Engagement Site is Now Live!

Banner image for Caltrans District 4 PACE (Public Affairs Customer Engagement). Besides the name, banner includes the Caltrans logo in an orange circle that has a headset around it..

District 4 is proud to announce the launch of our new Customer Service Request (CSR) platform. PACE, the Public Affairs Customer Engagement site, provides a regularly updated breakdown of services requested and rendered across the district.

  • The CSR dashboard aims to provide an overview of the responsiveness to maintenance services requested across the nine Bay Area counties.
  • The data represented as month-to-date falls within a rolling 30-day Service Level Agreement (SLA) and is updated weekly.
  • We strive to close 60% (or more) of all monthly service requests received via the CSR website portal.
  • For more information or to leave comments/suggestions, please contact D4CSLTEAM@dot.ca.gov.
  • To report a highway issue/problem, please submit a CSR ticket through the Customer Service Request Form.

The Contra Costa County newsletter will be distributed on a regular schedule.

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For 24/7 traffic updates, please visit 511.org or https://X.com/511SFBay
For real-time information, please visit Caltrans QuickMap:  https://quickmap.dot.ca.gov

CONTACT:

Contra Costa County Public Information Officers
DeNise Harding

East Bay Branch Chief
Gia Whiteside

General Information
(510) 286-4444