Here is a look at upcoming road construction impacts in Contra Costa County via CALTRANS and Contra Costa County Public Works.
February 5
- Clayton – Contra Costa County Public Works issued a permit to PG&E for a closure of Morgan Territory Road between Finley Road and 7007 Morgan Territory Road to through traffic on Thursday, February 5, 2026, barring unforeseen circumstances. The closure will occur from 8:00 a.m. to 5:00 p.m., weather permitting. Traffic control will be used. Flaggers will be on site to assist with intermittent passage for local traffic and emergency vehicles to ensure public safety during their operation. The closure to through traffic is necessary for PG&E to replace an existing utility pole in preparation for the Marsh Creek Road Bridge Replacement Project at Morgan Territory Road, Post Mile 5.0. Signs will be posted at the intersection of Marsh Creek Road and Morgan Territory Road and near the “Morgan Territory Staging Area” to alert through traffic of the closure. Upon completion of the work, the roadway will reopen to normal traffic. To learn more about this project, visit www.contracosta.ca.gov/Marsh-Creek-Road-Bridge-Replacement-at-Morgan-Territory-Road
- Danville: Caltrans will conduct a full closure of the El Cerro Boulevard on-ramp to southbound I-680 in the Town of Danville, Thursday, February 5, 2026 from 7AM-3PM. For the safety of our crews and the motoring public. — more info
February 9
- Brentwood – The Contra Costa County Public Works Department will repair delineators to enhance safety on Vasco Road between Camino Diablo and the Alameda County Line on Monday, February 9, 2026, barring unforeseen circumstances. The work will occur from 9:00 a.m. through 4:00 p.m., weather permitting. The work will be scheduled to minimize impacts to commute traffic. Message boards will be posted to advise drivers of the scheduled work. A pilot car will be used to direct traffic through the work area. Drivers can expect delays of 20-30 minutes and are encouraged to use alternative routes.
February 9-12
- Alameda and Contra Costa Counties – Caltrans has scheduled overnight closures of Bores 1, 2 and 3 of the Caldecott Tunnel on State Route 24 (SR-24) for tunnel washing, routine maintenance, and drainage cleaning. All work is weather dependent. Closure Schedule of SR-24:
- Bore #1 Closure EB SR-24: Monday February 9, 2026, and Tuesday, February 10, 2026 – closed from 10:00 PM to 4:30 AM
- Bore #3 Closure WB SR-24: Wednesday, February 11, 2026 – closed from 10:00 PM to 12:00 AM
- Bore #2 Closure EB SR-24: Thursday, February 12, 2026 – closed early morning 12:00 AM to 4:30 AM and overnight 10:00 PM to 4:30 AM the following day,(Feb.13th)
- More info: Click Here
Ongoing
Caltrans to Begin SR-4 Old River Bridge Maintenance Project
SAN JOAQUIN COUNTY – Caltrans will soon begin a bridge maintenance and preservation project that will make necessary upgrades and repairs of the Old River Bridge on State Route 4 (SR-4), located at the San Joaquin/Contra Costa County line, east of Discovery Bay.
This project is required to install a new polyester concrete overlay to the bridge deck (roadway) surface, install new guardrail systems located at the approaches of each end of the bridge, and painting of the bridge steel structure with weather-resistant paint and materials to increase the reliability and serviceability of this 100-year-old swing span bridge.
Additional in-water work will see the existing timber waling and the fenders on the north side of Pier 3 replaced, while the south side of Pier 2 would be supported with new high-density polyethylene walers mounted to the existing timber piles.
This $9.8 million project will be performed by Disney Construction, Inc. (Burlingame, CA) and is scheduled for 220 working days beginning the week of January 25-31, with completion expected on November 10, 2026 (weather permitting).
REQUIRED HIGHWAY AND BRIDGE CLOSURES:
- Full highway closure of SR-4 at Old River Bridge for construction activities on Sunday, February 1, from 7:00 a.m. until 7:00 p.m.
State Route 4 Detour Information:
- Westbound SR-4 travelers: The detour begins at the Tracy Boulevard intersection; south on Tracy Blvd; west on I-205; north on Mountain House Parkway; northwest on Byron Road to SR-4.
- Eastbound SR-4 travelers: The detour begins at the Byron Road intersection; southeast on Byron Road; south on Mountain House Parkway; east on I-205; north on Tracy Blvd to SR-4.
Long-term, 24-hour, one-way traffic control will be implemented on SR-4 at the Old River Bridge beginning at 7:00 a.m. on Monday, February 2, through November 2026.
- Alternating traffic signals (automated flaggers) will be installed at the east and west ends of the Old River Bridge to control traffic and to allow safe passage for motorists.
- This extended one-way traffic control is required due to various factors including limited availability of safe workspace (no median or shoulders to perform work or stage equipment), environmental and in-water work date restrictions.
- Long-term closure of the Old River Bridge swing-span to marine traffic beginning
Caltrans will utilize roadside and portable changeable message signs alerting motorists of the lane closure and potential delays, which are expected to be approximately 15 minutes. For more information on this project, please visit: https://dot.ca.gov/caltrans-near-me/district-10/district-10-current-projects/10-1h360
All work is scheduled to begin as listed, but is subject to change due to traffic incidents, weather, availability of equipment, and/or materials and construction related issues. For the safety of workers and other motorists, please Be Work Zone Alert. For information on Caltrans’ projects statewide, please visit build.ca.gov