Updates to Overnight Full Closures on State Route 4 Now Scheduled Between Balfour Road and Marsh Creek Road in Contra Costa County

Nightly Full closures continue from 7:30 PM to 5:00 AM

Contra Costa County - Caltrans has revised the area affected by the full closure needed for ongoing paving on State Route 4 (SR-4), spanning from Hillcrest Avenue to Byron Highway. The updated closures will occur each night between Balfour Boulevard and Marsh Creek Road along SR-4, beginning May 26, 2026, through May 28, 2026. Additionally, a tentative closure is planned for Sunday, May 31, 2026, nightly from 7:30 PM until 5:00 AM. Full Closure of Marsh Creek Road (Sr-4) is set to return Monday, June 1, 2026. Access during these times will be limited to local residents, business owners, and their employees.

Please note: all scheduled work is weather dependent and may change.

SR-4 Balfour Road to Marsh Creek Detour Information May 26-28 (5/31 tentative):

Westbound SR-4 Travelers:

Traffic from Byron and Discovery Bay to Antioch/Martinez : Turn right on Walnut Blvd , continue Walnut Blvd, turn left on Balfour Rd., continue, Balfour Rd., turn right on Balfour Rd on to WB SR-4 on ramp and merge WB SR-4.

Traffic from Livermore and Byron to Antioch/ Martinez: Turn right on Walnut Blvd, continue Walnut Blvd, turn left on Balfour Rd., continue Balfour Rd., turn right on Balfour Rd. WB SR-4 on ramp and merge WB SR-4.

Eastbound SR-4 Travelers:

Traffic from Antioch/Martinez to Discovery Bay/ Byron: Take EB SR-4 Balfour Rd. Exit, turn left on Balfour Rd., continue Balfour Rd., Turn Right on Walnut Blvd, Turn Left on Marsh Creek( SR-4).

Traffic from Antioch/Martinez to Livermore: Take EB SR-4 Balfour Rd. Exit, turn left on Balfour Rd., continue Balfour Rd., Turn Right on Walnut Blvd, continue Walnut Blvd, turn left on Vasco Road.

WHAT TO EXPECT

Drivers should note that Marsh Creek Road (SR-4) will be fully closed overnight, beginning again on June 1, 2026. The closure will take place every Sunday through Thursday night from 7:30 PM to 5:00 AM. To search for current District 4 lane closure information, please click here. This project is tentatively scheduled to be complete by Summer 2027.

State Route 4 Marsh Creek Road Detour Returns June1, 2026:

• Westbound SR-4 Travelers: Detour begins at Byron Highway left on Brentwood Boulevard, left on Balfour Road, right on to westbound SR-4.

• Eastbound SR-4 Travelers: Detour begins at Vasco Road; left on Walnut Boulevard, right on Payne Ave, left on Sellers Ave, right on Brentwood Boulevard, continue on Byron Hwy to eastbound SR-4.

Changeable message signs (CMS) will be posted throughout the corridor to assist drivers. Please follow posted signs and detour routes during these closure periods.

Motorists are advised to expect delays and allow extra travel time. For 24/7 traffic updates, follow 511.org on X. For real-time traffic, visit Caltrans QuickMap.

^{Crews conducting paving work on SR-4 Marsh Creek Road in Contra Costa County}

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.