Martinez, CA — The Contra Costa Transportation Authority (CCTA) and the California Department of Transportation (Caltrans) are constructing the first phase of a multi-phased project to improve safety and help reduce congestion at the Interstate 680/State Route 4 Interchange in central Contra Costa County.
In order to facilitate the setting of overhead girders that will support the replacement of the highway 4 bridge over Grayson creek, and ensure crew and public safety during this operation, temporary nighttime freeway closures in both directions will occur for a total of nine nights.
Freeway traffic will be detoured onto Imhoff Way between Solano Way and Blum Road in Pacheco. This work has been scheduled during nighttime hours to minimize impacts to commute-hour traffic.
Planned Nightly Full Closures of Both Directions of SR-4 at the I-680 Interchange:
Friday, August 23 through Thursday, August 29
Tuesday, September 3 and Wednesday, September 4, 2019
Lane Closures start at 10:00 p.m.
Full Freeway Closures are scheduled between 11:00 p.m. and 5:00 a.m.
Freeway will be opened between 5:00 a.m. and 6:00 a.m.
Motorists are advised to be alert for on-site closure and detour signs, and to Slow for the Cone Zone. Please drive with caution through the detours and leave a safe traveling distance between your vehicle and vehicle ahead of you.
About the Interstate 680/State Route 4 Interchange Improvement Project
The Interstate 680/State Route 4 Interchange Improvement Project will widen approximately four miles of State Route 4 in both directions between Morello Avenue in Martinez and State Route 242 by adding a third lane in the eastbound and westbound directions to improve on-ramp and off-ramp merging. The project also includes widening of five structures, extending eastbound State Route 4’s carpool lane approximately two miles, installation of safety lighting, and replacement of the Grayson Creek Bridge to bring it up to current State bridge safety codes. This segment of work in this multi-phased project will lay the groundwork for future improvements to connector ramps, improve traffic safety and enhance traffic flow.
