Traffic Advisory: Thirteen Nights of Full Freeway Nighttime Closures Planned for the Interstate 680/State Route 4 Interchange

For Immediate Release

Thursday, August 29, 2019

Contact Information

Linsey Willis

Contra Costa Transportation Authority


Alejandro Lopez

California Department of Transportation


Issued By


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 widening of the highway 4  bridge over I-680, and ensure crew and public safety during this operation, temporary nighttime freeway closures in both directions of the Interstate 680 and State Route 4 Interchange will occur for a total of thirteen nights. This work has been scheduled during nighttime hours to minimize impacts to commute-hour traffic. We do not anticipate any weekend work.

  • Here are some facts and figures about the materials and equipment required to complete this work:
  • There are 12 girders per bridge span (a “span” is the distance between two intermediate supports for a structure) and 36 girders total for the entire bridge.
  • The construction team will erect 6 girders each night that are each 4-feet tall, between 72 and 100 feet long, and weighing between 74,000 and 103,000 pounds.
  • 2 Crawler Cranes will be used to erect the girders (a “Crawler Crane” is a type of mobile crane that moves on crawler tracks that provide extra stability).
  • Each Crawler Crane has a 350-ton capacity, a working radius of 150-feet and a boom height of 250-feet.

Planned Nightly Freeway Full Closures of I-680 at the I-680/SR4 Interchange:

Wednesday, September 4 through Friday, September 6, 2019
Monday, September 9 through Friday, September 13, 2019
Monday, September 16 through Friday, September 20, 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 on 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. We appreciate everyone’s patience and cooperation as we work to complete these important improvements.

Please see closure and detour maps below.

I680 closure map CC v5 NB Circlepoint 082619 Final
I680 closure map CC v5 SB Circlepoint 082619 Final
About the Interstate 680/State Route 4 Interchange Improvement ProjectThe 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.