Interstate 680 / State Route 4 Interchange Improvements

Central County
PROJECT BUDGET $443.6 Million
Martinez, Pacheco, and Concord.

The I-680/State Route 4 interchange reconstruction will be the largest transportation highway project in Contra Costa County following the completion of the Caldecott Tunnel Fourth Bore and State Route 4 Widening projects.

The purpose of this project is to increase the capacity and safety of the Interstate 680/State Route 4 Interchange. The proposed project will provide congestion relief and improve traffic operations within the interchange area.

The State Route 4 East corridor serves as the only major east-west transportation link joining the communities of Antioch, Bay Point, Pittsburg and Brentwood with central Contra Costa County and the Bay Area.

The Interstate 680 corridor serves as the main artery through central Contra Costa County, connecting it with Solano County to the north and Alame ...more