Agencies break ground on major California interchange improvement project


The Contra Costa Transportation Authority (CCTA) and the California Department of Transportation (Caltrans) have broken ground on one of the largest capital projects to be funded under the state’s Senate Bill 1 (SB 1) infrastructure improvement program.

The two agencies have announced the start of construction on the first phase of a multiphased project to improve safety and help reduce congestion at the Interstate-680/State Route 4 Interchange in central Contra Costa County. The initial phase of construction involves widening a 4 mile long (6.4km) segment of State Route 4 in both directions between Morello Avenue in Martinez and State Route 242. This phase of work also involves the replacement of the Grayson Creek Bridge to bring it up to current State bridge safety codes. Breaking ground for this segment of work in this multiphased project will lay the groundwork for future improvements to connector ramps, improve traffic safety and enhance traffic flow. The total cost for improving this segment is approximately US$136m.

Interstate 680 serves as the main artery for motorists traveling through central Contra Costa County, connecting it with Solano County to the north and Alameda and Santa Clara counties to the south. State Route 4 serves as the only major east-west transportation link joining the communities of Antioch, Bay Point, Pittsburg and Brentwood with central and western Contra Costa County and the Bay Area. The I-680/SR 4 Interchange Improvement project will widen the designated section of State Route 4 by adding a third lane in the eastbound and westbound directions, and improve on-ramp and off-ramp merging actions. The project also includes the widening of five structures, extending eastbound SR 4’s carpool lane by approximately 2 miles (3.2km), installation of safety lighting, and replacement of the Grayson Creek Bridge, which is over 50 years old and has exceeded its serviceable life.

“Improving the I-680/SR4 Interchange has been a priority for the Contra Costa Transportation Authority for many years,” said CCTA board chair, Federal Glover. “Thanks to an infusion of Senate Bill 1 funds from the State, we are able to take this first, important step in improving safety at this critical interchange.”

California State Assembly member, Tim Grayson, commented, “For too many years we have neglected our infrastructure, and as a result Californians spend too much time in traffic, too much money on car repairs, and far too little time with their friends and families. I have been working for over two years with the California Transportation Commission and Contra Costa Transportation Authority to fund and break ground on this long-awaited project so that our community can spend less time sitting in traffic and more time doing what they enjoy.”

Caltrans District 4 director, Tony Tavares, noted, “This project will reduce the travel time for the more than 100,000 people who drive this corridor each day, and is a key piece of an ambitious regional improvement plan. The funding from Senate Bill 1 is enabling Caltrans and the Contra Costa Transportation Authority to rebuild California’s highways.”

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Rachelle joined Traffic Technology International in early 2016 after having worked for an HR magazine and prior to that, as a freelance sub editor for various lifestyle consumer magazines. As deputy editor, she supports the editor in making each issue and updating the website. Outside of work, she enjoys tap dancing, playing the piano and video games, and eating spicy food.