The Contra Costa County Transportation Authority (CCTA) delivers on its promises. For more than 25 years, CCTA has planned, funded, and implemented an abundance of programs and projects that have improved transit accessibility, reduced traffic congestion, supported economic revitalization and enhanced the quality of life in East County.

“CCTA believes that the success of Contra Costa lies in the ability to help ensure safe, reliable mobility for all.”
– Randy Iwasaki, Executive Director, Contra Costa Transportation Authority

Since its inception, CCTA has championed the mobility needs of the more than 250,000 residents of East County. In 1988, Contra Costa voters passed Measure C, generating more than $1 billion over a 20-year period to fund extensive transportation improvements throughout the county. This funding gave rise to CCTA’s Highway 4 Corridor Projects that would reconfigure portions of western Highway 4 to address critical safety and traffic capacity demands. Measure C also enabled the widening of the Willow Pass Grade: the gateway into eastern Contra Costa County.

Highway 4 improvements gained additional momentum in 2004 when voters approved Measure J, extending the benefits of Measure C’s economic investment through 2034. Thanks to Measure J’s 25-year, estimated $2.5-billion overall investment in the county, Contra Costa moved forward with plans to implement numerous transportation improvements. Chief among these crucial enhancements were the widening of five segments of Highway 4 from Pittsburg through Antioch and the preparation for a BART extension to Hillcrest Avenue in Antioch down the highway median.

The widening projects were carefully staged to keep 130,000 vehicles per day moving as major construction and demolition work began. The widening projects, the BART extension, and other interchange improvement projects in the area brought the total investment in East County to $1.3 billion, including State, Federal, Contra Costa Transportation Authority Measures C and J, regional bridge tolls, and other funds.

All told, the projects expanded Highway 4 from four to eight lanes between Loveridge Road in Pittsburg to just west of State Route 160 in Antioch and from two to four lanes from Lone Tree Way to Sand Creek Road in Brentwood; added missing connector ramps at the State Route 160/Highway 4 interchange; and extended BART from Pittsburg to Antioch. On July 20, 2016, a ribbon cutting ceremony celebrated the successful completion of these improvements to modernize eastern Contra Costa County. With the completion of the Highway 4 Corridor Projects, East County residents can now enjoy greatly improved transit accessibility and safety, reduced traffic congestion, and enhanced quality of life.

This “Story through Images” is a tribute to the many entities and individuals involved in ensuring the success of these vital projects.

Thank you!





The Loveridge Road segment was the first phase of the Highway 4 Corridor Projects to enter into construction and the closest to the existing Pittsburg/Bay Point BART terminus. Breaking ground on this segment signified the official start of the corridor improvements — and marked the beginning of six years of meticulously planned construction.



The second phase of the Highway 4 Corridor Projects, the Somersville Road / Auto Center Drive segment was completed in conjunction with the Loveridge Road segment to the west. To minimize disruption to traffic, CCTA scheduled work in highly orchestrated phases, and much of the demolition and reconstruction work for the bridges took place at nighttime during periods of lighter traffic.



The Contra Loma Boulevard / L Street segment was the third phase in the series of the Highway 4 Corridor Projects. Prioritizing roadway optimization for all motorists, CCTA ensured that project work included a full diamond interchange at Contra Loma Boulevard / L Street and elimination of the nonessential G Street on- and off-ramps.



The Lone Tree Way / A Street segment represented the fourth phase in the sequence of the Highway 4 Corridor Projects and, incidentally, was the last segment to be completed. Widening this segment was not just a matter of laying new pavement: three new bridges – an Eastbound Bridge, a Westbound Bridge, and a BART Bridge – all required their own separate stages of construction.



The fifth phase of the Highway 4 Corridor Projects, the Hillcrest Avenue segment signified the highly-anticipated conclusion of construction on the main project corridor, ending in the city of Antioch. Additionally, the lane openings at Hillcrest Avenue marked a significant milestone: the official opening of all westbound highway lanes for the entire corridor.



On July 20, 2016, a community celebration and ribbon cutting ceremony celebrated the completion of the Highway 4 Corridor Projects, a monumental collaboration among the Contra Costa Transportation Authority, the California Department of Transportation, BART, the Metropolitan Transportation Commission, the California Transportation Commission, and the Federal Highway Administration. The midsummer gathering convened public officials and community members to celebrate the culmination of six years of painstaking construction, which involved 40 local vendors representing eight distinct trade professions, including electricians, masons, and teamsters.