OAKLAND, CALIF. —Caltrans reached a milestone with the breakthrough of the top portion of the Caldecott Tunnel's fourth bore — joining the tunnel's eastern and western sides and bringing the region one step closer to traffic congestion relief. When the fourth bore opens to traffic in late 2013, it will eliminate the need to reverse the traffic direction in the existing center bore twice a day to accommodate peak traffic flows, with dedicated westbound and eastbound traffic lanes.

The Caldecott Fourth Bore Project is a partnership between the Federal Highway Administration, Caltrans, the Metropolitan Transportation Commission (MTC), the Contra Costa Transportation Authority (CCTA), and the Alameda County Transportation Commission (ACTC). The $391 million project is primarily funded ($180 million) through the American Recovery and Reinvestment Act of 2009 (Recovery Act); through a local transportation sales tax (Measure J) passed by Contra Costa voters in 2004; and by Regional Measure 2 (Bay Area bridge tolls).

"With significant federal, state, regional and local support, this project serves as a prime example of how all levels of government have come together to improve California's infrastructure," said Acting Caltrans Director Malcolm Dougherty.

"The fact that the Caldecott Fourth Bore Project is one of the largest recipients of Recovery Act funding in the nation is a true testament to the regional importance of this project," said Steve Heminger, Executive Director of the MTC.

"It is quite an achievement that it has taken us just slightly more than a year to reach this important milestone," said Randy Iwasaki, Executive Director of the CCTA. "The infusion of federal funds, in addition to local Measure J regional funds, has enabled us to move forward with this essential mobility project, which will improve the quality of life in Contra Costa and Alameda Counties, and in the region overall."

Work to build a fourth bore north of the existing tunnels began in January 2010. Excavation began on the eastern side (Orinda) in August 2010 and on the western side (Oakland) in March 2011. Today's breakthrough marks the completion of the top portion excavation and demonstrates the rapid progress the project has made since tunneling began.

"We are pleased to be a part of this project to improve connectivity between our two counties," said Art Dao, the Executive Director of the ACTC.