The new Interstate 680 auxiliary lanes between Danville and San Ramon are set to open beginning this week, officials said Monday.
The northbound auxiliary lane, between Sycamore Valley and Crow Canyon roads, is scheduled to open Friday (June 27) while the southbound lane through the same area is set to to open July 1.
The lanes connect the on-ramp at one exit with the off-ramp at the next exit. The Contra Costa Transportation Authority (CCTA) and Caltrans hope the additional lanes will limit congestion and make it easier for drivers to merge on and off the freeway.
"The completion of the Auxiliary Lanes represents another project delivered through an investment by Contra Costa voters in their transportation infrastructure," according to CCTA executive director Randell Iwasaki.
Construction, which began in March 2013, involved widening the roadway to add the auxiliary lanes and provide a 12-foot-wide shoulders.
Opening these two new lanes is the final stage of a three-phase project that first started eight years ago. The $54.5 million project included other auxiliary lanes placed between Diablo and Sycamore Valley roads, which has been in use since 2006, and lanes between Crow Canyon and Bollinger Canyon roads, which opened in 2007.
New sound and retaining walls were also constructed as a part of the project.
Once the new lanes are open, other roadwork is scheduled to continue taking place in the freeway median but should be completed by July 25, according to CCTA.
Landscaping work, including adding approximately 4,000 trees and shrubs to each side of the freeway between Sycamore Valley and Crow Canyon roads, is set to begin later this year, with completion expected sometime during 2015, CCTA officials said.