CHAPTER 3: CONTRA LOMA

Creativity in Construction

http://Nighttime%20bridge%20demolition%20work

Nighttime bridge demolition work

http://Crews%20getting%20ready%20for%20bridge%20demolition

Crews getting ready for bridge demolition

http://Dust%20control%20for%20bridge%20demolition

Dust control for bridge demolition

http://Dust%20control%20for%20bridge%20demolition

Dust control for bridge demolition

http://Pouring%20concrete%20for%20new%20Highway%204%20lanes

Pouring concrete for new Highway 4 lanes

http://Laying%20the%20base%20for%20the%20new%20Highway%204%20lanes

Laying the base for the new Highway 4 lanes

http://Retaining%20wall%20detail

Retaining wall detail

http://Guiding%20steel%20beams%20for%20bridge%20construction

Guiding steel beams for bridge construction

http://Guiding%20steel%20beams%20for%20bridge%20construction

Guiding steel beams for bridge construction

http://Securing%20steel%20beams%20for%20new%20bridge

Securing steel beams for new bridge

http://Retaining%20Wall%20Construction

Retaining Wall Construction

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, the Contra Costa Transportation Authority (CCTA) ensured that project work included a full diamond interchange at Contra Loma Boulevard / L Street and elimination of the G Street on- and off-ramps. As many schools are positioned off of G Street, the removal of the G Street ramps was especially helpful to the circulation of local school traffic.

Given this segment’s proximity to Antioch Creek, construction work for Contra Loma Boulevard encountered a unique challenge: preservation of endangered species. The U.S. Army Corps of Engineers’ Regulatory Program governs the protected waters of Antioch Creek and, for this particular permit, stipulated that no construction work could be completed between the months of October and April in order to minimize disruption to local wildlife. At times, this “prohibited work window” required creative management of construction activities and resources so that these critical endangered species, the California red-legged frog (Rana draytonii), could remain undisturbed. Despite this challenge, and thanks to CCTA’s creative approach to construction management, work on this segment was completed on schedule.

“The Metropolitan Transportation Commission is glad to work with our partners to help meet growing traffic demand while protecting our natural environment. We recognize that this benefits not only the cities along this corridor but also the entire Bay Area region.”
– Federal Glover, Metropolitan Transportation Commission

Highlights

timeline iconTimeline: March 2012 to January 2016
segment iconSegment: Contra Loma Boulevard / L Street & G Street Overcrossing to Lone Tree Way / A Street
mileage iconNew lane miles added: 3.95
investment iconCapital investment: $48.7 million
contractor iconContractor: C.C. Myers, Inc., Rancho Cordova, CA

Key Enhancements

  • Widened Highway 4 from four to eight lanes, including a High-Occupancy Vehicle lane in the eastbound and westbound directions
  • Reconstructed the Contra Loma Boulevard / L Street partial interchange to a full interchange to provide additional local street capacity, upgraded signalized intersections, and ramp metering capabilities
  • Removed partial ramp access and reconstructed the G Street Bridge to accommodate the Highway 4 Widening and BART median improvements, resulting in additional local street capacity and an upgraded signalized intersection at G Street and E. Tregallas Road
  • Constructed the BART median, including a BART bridge over L Street / Contra Loma Boulevard
  • Constructed auxiliary lanes in the eastbound and westbound directions of Highway 4