Carquinez Bridge Replacement, United States of America
The 1927 Carquinez Bridge across the Carquinez Straits, San Francisco Bay area, was replaced with a new twin-tower suspension bridge that opened on 11 November 2003. Construction on the project started early in 2000 and the project cost an estimated $240m.
The original bridge (designed by Robinson & Steinman) was dismantled in 2006 but the other Carquinez Bridge crossing that was first opened in 1958 (a cantilever bridge) received a $70m renovation as part of an upgrade to interstate status. This project was completed by Balfour Beatty in August 2001.
The 1958 bridge carries around 53,000 vehicles per day in the eastbound direction across the strait; the $4 toll is charged on the eastbound direction.
The dimensions of the refurbished bridge are as follows: width is 52ft, including two 2ft shoulders either side, and four 12ft lanes.
The steel cantilever truss structure of the bridge has a total span of 3,300ft and is 140ft above the water of the channel.
The new suspension bridge (Alfred Zampa Memorial Bridge) and the refurbishment were required as the original Carquinez Bridges did not meet seismic design or traffic safety standards required in California.
The bridges carry the eight lanes of Interstate Highway 80 (I-80) over the Carquinez Straits linking Vallejo, in the north, to Crockett in the south.
SUSPENSION BRIDGE REPLACEMENT
The limits of the bridge replacement project were from Cummings Skyway in Contra Costa County to SR 29 in Solano County. The project consisted of the following elements:
- Suspension bridge with two main piers
- Three mixed-flow lanes plus one high occupancy vehicle (HOV) lane and a separate bicycle / pedestrian lane
- New visual access on both northern and southern shoreline
- Demolition and removal of 1927 bridge superstructure and towers (old pier foundations will remain at height of existing fender system to provide protection for the 1958 bridge)
REGIONAL MEASURE ONE
The replacement and refurbishment of the Carquinez Bridges was financed through Regional Measure One, a mandate passed in 1988 to increase tolls on Bay Area bridges to fund future improvements to the bridges and their approaches.
NEW CARQUINEZ BRIDGE FEATURES
- Total length (entire span): 3,465ft
- Middle span length: 2,390ft
- Crocket span: 482ft
- Vallejo span: 593ft
- Bridge width: 84ft
- Tower height: 410ft
- Wind speeds through strait: 15mph to 20mph (24km/h to 32km/h
- Pile diameter: 10ft
- No. of piles (both towers): 24
The contract was awarded to a joint venture of FCI Contractors Inc. and Cleveland Bridge California Inc. with a bid of $188m and 1,000 days. Lim & Nascimento were responsible for deck segment fabrication and Buckland & Taylor Ltd supplied construction engineering services on Pier P1.
The next bid was $209m and 920 days by a joint venture of American Bridge Co. and Kiewit Pacific Co.
CARQUINEZ BRIDGE TRAFFIC SWITCH PROJECT
As part of an ongoing upgrade to the 1958 bridge which is constantly in use, a project was instigated in September 2005 to upgrade and repair the deck of the 1958 bridge.
During the period from 25 September to 11 November 2005 eastbound traffic was temporarily switched over to the original 1927 bridge, which had not been used since the opening of the new crossing in 2003.
The Traffic Switch project allowed the worn deck on the approach road to the bridge to be repaired by Caltrans using new construction methods and materials. The 1958 bridge also underwent a strict seismic survey and received further structural rehabilitation. On switching the traffic back the road layout retained a new Fastrak lane and toll booth for use by commuters.
The 1927 span was completely dismantled by September 2007. The process started in March 2006 and cost $49.7m after a review by Bechtel Corp increased the cost of demolition from the previous unrealistic $18m.