Project Details

JV Partner
California Department of Transportation
$240.7 million
April 2000
Start Date
October 2004
Completion Date

Building Carquinez Suspension Bridge

The Carquinez Suspension Bridge carries traffic westbound on I-80 over the Carquinez Strait just north of San Francisco. Flatiron constructed a three-span 3,465-foot-long structure that became North America’s first suspension bridge of its kind to be built in 35 years. At bid time, it was the largest project ever awarded by the California Department of Transportation.

Each 407-foot-tall tower is supported by 12, three-meter-diameter and 90-meter-long rock-socketed drilled shaft piles. Reinforced concrete pile caps transfer vertical and lateral loads between the piles and the towers.

The suspended superstructure utilizes a steel orthotropic deck section 1,056 meters in length. The 24 deck sections were transported on three ocean-going vessels from Japan and jacked into place directly from the ship using the bridge’s main suspension cables. The bridge is designed to withstand both major wind and seismic disturbances.

3,465-foot orthotropic steel box girder bridge suspended by twin 407-foot-tall concrete towers

Two 1.7-foot-diameter cables made up of 13,200 miles of wire

24 steel deck sections, weighing an average of 600 tons each

380 anchorage piles

Site subject to strong currents, winds and fog

Constructed in Carquinez Straits, active shipping lane under U.S. Coast Guard jurisdiction

Associated General Contractors of America
Build America Award 2003
Associated General Contractors of America
Safety Excellence on a High Hazard Job 2000, 2003
Associated General Contractors of America
Meeting the Challenge of the Difficult Job Heavy Engineering 2004
Consulting Engineering & Land Surveyors
Engineering Excellence Award 2004