Welcome to Caltrans District 4

Caltrans District 4

This project was completed in November 2003. The 1927 span is being dismantled. The following information is about the deconstruction of the 1927 span and construction of the Alfred Zampa Memorial span.

"Traffic Switch" Scheduled for Carquinez Bridge Eastbound Traffic to be Diverted to 1927 Bridge for Two Months. Download:

Press Release

Traffic Map

KRON 4 TV News Story "When the Carquinez Bridge Backup Will End"
by KRON 4 reporter Mark Jones on Oct. 5 >> KRON Page Link | Watch Video

Spanning The Carquinez Strait
Order this limited edition book of historic photographs. Click to download the State Publications Mail Order Form or go to the Publications web page and select to order by Credit Card. You may also call: (916) 323-5606.

A new way to cross the Carquinez Strait

Project Purpose: The bicycle and pedestrian lane on the new Carquinez (Alfred Zampa Memorial) Bridge provides a safe, new transportation connection for non-motorized travel over the Carquinez Strait along westbound Interstate 80. The new bike/ped path links Solano and Contra Costa counties, and closes a gap in the San Francisco Bay Trail and Bay Area Ridge Trail path systems -->> PDF | Word

An Introduction to The Carquinez Bridge

The two structures that bridged the Carquinez Straits until the completion of the Alfred Zampa Bridge played an important role in the Bay Area’s transportation network and were used by more than 109,000 drivers each day. The Carquinez Bridges did not meet seismic design or traffic safety standards and they became the subjects of two major projects to improve the following six transportation needs:

  • satisfy current seismic and safety standards;
  • correct existing roadway deficiencies;
  • improve traffic safety;
  • maintain routes for local, regional, and interstate truck freight movement;
  • encourage use of alternate modes; and
  • support HOV use.

Photo: Bill Hall, Caltrans Distric 4 Photography

The first project involved retrofitting the existing eastbound bridge built in 1958 for safety and seismic stability. The second project replaced the existing westbound 1927 bridge with a suspension style bridge that incorporated the latest construction technology with public amenities such as a pedestrian bike lane and two new vista points. The project is financed by Regional Measure One funds. Regional Measure One is a mandate passed by voters in 1988 to increase tolls on Bay Area bridges to fund improvements to bridge structures and their approaches. The replacement of the Carquinez Bridge Western Span was specifically identified as one of the projects to be funded by this measure.

The eastbound Carquinez Bridge was built in 1958 as part of the route’s upgrade to interstate status. The 1958 bridge carries 53,000 vehicles per day in four eastbound lanes. The total bridge width is 52 feet, including 12-foot lanes and two 2-foot shoulders. The cantilever steel truss spans a total of 3,300 feet in length at 140 feet above the channel.

Photo: Bill Hall, Caltrans Distric 4 Photography

The cost of retrofitting the 1958 structure was $70 million. The contract for this project was awarded on Friday, June 19, 1998 to Balfour Beatty Construction, Inc. Balfour Beatty began preliminary work on Monday, June 22, 1998. Retrofit construction on the 1958 bridge was finished in August 2001.

This project facilitated the following upgrades:

  • replaced or strengthened the steel truss members in the bridge towers;
  • reinforced pile foundations of Pier 5 at the south end of the bridge;
  • retrofitted the abutment where the bridge touches down on the northern end;
  • strengthened the eastbound on/off ramps and approach structure.

The western bridge constructed in 1927 as a private toll bridge provided three lanes of westbound (to San Francisco) traffic. This structure exhibited deterioration of its metal components. Accessibility to and maintenance of the bridge’s structural members was difficult, and major rehabilitation was virtually impossible while the bridge is being used for traffic. A rehabilitation was done so that it can be used during the redecking of the 1958 bridge.

Replacement required State Historic Preservation Officer and Advisory Council on Historic Preservation approval because the existing 1927 westbound main span and westbound Crockett off-ramp are listed in the National Register of Historic Places. The Carquinez Bridge Project expedited replacement of the westbound bridge, reduced traffic disruptions and costs associated with retrofit, and increased the life span of the I-80 crossing. This project also incorporated the following changes and upgrades:
  • alignment of replacement bridge will be west of existing bridges;
  • suspension bridge type requiring only two main piers;
  • pedestrian/bicycle lane on replacement bridge;
  • visual access on both northern and southern shoreline;
  • 1927 bridge superstructure and towers will be demolished and removed;
  • old pier foundations will remain at height of existing fender system to provide protection for the bridges;
  • Contra Costa County extended Cummings Skyway with Caltrans’ participation in funding (completed December 1998);
  • Existing Caltrans maintenance facility in Vallejo was relocated to Benicia.

  • The replacement project cost was approximately $200 million and was completed in late 2003.