San Francisco-Oakland Bay Bridge Construction | California, US

WSP was retained to repair a section of the San Francisco-Oakland Bay Bridge after the Loma Prieta earthquake.


  • San Francisco, California, USA


  • American Bridge-Fluor JV

Repairing the world’s largest self-anchored suspension bridge

The concept of constructing a bridge linking San Francisco with Oakland has existed since the early 1870s. In 1936, the longtime dream of linking the two locations was finally realized, and the nearly 5-mile-long San Francisco–Oakland Bay Bridge was officially opened to traffic.

On October 17, 1989, a section of the eastern span of the San Francisco–Oakland Bay Bridge between Yerba Buena Island and Oakland collapsed during the Loma Prieta earthquake. American Bridge-Fluor, a joint venture between American Bridge Company and Fluor Corporation, was selected to construct the replacement of the eastern span of the bridge.

WSP was retained by American Bridge-Fluor to provide lead construction engineering services for the project. In that role, the company:

  • Designed 14 falsework piers in San Francisco Bay in anticipation of the suspension cable installation.
  • Designed the lifting frame and gantry used to erect the 540-foot-high permanent main tower.

WSP provided engineering services for the girder fabrication, main cable and suspension installation, and load-transfer procedure for the structure. The firm’s work included:

  • Developing the cambered shape of deck girders for fabrication.
  • Computing the geometry of the main cables and the lengths of the suspenders during erection.
  • Preparing detailed procedures for the load-transfer of the bridge superstructure from the falsework to the suspension system.

The restored structure — designed to withstand extreme seismic and other adverse weather conditions — is the world's largest self-anchored suspension bridge.