With the advent of automobiles, the need for transportation between Oakland and San Francisco increased. Therefore, the California Legislature developed a California Toll Bridge Authority in 1929 which was responsible for the construction of the bridge, joining San Francisco and Oakland. The route that was chosen for the construction of the bridge passes through Yerba Buena Island which was, at that time, being used as a US naval base. This route was chosen as it significantly reduced bridge length, construction cost, and labor. But before starting the construction of the bridge, permission from the US congress was required for the construction over Yerba Buena Island, which was finally obtained in1931.

The realization of Bay Bridge Construction started with the establishment of the California Toll Bridge Authority in 1929 and a number of unemployed people got employment. Initially, fourteen designs were submitted for the Bay Bridge. The final design consisted of a cantilever bridge from Oakland to Yerba Buena and a suspension bridge from Yerba Buena to San Francisco. Both the bridges were joined by boring a tunnel on Yerba Buena Island.

The Bay Bridge was first designed by Charles H. Purcell who was a civil engineer by profession. This was the longest bridge designed at that time and designing and analysis of such a mega project was a big deal at that time. The bay bridge was designed in two sections which were then connected by making use of a tunnel. Both the sections were designed differently according to the climatic conditions and land of both the regions. Also, water depth was not the same in the two areas which were joined by the bridge. The San Francisco region was covered in the western span of the bridge and that portion of the bridge was designed on the principle of the suspension bridge. This suspension bridge was having heightened towers with long spans to provide flexibility and strength to the&nbsp.design. whereas, the eastern section is having a blend of truss and cantilever design.