Construction on the San Diego–Coronado Bay Bridge started in February 1967. The bridge required 20,000 tons of steel (13,000 tons in structural steel and 7,000 in reinforcing steel) and 94,000 cubic yards of concrete. To add the concrete girders, 900,000 cubic yards of fill were dredged, and the caissons for the towers were drilled and blasted 100 feet into the bed of the bay.
The bridge opened to traffic on August 3, 1969, during the celebration of the 200th anniversary of the founding of San Diego. The 11,179-foot-long (3,407 m or 2.1 mi) bridge ascends from Coronado at a 4.67 percent grade before curving 80 degrees toward San Diego. It is supported by 27 concrete girders, the longest ever made at construction time.
The principal architect was Robert Mosher. Mosher's job was to build a bridge that would provide transportation, allow ships access to the bay, and serve as an iconic landmark for San Diego. Mosher proposed a basic box and girder-style bridge for the framework, with a prestressed concrete and steel deck sitting atop steel girders and supported by towers.
Originally, the toll was $0.60 in each direction. Several years later, this was changed to a $1.00 toll collected for westbound traffic to Coronado only. Although the bridge was supposed to become "toll-free" once the original bridge bond was paid (which occurred in 1986), the tolls continued for sixteen additional years. On June 27, 2002, it became the last toll bridge in Southern California to discontinue tolls, despite objections from some residents that traffic to the island would increase.
The islands upon which the toll booths sat, as well as the canopy over the toll plaza area, are still intact, located at the western end of the bridge in the westbound lanes. Though tolls are no longer collected, beginning February 19, 2009, there was talk of resuming westbound toll collection to fund major traffic solutions and a tunnel. However, nothing came of the discussions, and more recently there have been discussions of removing the unused toll plaza completely.
The bridge contains five lanes; two eastbound, two westbound and a reversible middle lane with a barrier transfer machine installed in 1993, which can be used to create a reversible lane in either direction in response to traffic volume.
Under construction (below) in 1968.
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