bridge was retrofitted with vibration isolators and additional foundation work (widening footings and adding pilings) was performed to upgrade the seismic resistance from 1996–97 prior to the transfer of ownership from the Port of Long Beach to Caltrans. Issues At the time of its completion in 1968, traffic was projected to be modest and mainly limited to workers commuting to jobs at the Long Beach Naval Shipyard. When the Long Beach NSY was closed in 1997, that land was converted and served as home to one of the busiest container terminals in the United States, resulting in greater cargo truck and marine traffic. By some estimates, truck traffic across the bridge tripled in the years following the closure of the Long Beach NSY. By 2010, the vertical clearance of the 1968 bridge was one of the lowest for a commercial seaport, especially at the Port of Long Beach, which remains one of the busiest container ports in the United States. In addition, the bridge was not designed for the traffic it carried (62,000 vehicles daily in 2012), and the added stress was causing pieces of concrete to fall from the bridge's underside, forcing the Port of Long Beach to install nylon mesh "diapers" in 2004 to catch these chunks. Studies to widen the bridge were funded in 1987. Caltrans rated the structural sufficiency of the Desmond Bridge at 43 points out of possible 100 in 2007. Also, since the 1968 bridge roadway lacks emergency/breakdown lanes, multiple lanes would be shut down in the event of an accident, snarling traffic. Other deficiencies cited include the steep approach grades (5.5 percent on the west side and 6 percent on the east side) Competition in the marine shipping industry meant shipping companies were interested in boosting operating efficiency, mainly by building ever-larger container ships. The Gerald Desmond Bridge became a barrier for large ships entering the Inner Harbor at Long Beach, with its restrictive vertical clearance. This restrictive vertical clearance was cited as a factor in an observed drop in the Port of Long Beach's share of United States container imports. According to U.S. census data, the ports of Long Beach and Los Angeles handled 32% of U.S. container imports in 2013, down from 39% in 2002. Port officials estimated that 10% of all waterborne cargo in the United States passed under the Desmond Bridge (either going to or coming from the Ports