The National Transportation Safety Board is urging the owners of 68 bridges in 19 U.S. states to figure out whether their spans are at risk of collapsing if hit by a ship.
The bridges include both spans of the Chesapeake Bay Bridge, the Golden Gate Bridge, the new Sunshine Skyway Bridge in Florida, the Chicago Skyway Calumet River Bridge and the Verrazzano-Narrows, George Washington and Brooklyn bridges in New York City.
The NTSB recommendation comes nearly a year after Baltimore’s Francis Scott Key Bridge crumpled on March 26, after being struck by the container ship Dali. The bridge was built before risk threshold standards were established by the American Association of State Highway and Transportation Officials.
The Key Bridge’s risk threshold was more than 30 times beyond the acceptable level established by the guidelines.
Like that bridge, the 68 bridges the NTSB wants evaluated also predate the adoption of the 1991 guidelines and the 1994 Federal Highway Administration mandate that new bridges be designed to minimize the possibility of a collapse if hit by a ship, the NTSB said Thursday.
The guidelines were adopted after the 1980 partial collapse of the Sunshine Skyway Bridge in Florida’s Tampa Bay area after a vessel strike.
Half of the bridges are considered critical and essential to the operation of the country’s strategic highway network, while the other half are considered typical bridges, according to the NTSB.
While the federal agency is not suggesting that the bridges are guaranteed to collapse, it wants their owners to evaluate the risks of ship strikes and chances of bridge collapses so that they can take preemptive safety measures.
