Bridges on the Mississippi River that were built around the time of or before the recently collapsed Francis Scott Key Bridge in Baltimore should be evaluated for their vulnerability to a boat collision, the mayors of the cities and towns along the river.
Norma Jean Mattei, past president of the American Society of Civil Engineers, made the assessment after the Key Bridge, built in 1977, was struck by a container ship and fell into the Patapsco River on March 26.
Participating in a March 28 press conference hosted by The Mississippi River and Towns Initiative (MRCTI), a coalition of more than 100 mayors along the Mississippi River from Minnesota to Louisiana, Mattei cited several bridges that may need evaluation: the Vicksburg Mississippi Bridge, which was built in 1930, the Crescent City Bridge in New Orleans, which opened in 1938, the Hughey Bridge. P. Long Bridge in Jefferson Parish La., which dates from 1935, and the Hale Boggs Memorial Bridge in St. Charles Parish, Louisiana, which opened in 1983.
He said that until 1991, bridges were not required to be assessed for potential ship collision risk.
“Many of our crossings [on the Mississippi] they’re older and maybe they’ve never had a full-fledged ship collision assessment, so that’s a lesson learned,” he said.
While not all bridges will need to be evaluated, Mattei said the intervals at which some bridges must be evaluated and triggers, such as a change in the frequency or type of river traffic, should be established.
“A trigger can be an increase in vessel traffic or the size or type of vessels,” he said. “We should look at those bridges where larger ships can pass compared to what we’re used to seeing.”
He noted that the Mississippi River generally does not see traffic of the type of massive container ship that hit the Key Bridge. However, as ENR reported in 2022, a $238 million effort is underway to deepen the lower Mississippi River and will allow larger “Post Panamax” shipping vessels to use the waterway and ports of access to the lower river.
The term “Post Panamax” refers to the 2016 expansion of the Panama Canal that created new locks to accommodate large ships.
Mattei noted that other factors, such as the speed of river waters, could also play a role in an assessment and boats coming into contact with a bridge.
Colin Wellenkamp, executive director of the MRCTI, said $40 billion in the bipartisan Infrastructure Act is for bridges and “one of the priorities is resiliency.”
“There are needs here and there are resources that are being pushed out,” he says. “This is an opportunity to analyze risks and assess them.”
