Following the collapse of the Francis Scott Key Bridge in Baltimore that launched a monthslong cleanup and recovery effort, the federal government is now examining dozens of large bridges across the county for resiliency.
According to Scripps News, the Key Bridge that plummeted into the Patapsco River in March was only the most recent major collapse, with a recent U.S. Coast Guard report of maritime incidents showing a vessel has run into part of a bridge in the U.S. at least 650 times since 2019.
Many of those bridges soar across the Mississippi River, a major shipping thoroughfare.
One is example is the Old Highway 80 Railroad Bridge in Vicksburg, Miss., which is struck by barges sometimes multiple times a day according to Herman Smith, superintendent of the Vicksburg Bridge Commission of Warren County.
"It is the most-hit bridge on the river system," he said to Scripps.
A sharp bend in the river and swift currents can make the stretch of the Mississippi, near the bridge, a challenge for boat captains trying to guide barges, tethered together, between two piers.
"You don't drive a boat like you do a car with a trailer," said Smith. "Here, they can't do that unless the water is really, really, really slow."
One of the most damaged pillars has been hit more than 200 times, earning it the nickname ‘Scar’.
An up-close view shows inches of concrete scraped away by barges over the years, exposing steel rebar installed when the bridge was built almost 100 years ago. Even though the bridge is frequently struck by vessels, Smith said he does not believe any have been large enough to take out a pillar with how thick the concrete is.
But even small vessels can threaten large bridges according to the U.S. Coast Guard’s report.
In 2018, a crane barge crashed into the deck of the Sunshine Bridge over the Mississippi River in Convent, La. and was catastrophically damaged.
The bridge in Vicksburg and the Key Bridge were built decades before national design standards spelled out how to build bridges capable of absorbing ship and barge strikes.
Keeping standards up to date and relevant to all bridges is difficult, said Jason Hastings, vice chair of the Committee on Bridges and Structures at the American Association of State Highway and Transportation Officials (AASHTO) to Scripps.
"I think there is a big issue with the constant change in the size of the ships as they continue to grow," said Hastings. "By the time that we are able to collect the data and get those standards passed, ships have grown beyond that."
AASHTO did not begin setting vessel collision standards until 1991, a decade after a cargo ship brought down the Sunshine Skyway Bridge in Tampa, killing 35 people.
Those standards, later adopted by the Federal Highway Administration, are mandatory in the design of new bridges only.
What remains unclear for the Vicksburg bridge, and many other older bridges around the country, is exactly how much force they can safely withstand from a wayward ship or barge.
Source: Scripps News, USA Today
