Engineers launch “urgent” safety assessment of U.S. bridges near ports

Engineers at Johns Hopkins University have begun an “urgent assessment” of the country’s bridges, particularly the larger ones near major ports of entry, saying they believe the chances are high for additional ships to hit U.S. bridges like the recent catastrophe in Baltimore.

The team plans to release preliminary results this summer, producing a quick result thanks to a National Science Foundation Rapid Response Research grant and the help of an “army” of students. Researchers will attempt to modernize risk prediction models, as the nature of shipping—and particularly the prominence of massive cargo vessels—has increased considerably in the decades since most of these bridges were built.

“We need to know now, not five or 10 years from now, whether there is an outsize risk to bridges across the country so that critical investments—which will take years—can begin immediately if they are needed,” team leader Michael Shields, a Johns Hopkins engineer specializing in risk assessment, said in a release. "The Key Bridge collapse was a wake-up call.” 

Disaster recovery workers are still hustling to clear the wreckage and re-open the main shipping channel at the Port of Baltimore after the M/V Dali containership collided with the Francis Scott key bridge on March 26, causing the structure to collapse, killing six people, and forcing the closure of the nearby ocean freight port.

The team hypothesizes that the risk of the Key Bridge collapse was underestimated and that the probability of another catastrophic collision in the United States is likely “much higher” than current design standards presume. “Clearly the risk to the Key Bridge was very different in 2024 than it was in 1977 when the bridge opened,” Shields said. “But we don’t currently understand that risk.” 

To find answers, the team will mine global shipping data, develop modern risk models, and then attempt to identify which critical U.S. bridges are vulnerable to a catastrophic ship collision. Using the shipping data, they will build models to determine the probability of a ship deviating from course and hitting a bridge in or around major ports.

“Preliminary findings already challenge prevailing assumptions,” team member Rachel Sangree, a structural engineer and former bridge inspector, said. “The U.S. has seen 17 incidents of major bridge collapse between 1960 and 2011, averaging one every three years. Between the exponential growth of mega freight ships and the surge in global shipping traffic, many of our bridges simply weren’t built to withstand the pressures of today’s maritime landscape.”