NTSB: Maryland Highway Agency Failed to Prevent Baltimore Bridge Collapse

In a public briefing Thursday, the National Transportation Safety Board (NTSB) said that the Maryland Transportation Authority (MDTA) should have performed a standard engineering risk analysis on the Francis Scott Key Bridge, which collapsed in March 2024 after it was hit by the boxship Dali. The MDTA was on the national panel that came up with updated ship strike engineering standards in 1991, and it had three decades of well-informed advance notice to evaluate the Key Bridge, according to NTSB chair Jennifer Homendy.

MDTA couldn't even provide the underlying data to perform the analysis when NTSB asked, so NTSB worked with the National Highway Administration to gather the needed information and do the engineering work itself. NTSB's analysis found that the Francis Scott Key Bridge's risk of collapse from a ship strike was 30 times higher than recommended by existing federal guidance, and 15 times higher at the pier that the boxship Dali hit on March 26, 2024.

"We were very surprised that they were so high, almost 30 times greater than the threshold that AASHTO sets, and 15 times for pier 17 and pier 18. That was a surprise to all of us. But you know, it's something that MDTA could have known and should have known," Homendy said.

If MDTA had carried out the risk analysis anytime after 1991, the year that MDTA helped create the national standard, the state agency would have concluded that the bridge needed protection from a ship strike, Homendy said - and it could have prevented the collapse by making infrastructure improvements.

"There's no excuse," said Homendy.

She noted that as of late 2024, MDTA has still not performed the same risk analysis on the Chesapeake Bay Bridge, which was designed in the same era as the Francis Scott Key Bridge and experiences the same ship traffic, but at higher vessel speeds.

NTSB has issued an urgent recommendation to 30 bridge owners around the country to perform the standard ship strike risk analysis on 68 bridge spans, including both spans of the Chesapeake Bay Bridge.

"We are saying there is a safety deficiency here, a potential safety risk, and you need to take immediate action," said Homendy. "It shouldn't take an urgent safety recommendation to get action, and we expect that to be done now, and we'll follow up."

Maryland's transport agency had decades of advance notice. In addition to the 1991 AASHTO recommendation, which MDTA helped draft, a senior Maryland pilot raised concerns about the risk of an allision between a big ship and the Francis Scott Key Bridge at least as early as 2006 - and continued to discuss the matter in local safety meetings for years, according to detailed records uncovered by the Washington Post.

The documents also show that at the staff level, the Maryland Transportation Authority was aware that their bridge was "not designed to withstand collisions from large vessels," and that the cost of protecting it would be high.

In neighboring Delaware, a state agency has shown that safety upgrades are possible - and costly. Ten years ago, in 2015, Delaware's bridge transport authority set aside $2.5 million to design new protective dolphins for the Delaware Memorial Bridge to defend against ship strikes. The agency bundled the dolphin project into a large package of renovations, secured a permit from the Corps of Engineers, raised tolls on motorists, convinced two state governors to sign off on the cost, and issued bonds to raise funds. Construction started on the eight protective steel-and-rock dolphins last year, and should be done by the end of 2025.

NTSB will release its final report later this year, including the findings of its maritime investigative team on the factors aboard the Dali.