The National Transportation Safety Board (NTSB) has urged 30 bridge owners across 19 states to conduct vulnerability assessments following its investigation into the collapse of the Francis Scott Key Bridge in Baltimore.
The bridge collapsed on March 26, 2024, after being struck by the cargo vessel Dali, highlighting concerns over the structural resilience of older bridges.
The NTSB found the Key Bridge’s collapse risk was nearly 30 times above the acceptable threshold set by the American Association of State Highway and Transportation Officials (AASHTO).
As part of its investigation, the NTSB identified 68 bridges built before modern AASHTO guidelines were established that lack updated vulnerability assessments. While the report does not indicate these bridges are at immediate risk, it recommends owners evaluate their structural integrity using AASHTO’s Method II calculation and develop risk reduction plans if necessary.
AASHTO first introduced vulnerability assessments in 1991, following the Sunshine Skyway Bridge collapse in Florida, according to a report from NTSB. The Federal Highway Administration (FHWA) later mandated that new bridges be designed to minimize collapse risks from vessel collisions, a requirement the Key Bridge predated.
The NTSB said in a report that if the Maryland Transportation Authority had conducted a recent vulnerability assessment, officials would have recognized the Key Bridge’s heightened risk and taken steps to mitigate potential dangers.
Additionally, the NTSB has recommended that FHWA, the U.S. Coast Guard and the U.S. Army Corps of Engineers form a task force to assist bridge owners in assessing and reducing risk through infrastructure improvements or operational changes.
Source: National Transportation Safety Board, CBS News
