The Claiborne Pell Newport Bridge is among 68 bridges nationwide that need urgent evaluation for their risk of catastrophic collapse from vessel strikes, according to a new National Transportation Safety Board report.
The NTSB identifies the Newport Bridge, built in 1969 and owned by the Rhode Island Turnpike and Bridge Authority, as having an “unknown level of risk” because it was constructed before modern vessel collision design standards were established.
The recommendation comes as part of the NTSB’s ongoing investigation into the March 26, 2024, collapse of the Francis Scott Key Bridge in Baltimore after it was struck by the containership Dali.
“The 30 owners of 68 bridges over navigable waterways frequented by ocean-going vessels are likely unaware of their bridges’ risk of catastrophic collapse from a vessel collision and the potential need to implement countermeasures to reduce the bridges’ vulnerability,” the NTSB states in its report.
The NTSB’s investigation reveals the Key Bridge was almost 30 times above the acceptable risk threshold for critical bridges according to standards established by the American Association of State Highway and Transportation Officials (AASHTO).
“Had the Maryland Transportation Authority conducted a vulnerability assessment of the Francis Scott Key Bridge based on recent vessel traffic, as recommended by the 1991 and 2009 AASHTO Guide Specifications, the MDTA would have been aware that this critical/essential bridge was above the AASHTO threshold of risk for catastrophic collapse from a vessel collision when the Dali collision occurred,” the report concludes.
The NTSB classifies the Newport Pell Bridge as a “typical” bridge rather than “critical/essential,” which means it has a higher acceptable risk threshold than bridges serving as important links in the Strategic Highway Network.
The NTSB recommends the Rhode Island Turnpike and Bridge Authority calculate the “annual frequency of collapse” for the Newport Bridge using AASHTO’s Method II vulnerability assessment calculation. This mathematical risk model considers bridge geometry, pier protection, vessel traffic characteristics, waterway features, and other factors.
If the assessment shows the bridge exceeds AASHTO’s acceptable risk threshold, the authority must develop and implement a comprehensive risk reduction plan with short and long-term strategies to reduce collapse probability.
The NTSB is also recommending the Federal Highway Administration, U.S. Coast Guard, and U.S. Army Corps of Engineers establish an interdisciplinary team to provide guidance to bridge owners on evaluating and reducing vessel collision risks.
“The process of calculating vulnerability assessments enables owners to make informed decisions to manage their assets, identify their bridges that may be susceptible to damage from a vessel collision, and appraise and prioritize vessel collision protection projects alongside other projects addressing highway asset needs and risks,” the NTSB explains.
The Newport Bridge is one of 68 bridges across 19 states that meet the NTSB’s criteria for needing assessment: built before 1996 (before AASHTO guidelines were widely implemented), having a vertical clearance of at least 80 feet, having piers in the water, and experiencing significant ocean-going vessel traffic.
The NTSB emphasizes that inclusion on the list doesn’t mean these bridges are certain to collapse, only that their risk level is currently unknown and needs evaluation.
Modern vessels like the Dali, which struck the Key Bridge, highlight potential vulnerabilities in older bridge designs. The Dali is a 984-foot-long containership with significantly greater size and weight than vessels common when many of these bridges were designed.
The Key Bridge collapse occurred when the Dali experienced a loss of electrical power and propulsion while transiting out of Baltimore Harbor. It struck Pier 17, the southern pier supporting the central span of the bridge, causing a catastrophic collapse that killed six construction workers.
The NTSB’s investigation found that while the Key Bridge had physical protection systems including four 28-foot-diameter dolphin structures with rubber fenders and crushable concrete and timber fendering systems, these protections proved inadequate against a modern vessel like the Dali.
Bridge vulnerability assessments consider multiple factors including vessel frequency distribution, probability of vessels going off course, probability of hitting bridge piers, probability of bridge collapse after collision, and effectiveness of protection structures.
The NTSB notes that engineering and shipping advances—such as the 2016 Panama Canal expansion—have led to larger vessels and increased traffic volume to many U.S. ports, potentially increasing risks to bridges designed before these developments.
For the Newport Bridge and others on the list, the NTSB’s urgent recommendation requires bridge owners to inform the safety board whether their bridges exceed the AASHTO risk threshold.
The NTSB’s full Marine Investigation Report, including detailed vulnerability assessment methodologies and the complete list of bridges requiring evaluation, is available online.
