'Risk Of Collapse' Evaluation Ordered For 7 California Bridges

CALIFORNIA — As the National Transportation Safety Board continues its investigation into the deadly collapse of the Francis Scott Key Bridge in Maryland, the safety administration has identified numerous bridges that are also at risk of collapse should a vessel collide with them.

As a result of the investigation, the NTSB is recommending that 68 bridges — including seven in California — undergo a vulnerability assessment to determine the risk of collapse.

The NTSB this week released a report on the March 2024 Maryland incident that documented dozens of other bridges across the nation they say have "unknown levels of risk of collapse" from vessel collisions.

In California, seven bridges are recommended to undergo a risk assessment:

• Golden Gate Bridge
• Richmond-San Rafael Bridge
• Carquinez Bridge
• Benicia-Martinez Bridge
• Antioch Bridge
• San Mateo-Hayward Bridge
• Coronado Bridge

All are deemed "critical/essential" bridges, except for the Antioch and San Mateo-Hayward bridges, which are listed as "typical."

The oldest and most famous of all these bridges is the Golden Gate Bridge, an internationally beloved bridge that serves as one of California's most iconic landmarks. The newest is the Antioch Bridge, which was built in 1978.

The NTSB is recommending the bridge owners — which include the Bay Area Toll Authority, Caltrans, and the Golden Gate Bridge Highway and Transportation District — calculate the annual frequency of collapse for the structures using the Method II calculation from the American Association of State Highway and Transportation Officials.

If a bridge exceeds that risk threshold, it is considered high risk, according to NTSB. The owners must inform the NTSB whether the probability of collapse is above the threshold.

"Today’s report does not suggest that the 68 bridges are certain to collapse. The NTSB is recommending that these 30 bridge owners evaluate whether the bridges are above the AASHTO acceptable level of risk. The NTSB recommended that bridge owners develop and implement a comprehensive risk reduction plan, if the calculations indicate a bridge has a risk level above the AASHTO threshold," the NTSB said.

A date by which the assessments must be complete was not immediately clear.

— Patch staffer Max Bennett contributed to this report.