Golden Gate Bridge, other Bay Area spans at unknown risk of collapse from vessel collision, NTSB report says
A new report compiled after the Francis Scott Key Bridge collapse in Baltimore shows that San Francisco's Golden Gate Bridge and four other Bay Area spans may be vulnerable to collapse from a ship strike.
The report from the National Transportation Safety Board released Thursday said 68 bridges across 19 states are at unknown risk for a collapse in a vessel collision and urged bridge owners and officials to conduct a vulnerability study to determine the risk.
In the Bay Area, aside from the Golden Gate Bridge, other bridges listed as having unknown vulnerability of collapse from a vessel collision are the Antioch Bridge, the Benicia-Martinez Bridge, the Carquinez Bridge, and the San Mateo-Hayward Bridge.
Both the Antioch Bridge and the San Mateo-Hayward Bridge were given a less severe warning than the other spans. The San Francisco-Oakland Bay Bridge was not among those listed as the NTSB noted it already has active or near-term plans to assess its vulnerability to collapse.
On November 7, 2007, a fender of one of the Bay Bridge towers was struck by the Cosco Busan container ship, creating a gash in the ship's hull and the spillage of over 53,000 gallons of fuel oil into San Francisco Bay. The fender was damaged but the bridge remained intact; however, the oil spill cleanup and habitat restoration projects cost more than $70 million. One of the fenders was again struck by a vessel in 2013, but the fender sustained minor damage in that instance as well.
The Bay Area Toll Authority was among the first bridge owners to be named by the NTSB, along with Caltrans and the Golden Gate Bridge, Highway and Transportation District for needing an immediate vulnerability assessment.
John Goodwin with the Metropolitan Transportation Commission, which is aligned with the Bay Area Toll Authority, said it is unclear when the last vulnerability assessment was done on Bay Area bridges, but one is already underway.
"Ships are bigger than they ever have been, which is a really important factor," said Goodwin.
The Golden Gate Bridge, Highway, and Transportation District released a statement following the NTSB report stating that it was "in full compliance with all state and federal regulations, including federal bridge inspection and evaluation requirements."
The response noted that "a large vessel would run aground before colliding with the pier" at the North Tower, while the South Tower "is protected by a concrete fender ring that extends into the seabed...and is 27 feet thick at its base and 10 feet thick at sea level, providing significant protection against collisions."
On March 26, 2024, the 984-foot containership Dali was headed out of Baltimore Harbor when it lost power and drifted in a pier supporting the central truss spans of the Francis Scott Key Bridge, causing it to collapse. Six construction workers on the bridge were killed and another was injured, as well as one person onboard the vessel.
The NTSB report indicated the Key Bridge was nearly 30 times above the acceptable risk threshold for critical or essential bridges, according to guidance established by the American Association of State Highway and Transportation Officials. The report said the 68 other bridges it identified, like the Key Bridge frequented by ocean-going vessels, were all built before the AASHTO guidance was issued in 1991.
"Today's report does not suggest that the 68 bridges are certain to collapse," read a press release Thursday from the NTSB. "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."
Other bridges listed in the report include the Coronado Bridge in San Diego, New York's Brooklyn Bridge and Manhattan Bridge, the Chicago Skyway Calumet River Bridge in Illinois, the Delaware River Turnpike Bridge in Pennsylvania, and the Lewis and Clark Bridge in Washington.
At the time AASHTO established its guidance, which followed the 1980 Sunshine Skyway Bridge collapse in Florida, it also recommended that all bridge owners conduct vulnerability assessments to evaluate the risk of collapse from a ship strike. The organization reiterated the recommendation in 2009, the NTSB said.
