U.s.-required inspections don’t test for ship strikes
BALTIMORE » When the Francis Scott Key Bridge was inspected in May 2021, it earned high marks:
• Its railings and guardrails met modern standards.
• Its foundations were “stable” and didn’t show signs of erosion at the riverbed.
• The protection around its piers was “functioning,” the best grade in that category.
It wasn’t, however, assessed for its ability to withstand a collision from a vessel.
A collision came, though. In the early hours of March 26, a massive cargo ship — much larger than the average ship when the bridge was built in 1976 — crashed into one of the bridge’s vital supports. The impact sent those railings, guardrails and roughly 50,000 tons of steel and concrete tumbling into the Patapsco River.
The catastrophe killed six men fixing potholes on the bridge, launched arduous efforts to clean up what could be the costliest maritime accident ever and prompted an already litigious fight over who will foot the bill.
The National Transportation and Safety Board is investigating the incident with a focus on the ship’s electrical system and the FBI is conducting a criminal probe.
How they work
Bridge inspections are typically completed by the bridge owner or one of its contractors, then the owner provides the data to the federal government. The Key Bridge’s 2021 inspection is the most recent included in the Federal Highway Administration’s National Bridge Inventory.
Although protection from a ship strike is considered when any bridge is constructed today, there are no federal statutes, regulations or policies that require existing bridges be evaluated for the possibility of a vessel collision. Whether to do so is left to the judgment of each bridge’s owner, the Federal Highway Administration said.
Some bridge owners elsewhere — including ones in California, Delaware and New York — say they already do that.
Asked whether the Key Bridge or the Chesapeake Bay Bridge were ever evaluated for vessel collision, the bridges’ owner, the Maryland Transportation Authority, offered a statement instead of an answer, “Our asset management program continually prioritizes asset needs based on age, condition, criticality and risk. We will continue to evaluate the condition of bridges as well as their risks as part of our well-established nationally recognized programs.”
The authority said that “with the Key Bridge incident in mind, there has been a renewed focus on pier protection” of its bridges and it will consider any recommendations made by the NTSB.
But that agency’s final report could take up to two years. NTSB Chair Jennifer Homendy told members of Congress earlier this month that evaluating “pier protection” is something that bridge owners can do now.
“There’s still action that needs to occur to look, frankly, at how shipping has changed over the years, how transportation has changed in our waterways, the types of vessels that we are seeing, the types of container ships that we are seeing, the volume of traffic, and looking at bridge designs,” she said.
“If I were a state and the Department of Transportation, that’s what I would be looking at now — are these bridges protected for the types of traffic that is going through now?” Homendy told a Senate committee.
‘Accidents do happen’
Bridge collapse due to vessel collision is rare and it took a nightmarish scenario to bring about disaster in Baltimore. The Dali, a cargo ship the size of the Eiffel Tower, appeared to lose power at the most inopportune moment, causing an unthinkable calamity.
Only, it wasn’t entirely unthinkable to some. In 2016, Michael A. Knott, a Moffat Nichol engineer with expertise in bridge strikes, presented to a group of engineers in Baltimore on the topic of “Ship Barge Collisions with Highway Bridges.” Referencing 35 instances of major bridge collapses worldwide since 1960, Knott explained that vessels run into trouble for several reasons, including engine or steering failure.
“Accidents do happen,” reads text from his slide show. “It’s Only A Matter of Time.”
Knott, who presented to Maryland’s section of the American Society of Civil Engineers, wasn’t specifically referencing the Key Bridge, although his slide show did note a 1980 incident in which a much smaller ship hit the bridge.
But bridges with piers in navigable waterways are at risk of collision, even if it’s to a small degree. For decades, the Key Bridge and its southern counterpart, the Bay Bridge, had avoided disaster despite thousands of ocean liners passing under them annually.
As long as everything goes as planned, there is no damage done. But things go wrong:
• In 2022, a Maryland pilot onboard the Ever Forward was distracted by his cellphone and the cargo ship missed a turn in a 50foot deep channel, running aground in the bay.
• At least 42 vessels have experienced propulsion, steering or power problems in Maryland waters since the start of 2021, according to an analysis of U.S. Coast Guard reports.
Condition vs. strength
When a vessel goes astray, it’s up to safety precautions, like fenders that protect piers or tugboats that steady cargo ships, to prevent catastrophe.
Tugboats have not been required to assist ships under the Key Bridge. And although the bridge’s “pier abutment protection” received high marks during its 2021 inspection, that rating determined merely the “condition” of the protective system — not its strength.
It’s similar to inspecting an original Ford Fiesta; despite not having an airbag, its existing safety features could be in working condition, even if they’d be considered inadequate for today’s world.
The Key Bridge had four small concrete “dolphins” — artificial islands meant to deflect vessels from bridge supports — along its channel as buffers for its two biggest support columns.
They paled in comparison to protective systems of modern bridges. Auburn University engineer Andrzej Nowak likened them to “kids’ toys.”
Still, the Key Bridge’s pier protection received the same score (“in place; functioning”) as the Sunshine Skyway Bridge in Tampa, Fla., heralded as one of the most protected American bridges.
Whether a fortified system could have withstood the gigantic force generated by the 984-foot, 248-million pound behemoth traveling 8 mph is debated by engineers. When asked if Tampa’s Sunshine Skyway — which was knocked down in 1980, then rebuilt with significant protections — could have withstood the Dali’s strike, the Florida Department of Transportation said it would be “unable to make a comparison,” given the multiple factors.