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, heralded as one of the most protected American bridges.

Whether or not 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.

Because it makes shipping more cost-effective, container ships have grown and grown in recent decades. Since the Key Bridge was built 48 years ago, cargo ships have more than quadrupled in tonnage, experts say. Without increased safety measures, the Key Bridge brought 1970s protective equipment to a 2020s catastrophe.

And ships keep growing. In Savannah, Georgia, the state is spending $189 million to increase the height of the Talmadge Memorial Bridge to welcome even bigger ships to its port. That bridge is currently 185 feet tall, about the same size as the Bay Bridge and the Key Bridge before its collapse, but its center span will be raised 20 feet.

“Nobody anticipated the size of ships that we have today,” former Maryland Transportation Secretary James Ports said. “They probably would’ve constructed a very different bridge had they been able to have a crystal ball.”

Ill-equipped for strike

Bridges that carry U.S. highways — as well as many state roads — are required to follow a code detailed in thousands of pages of guidelines from the American Association of State Highway and Transportation Officials (AASHTO), which has an entire section on vessel collision. But that wasn’t the case when many bridges were built; the guidebook added those specifications in the 1990s.

“The Key Bridge was designed to the standards at the time it was constructed in the early 1970s, which pre-dates any formal AASHTO guidance on vessel collision,” said Jason Hastings, the vice chair of AASHTO’s Committee on Bridges and Structures, in a statement to The Sun. “There have been significant changes in design specifications since that time, so a new bridge constructed today would be designed with different consideration given to vessel collision.”

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