Surprise! Key Bridge Rebuild Costs Skyrocket

Balmer Sun, Key Bridge: Rising costs, wrong assumptions led rebuild cost to balloon, MDTA says

The Maryland Transportation Authority on Tuesday attributed the increase in costs to replace the Key Bridge — which rose this week to $5.2 billion from as low as $1.7 billion — to a volatile economy. However, the MDTA also insists the 2024 estimates were just preliminary and had to be calculated for Maryland to qualify for emergency relief from the federal government.MDTA Executive Director Bruce Gartner told The Baltimore Sun that original estimates to rebuild the bridge, which collapsed in March 2024 after a container ship rammed into it, were calculated without “any engineering or design.” Now the MDTA is approaching “70% design,” he said, thanks to “numerous…engineering calculations on bridge standards for vessel protection” that have provided his department with a clearer picture of “the conditions in the riverbed.”

“All we could do in those initial days was look at other bridges of a similar size and then work — since bringing a design builder on board, a progressive design builder on board — to further that engineering along to where we are now,” Gartner said in a phone interview with The Baltimore Sun. Gartner added that Maryland’s progress in rebuilding the bridge outpaces other states in similar situations.

“There’s bridges out there over the Mobile River in Alabama, the Brent Spence between Kentucky and Ohio — big bridge projects that are experiencing similar things, but they’ve taken years and years to design,” he said. “We’ve designed over the last 14 months.”As work progressed, it became clear the bridge needed a redesign, he said, such as a main span about 300 feet longer than anticipated to accommodate federal highway guidelines and larger vessels.

“We were not expecting it to have to be that wide,” Gartner said. That, in turn, meant bridge towers had to be more than 100 feet taller than expected, adding to the project time and cost. A vessel protection feature, more than a football field-sized system of fenders, also proved more complex and expensive than expected, he said.

Also at the Sun, Key Bridge rebuild: Maryland lawmakers slam soaring costs