As ships grow and seas rise, can Baltimore's port use new bridge to raise the roof?

Building bridges to last a century requires educated guesswork. For example, decades from now, vehicular traffic patterns could look much different, noted Norma Jean Mattei, a University of New Orleans engineering professor and member of the White House’s National Infrastructure Advisory Council. The Bay waters are no different.

“The world gets fuzzier the further out you go,” she said, “and bridges are one of those pieces of infrastructure that we design for longer life.”

East Coast bridges grow

In a way, bridge height is simply a multibillion-dollar-industry version of keeping up with the Joneses. When recently discussing the possibility of replacing a bridge in Savannah, Georgia, with a taller one, local officials there referenced the high vertical clearances of bridges leading to New York/New Jersey, a competing port.

The Georgia Department of Transportation is looking to increase the height of that Savannah span, the Talmadge Memorial Bridge, which is 185 feet tall — the same as Maryland’s Bay Bridge.

“As the fastest-growing port in the nation, the Port of Savannah is a significant economic engine for the Savannah region, Georgia, and the rest of the Southeast,” a spokesperson for Georgia’s transportation department said in a statement. “Potentially stifling future growth, however, is the Port’s accessibility to larger ships.”

Georgia also is considering replacing the bridge — which opened only 33 years ago — with a span that has 230 feet of vertical clearance.

A neighbor to the north of Baltimore already has changed a bridge’s height. The Port Authority of New York and New Jersey increased the clearance of the Bayonne Bridge from 150 feet to 215 feet — a project that cost $1.7 billion.

“We raised the Bayonne Bridge in 2019 knowing that container ships were only growing bigger and demand for goods was only getting stronger,” port director Bethan Rooney said in a statement. “It paid off soon after, when the pandemic drove cargo volumes to numbers we weren’t expecting to see for another 10 years.”

Another New York-area bridge has even higher clearance: Big ships can easily fit under the 228 feet afforded by the Verrazano-Narrows Bridge. The 1,200-foot container vessels that call on New York typically have an air draft of about 175 feet to 195 feet, said James Mercante, president of New York’s Board of Commissioners of Pilots.

Cruise ships can come in even higher. The MSC Meraviglia, which sails under the Verrazzano, is 214 feet tall, according to the cruise line.

How tall the new Key Bridge will be remains undetermined, but one potential builder suggested a height of 213 feet in a May news release.

The Association of Maryland Pilots also might have hinted at the measurement its members prefer. The pilots, who guide large ships in Maryland waters, declined to comment for this article. But a representative discussed the possible height of a replacement Bay Bridge during a 2023 meeting of the Baltimore Harbor Safety and Coordination Committee — a joint industry-government advisory panel. Minutes from the meeting said pilots “have recommended a minimum bridge height of 228 ft, but preferably higher.”

Whatever height is chosen would not alter shipping traffic into Baltimore immediately, since the Bay Bridge remains 185 feet tall. Increasing the current Bay Bridge’s height would not be logical nor feasible, given its age. But “those bridges are basically coming to end of life, regardless,” said Wiedefeld, the transportation secretary.

The older of the two Bay Bridge spans has about 15 to 20 years left, he said. So, it’s possible that the Chesapeake Bay will see two new bridges in the coming decades; in doing so, the corridor’s ceiling might be altered for the next century.