The gap under the Bayonne Bridge enables larger container ships to reach Newark Bay.

Authorities on Tuesday removed the height restriction on certain ships going under the Bayonne Bridge in the Port of New York and New Jersey — a change they said would make scheduling ships easier and enable them to carry slightly more cargo — as the project to raise the bridge advances.

The Port Authority of New York and New Jersey said there would no longer be an air draft height limit of 149 feet on ships smaller than 9,800 TEU, the size of the largest ship that to date has gone under the bridge. Beth Rooney, assistant director of the port authority’s port division, said the change would enable the ships to carry more containers through better “utilization of the vessel.”

The removal of the restriction comes as the port gets closer to completing a $1.3 billion project to raise the elevation of the road bridge from 151 feet to 215 feet, so that ships up to 18,000 TEU can get to all of the port’s four main terminals. At present, mega-ships can only get to one terminal — GCT Bayonne — that is reachable without going under the bridge. The bridge is too low to enable large ships to pass under and get to the other three terminals.

The port, until Tuesday, required ships to have air draft of two feet under the bridge's former height of 151 feet.

Ports along the East Coast are monitoring the elevation project because more large vessels are expected to come through the Panama Canal and stop at other ports along the coast if they can get into the port of New York and New Jersey.

In effect, the height limit change announced Tuesday means that all ships below the maximum vessel size to go under the bridge — 9,800 TEU — would no longer have to worry about scheduling arrival or their departure in line with the tide to ensure the ship could fit under the bridge, said Rooney. That makes scheduling ships to come in and out of the port significantly easier, she said.

Likewise, ships would no longer have to leave cargo behind on the dock in some instances, or add or remove ballast, in order to pass under the bridge, she said. In some cases, that has been needed to fit below the bridge and in other cases it has been needed to ensure there is enough water below the ship, she said.

“If you are looking to meet a tidal window in order to squeeze under the bridge you are going to potentially leave cargo or empty containers, you leave them on the dock and you cut and run,” Rooney said. That strategy will no longer be required, she said.

As part of the elevation project, the port has built a second roadway 64 feet above the first, and is now in the process of removing the lower road deck. The removal of about half the deck, leaving a large gap in the middle, prompted authorities to lift the height restriction after discussions between the port and the Bayonne Bridge Navigational Clearance Bridge Team, which includes the US Coast Guard and port pilots.

The port authority has said the elevated bridge will be open by the end of the year, but they hope it will be open sooner than that.

“This is a first step that will make it more efficient and economical for vessels to reach our port terminals until the Bayonne Bridge’s navigational impediment is completely removed,” said Port Department Director Molly Campbell. “We’re pleased with the progress on that project and we expect to soon be welcoming 14,000-TEU vessels to our port terminals.”

Contact Hugh R. Morley at Hugh.Morley@ihsmarkit.com and follow him on Twitter: @HughRMorley_JOC.

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