Exactly four weeks after the Francis Scott Key Bridge collapsed, salvage crews removed its biggest piece of debris to date, a section of truss weighing 560 tons, clearing the way to open the deepest and widest temporary channel by the end of this week.

The temporary channel will be 35 feet deep and 300 feet wide, with a vertical clearance of 214 feet, the fourth one to open since the freighter Dali struck one of the bridge footings in the early morning hours of March 26 and brought it down instantly. The wreckage has closed off the port to its usual shipping traffic.

Gov. Wes Moore confirmed the anticipated opening at a press conference Tuesday afternoon, calling it a “step on the journey.”

“Unified command began laying out buoys and lights to mark the fourth temporary channel with a controlling depth of 35 feet,” Moore said, flanked by Mayor Brandon Scott, Baltimore County Executive Johnny Olszewski, and officers from the U.S. Army Corps of Engineers, and Coast Guard. “That channel is scheduled to be available to transit later this week, weather permitting.”

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Although officials mentioned no specific day for the opening, the Coast Guard released a marine safety bulletin that stated passage through the channel will be allowed starting Thursday, until 6 a.m. on Monday or Tuesday, depending on weather conditions. No severe or unusual weather is predicted in the coming days, although winds will pick up Friday afternoon.

The bulletin also stated that vessels will be required to maintain speeds no faster than 5 knots. Only vessels with a displacement of less than 60,000 long tons will be allowed to pass.

“We need to make sure that our commercial movements do not slow our work as we’re still clearing the wreckage,” Moore said, emphasizing the salvage operation is still happening 24 hours a day, seven days a week. “[Crews] are literally pulling steel from the water with active vessels moving around them.”

The 35-foot channel will initially be opened for a short time, about four days, allowing departures for five of the seven cargo vessels that have been stranded in port since the bridge fell. Among them is a loaded vessel carrier, Carmen, which has been tied up in Dundalk.

The other four vessels expected to depart through the channel are the tanker Palanca Rio and the cargo ship Balsa 94, both moored along the piers on S. Clinton Street; the cargo ship Saimaagracht, also docked in Dundalk; and the bulk carrier Phatra Naree, which is docked closest to the salvage site at Hawkins Point.

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The bulk carriers Klara Oldendorff, docked at Consol Marine Terminal near the north entrance to the Baltimore Harbor Tunnel, and Jy River, in Curtis Bay, will remain until the full channel is open. Coal carriers are among the heaviest of commercial vessels and have the deepest drafts, even when empty.

At least three ships will also be allowed into the port, including a container barge, a small bulk carrier, and a ship carrying aluminum. Once those vessels make the transit, the 35-foot channel will be closed again for “roughly 10 days” said Coast Guard Rear Adm. Shannon Gilreath. “That will allow us to safely conduct the rigging we need to do onboard that large piece of the bridge that’s still on the bow of the Dali.”

Separating the bridge structure from the Dali is the key step in towing the ship and securing it to a dock. And removing the Dali is key to restoring the full channel, which engineers have promised by the end of May.

As of Tuesday, 2,000 tons of wreckage have been removed, Moore said. He also confirmed that 145 vessels have transited through the three temporary channels that have already been opened. Those channels, however, are shallow with depths between 10 and 20 feet, ample for only vessels such as tugboats and barges.

The addition of the 35-foot channel would mean about half the channel will be navigable. The full channel is about 700 feet wide.

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Critical to the opening was the removal of the 560-ton piece of debris, more than the weight of a fully loaded Boeing 747. The piece took two days to prepare and was lifted out of the water around midnight Tuesday. That followed the removal of a 460-ton piece of debris last week.

Salvage teams are now “laser focused” on the portion of the span on top of the Dali, said Col. Estee Pinchasin, commander of the Baltimore District of the Corps of Engineers.

“We’re going to work effectively and we’re going to work safe,” Moore said, “and we’re not going to choose between the two.”

Hugo Kugiya is a reporter for the Express Desk and has formerly reported for the Associated Press, Newsday, and the Seattle Times.

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