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Video: Salvors Will Cut Baltimore Bridge Span Into Pieces With Explosives

Dali bridge deconstruction with explosives
Courtesy USACEq

Published May 9, 2024 6:42 PM by The Maritime Executive

On Wednesday, the unified command for the salvage of the boxship Dali released the first detailed description of its plan to remove a multi-thousand-tonne bridge truss from the ship's foredeck. Specialists are cutting precise holes in the bridge's girders and packing them with explosive charges, then wrapping the charges with a mat material. When all is ready and the button is pushed, the truss will be cut into a dozen pieces and will collapse into the water, falling safely away from the ship.

When the Dali hit and collapsed the Francis Scott Key Bridge in late March, the bridge's truss, deck and part of a support column came down on the ship's bow - pinning it to the muddy bottom of the channel. Almost all of this debris has been painstakingly cleared away, except for the largest section of the truss, which the team has labeled "section four." An animation released by the U.S. Army Corps of Engineers' Baltimore branch shows how the explosive charges will cut up this final section, without risking salvage personnel or lifting equipment during the removal. 

The unified command has previously hinted at a simultaneous cutting method that would free up section four, but only recently confirmed that the team would use explosive charges. The process will be dramatic, but it will not be a Hollywood-grade fireball, the USACE said. The detonations will sound more like a string of fireworks, and there will be no vast bursts of flame. The crew is expected to stay safely aboard the ship throughout the process, a Coast Guard spokesman told local media earlier this week. 

While waiting for the refloat operation to be finished, the Captain of the Port for Maryland has reopened the "limited access channel" next to Dali for commercially essential shipping. The waterway reopened Wednesday at 1900 and will remain open until 0600 on Friday. This time, the allowable draft has been increased to 45 feet from the previous restriction of 35 feet. This is nearly back to the normal depth of the federal channel, 50 feet - though the waterway is still much narrower because of the need to navigate around Dali and the truss section. A two-tug escort is required for all traffic. After the channel closes Friday, it will be shut until May 14 to allow salvors to continue their work.