Explosives detonated in partial demolition of large span of Baltimore's collapsed Key Bridge

Crews used explosives in the partial demolition of the largest remaining steel span of Baltimore's collapsed Francis Scott Key Bridge Monday evening.

The loud explosion, captured by a News4 camera about a half mile away, broke apart the span, knocking a large, mangled portion of the steel bridge off the bow of the container ship Dali. That portion of the bridge remains visible above the Patapsco River.

Some steel beams remain embedded in the bow, and part of the roadway is still on the Dali. Those will be removed after the Dali is towed back to the Port of Baltimore

“That’s an important milestone for us, because it will allow us, now, over the next 48 hours, to assess the Dali and safely move it to a safer part of the port, and for us to go back in now and pick up the remaining roadway and steel truss at the bottom of the channel to meet our commitment of fully opening this channel by the end of the month,” U.S. Army Corps of Engineers Lt. Gen. Scott Spellmon said.

Crews plan to use hydraulic grabbers to lift the resulting sections of steel onto barges.

The demolition was postponed over the weekend because of weather conditions, officials said.

Crews prepared for weeks break down the span, which was an estimated 500 feet (152 meters) long and weighed up to 600 tons (544 metric tons).

It landed on the Dali’s bow after the ship lost power and crashed into one of the bridge’s support columns shortly after leaving Baltimore early March 26. Since then, the ship has been stuck amidst the wreckage and Baltimore’s busy port has been closed to most maritime traffic.

Officials said lightning in the area and rising tides Sunday prompted them to reschedule.

Six members of a roadwork crew plunged to their deaths in the collapse. The last of their bodies was recovered from the underwater wreckage last week. All the victims were Latino immigrants who came to the U.S. for job opportunities. They were filling potholes on an overnight shift when the bridge was destroyed.

The removal of the bridge allows the Dali to be refloated and guided back into the Port of Baltimore. Once the ship is removed, maritime traffic can begin returning to normal, which will provide relief for thousands of longshoremen, truckers and small business owners who have seen their jobs impacted by the closure.

The Dali’s 21-member crew sheltered "in a designated safe place" onboard the ship while the explosives were detonated, said William Marks, a spokesperson for the crew.

Officials said the controlled demolition was the safest and most efficient way to remove steel under a high level of pressure and tension.

In a videographic released last week, authorities said engineers used precision cuts to control how the trusses would break down. They said the method allows for “surgical precision” and the steel structure will be “thrust away from the Dali” when the explosives send it tumbling into the water.

Officials said three or four tugboats will be used to guide the Dali to a nearby terminal in the Port of Baltimore. It will likely remain there for a few weeks and undergo temporary repairs before being moved to a shipyard for more substantial repairs.

The Dali crew members haven’t been allowed to leave the vessel since the disaster. Officials said they have been busy maintaining the ship and assisting investigators. Of the crew members, 20 are from India and one is Sri Lankan.

The National Transportation Safety Board and the FBI are conducting investigations into the bridge collapse.

Danish shipping giant Maersk chartered the Dali for a planned trip from Baltimore to Sri Lanka, but the ship didn’t get far. Its crew sent a mayday call saying they had lost power and had no control of the steering system. Minutes later, the ship rammed into the bridge.

Officials have said the safety board investigation will focus on the ship’s electrical system.