SAN FRANCISCO (CBS SF) - A crane being used for work on the new eastern span of the Bay Bridge toppled over Thursday after dropping a 129-ton piece of metal it was removing from underneath the bridge, a Metropolitan Transportation Commission spokesman said.
The barge-mounted crane was working in tandem with another crane to lower a section of the bridge’s temporary support structure via a large basket onto the barge near the tower under the deck of the new self-anchored suspension span, MTC spokesman John Goodwin said.
For reasons that have yet to be determined, at 12:15 p.m., the 258,000-pound temporary structure fell out of the basket and onto the empty barge below, causing the crane and its 168-foot boom to lose its center of gravity and also topple over, Goodwin said.
The temporary steel structure punctured the barge but did not sink it. There were four people conducting the work—two crane operators and two ironworkers—but no one was injured in the incident, according to Goodwin.
“This has been a remarkable project for the safety of the workers,” he said. “We’re very pleased that nobody was injured here.”
He said the fallen crane did not damage the structure of the bridge and was not expected to delay its scheduled Labor Day weekend opening.
Roger Ludwig, boat owner at Treasure Isle Marina, described what he saw to KCBS. “I saw the scaffolding collapse. I heard the sound, I turned around and by the time I turned around, the crane was down,” he said. “What I saw was the scaffolding suspended and then just fall onto the barge.”
Ludwig said crews have been doing similar work for weeks. “What they do is they have two cranes and they lift up a carrier underneath the scaffolding. They attach it to the scaffolding, the falsework. Then they cut the piece they want and then they lower it down to the barge and haul it away. They were cutting it and the next thing I know, all hell broke loose.”
The 99-by-88-foot barge is disabled and will have to be towed away, but remained under the bridge as of late Thursday afternoon, Goodwin said.
The U.S. Coast Guard responded to the incident with a boat and helicopter to make sure there was no one in the water, Coast Guard Lt. Erin Gilson said.
A Coast Guard boat was still patrolling the area Thursday afternoon to enforce a safety zone around the barge, Gilson said.
Bay Bridge spokesman Andrew Gordon said the crane did not fall into the water, and that Caltrans is waiting to hear from its contractor about what went wrong.
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