A massive crane and a portion of the new Bay Bridge construction project came crashing down Thursday afternoon while it was being dismantled.
Thankfully, no one was hurt.
A Bay Bridge spokesman told NBC Bay Area that two 160 foot "ringer" cranes were working in tandem to lower a 258,000 pound piece of dismantled scaffolding when it slipped and caused one of the cranes to lose its center of gravity.
The huge chunk of metal landed on a barge below puncturing it clear through to the bay waters.
Roger Ladwig was at a nearby Marina and heard the crash.
"It sounded like a low flying plane. Just a grinding noise I wasn't sure what it was and it first it kind of shocked me," Ladwig said. "Next thing I know one of the cranes was already down and the scaffolding was perched up there suspended and collapsed onto the barge itself."
Each crane had two operators and an iron worker on the structure at the time of the accident. Eight other iron workers were on the scaffolding, according to the Bay Bridge spokesman. Again, no one was hurt.
This happened around 12:15 p.m.
A portion of the crane fell into the Bay, but most of it appeared to stay on the barge.
A Metropolitan Transportation Commission spokesman told Bay City News the crane was being used to remove temporary supports from under the deck of the new self-anchored suspension span when it tipped over.
MTC spokesman John Goodwin said the structure of the bridge was not damaged and is not expected to delay its scheduled Labor Day weekend opening.
From our helicopter over the scene, the red toppled crane covered two barge of the three barges involved in the dismantle project.
The second crane remained upright. The heavy section of scaffolding that came down appeared to land on a third barge which sat in the middle of the two cranes.
The dismantling work began four weeks ago and is scheduled to continue for months. The contractor and Coast Guard are trying to determine what went wrong.
The damaged crane was towed away from the scene late Thursday to a staging area near the bridge. The barge that held the scaffolding was also towed away. It was taken to a pier in Oakland.
The crane involved in Thursday's accident was operated by a company named American Fluor. NBC Bay Area's Stephen Stock did some digging into the company's background.
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