The section of sheet piling that toppled over this week at a construction site near the 17th Street Canal had been hanging from the top of an excavator and slipped out of its grasp, an official with the U.S. Army Corps of Engineers said Friday.

The 80-foot-long, 9,000-pound section of piling, part of a temporary wall known as a cofferdam, had not yet been driven into the ground when it fell about noon on Monday, Corps spokesman Ricky Boyett said.

He added that, so far, no evidence has turned up of any broader problems with materials or engineering at the site.

The accident set off a chain reaction that knocked over a section of the cofferdam wall, which was being used to block off a portion of the canal’s mouth so it could be drained and used as a staging area for equipment needed to continue construction of a permanent pump station at the site.

That area is being used during construction only and is not a part of the upgrades to the canal itself.

No one was injured in the incident.

The Corps and PCCP Constructors, the joint venture working on the project, stopped work on the project to review the accident and what caused it. As a result of that investigation, future piles being driven on the site will be secured with a cable attached to a crane until they are driven deep enough to prevent similar incidents, Boyett said.

The Corps is still evaluating the rest of the wall to determine whether any damage was caused by the collapse.

The accident is not expected to set back the project, which is on track for completion by the 2017 hurricane season, and it will not increase the amount the federal government is paying for the project, Boyett said.

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