MaineDOT will begin demolishing the compromised part of a bridge in Old Town next Tuesday.

It’s the portion of a new bridge that collapsed while under construction back in August.

Three people were injured when the collapse occurred while crews were pouring concrete on the new span.

Watch a video of the collapse here.

DOT says there’ll be intermittent closures of the adjacent temporary bridge while crews carefully remove the collapsed span.

“The work will include crews carefully separating the span from the pier and abutment, reducing it into smaller pieces, and lifting those pieces from the river for processing on land,” MaineDOT said in a news release. “This work will proceed slowly and carefully to protect workers and the public while minimizing damage to the pier and abutment.”

DOT says the collapse likely involved buckling of a girder, followed by an immediate cascading failure of the adjacent girders.

The agency says determining exactly how the beams failed is part of an investigation into the collapse, and will require additional engineering analysis.

The Llewellyn Estes Bridge consists of two bridges carrying Stillwater Avenue over two channels of the Stillwater River in Old Town.

Three workers were injured during the collapse, including one suffering a broken ankle, and two sustaining minor injuries.