The under-construction Old Town bridge spanning the Stillwater River will now use conventional steel girders.
That comes after a portion of the new Llewellyn Estes Bridge collapsed on the afternoon of Aug. 14, injuring one person.
The Stillwater Avenue bridge is being constructed by Woolwich-based Reed and Reed Inc. using Winterport-based engineering firm Basalt International’s fiber-reinforced polymer and girders using technology, known as GBeams, developed by the University of Maine’s Advance Structures and Composites Center.
Basalt International has heralded the polymer, which was developed in Maine, as a “miracle material.” The GBeam technology licensed to Basalt has been used for two new bridges in Hampden and others across the country.
But a Maine Department of Transportation team recommended switching to conventional steel girders, and Commissioner Dale Doughty concurred.
“Moving forward with steel girders gives us a practical path toward completing these bridges while we continue the careful engineering work needed to determine what happened,” Doughty said in a Thursday statement. “We will keep the public informed as that work progresses.”
The department stressed Thursday that its decision to switch to conventional steel girders isn’t a finding of fault or assigning responsibility for the collapse, but rather the “most expeditious” option to keep construction moving forward.
Those girders already installed will be replaced, Maine Department of Transportation spokesperson Andrew Gobeil confirmed.
Inspectors found no collateral damage to the temporary bridge from the collapse. That temporary bridge will be closed from 8 p.m. to 5 a.m. from Sept. 27 to Oct. 2 to prepare the structure for winter.
The Maine Department of Transportation is working with the Federal Highway Administration to piece together what happened to the $28 million bridge. That investigation is ongoing, and the Maine Department of Transportation said Thursday that it will take “significant time” and “complex engineering analysis” to get answers.
It’s unclear how the collapse will affect the bridge’s price tag and the timeline for completing construction.
Correction: An earlier version of this report incorrectly stated the girders were designed by the University of Maine. They were made with technology developed by UMaine and licensed to Basalt International.