The Maine Department of Transportation had to deploy a work crew in the middle of a snowstorm Tuesday to repair a growing hole in the Interstate 295 bridge over Forest Avenue in Portland. The job took about five hours to complete.

Traffic, already heavy because of the snow and the upcoming holiday, was slowed considerably beginning in the early afternoon when Maine DOT closed one southbound lane of I-295 near the repair site.

Ted Talbot, a spokesman for Maine DOT, said crews finished repairing the highway around 6 p.m. Traffic was flowing freely again by around 6:30 p.m.

Dale Doughty, the department’s director of maintenance and operations, explained that the bridge itself was structurally sound but that the bridge joint – a piece that connects the bridge to the highway – had deteriorated.

Doughty compared the joint to a metal strip in a home that separates two types of flooring.

“When that joint loosens from the concrete, if it gets worse, it will break the concrete and pieces will come out,” he said.

The issue was discovered a few days ago and officials planned to repair it next week. But the joint continued to deteriorate rapidly and created a safety hazard that necessitated immediate repair. Large trucks, including snow plows, likely played a role, Talbot said.

Doughty also said that Tuesday’s work is a temporary fix. A Maine DOT crew will have to return, likely in the next three to six months, to do a more permanent repair.

“This is not uncommon, especially on the interstate,” he said. “The areas where a bridge and the highway connect really take a beating.”

Bill Doukas, a bridge engineer with Maine DOT, said the crew had to dig around the deteriorated piece, reassemble a new joint and then weld it to the existing structure. He said Tuesday’s weather did slow things down, but the crew was able to keep the Forest Avenue exit open after initially planning to close it.

Staff Writer Dennis Hoey contributed to this report.