Construction continues Wednesday on Longley Bridge in Auburn as waterlines are replaced. Andree Kehn/Sun Journal

LEWISTON — The installation of a new water line into Lewiston that has snarled traffic on Longley Bridge this summer will be complete next week.

According to city staff, construction will be finished in time for the Lewiston-Auburn Balloon Festival, which kicks off Friday, Aug. 16.

While the project has caused traffic delays due to lane closures on the bridge this summer, Lewiston Public Works Director Kevin Gagne said the work has gone “very well” given the complicated nature of the project. The second water main for Lewiston has been sought for years, and was recommended when the original main was installed more than a century ago.

Beginning in March, crews installed pipeline from Lewiston’s Main Street pump station, down Main Street, under the Longley Bridge into Auburn, and along Court Street and Turner Street to the intersection of Great Falls Plaza.

While much of the work was done during nighttime hours, traffic going into Auburn from Lewiston was limited to a single lane for long stretches.

Gagne said all the piping, bridge work and trench work is complete. The waterline has passed required tests, and remaining work includes restoring pavement and sidewalks. That will include brick sidewalks on the Auburn side. A little bit of night paving also remains, he said, but following its completion, traffic patterns will be restored.

“We’ve tried to avoid it,” he said, of the overall traffic congestion. But he said the project is a 150-year infrastructure upgrade.

Officials have said because there is only one main that carries all the city’s drinking water from the lake to the Main Street pump station, “the city has always been at risk of losing its water supply if its only transmission main was ever disrupted for a long period of time.”

The current line brings water from the Lake Auburn Water Treatment Plant through Auburn and under the Androscoggin River into Lewiston. Gagne said much of the piping coming from Lake Auburn is from 1890.

The Lewiston City Council approved $9.75 million for the project in 2021 using American Rescue Plan Act funding.

Gagne lauded the city’s engineering consultant, Tighe & Bond, and construction contractor Gendron & Gendron for the smooth operation.

He said Gendron ran into some old foundations and some ledge, but that “overall for what the work was, we’re really pleased.”

“This is 150-year system changes that we’ve accomplished and I think the project went very well,” he said.

A final walkthrough and inspection will take place sometime in the following weeks.

“I’m looking forward to getting back to normal traffic patterns, definitely,” he said.