LEWISTON – City water service was back to normal Saturday night after crews found a massive leak that cost the city about 7.5 million gallons of water.

“But now it’s over,” said Dave Jones, city public services director. “Now we know where the leak is, and it’s just a matter of fixing it. Before, all we could do was look. We can deal with this.”

City Street Superintendent Denis Caron found the leak in a 24-inch cast iron pipe under Island Avenue, the dead-end road just north of Espos Trattoria. The leak was pouring city water into the Androscoggin River, beneath the river’s ice.

Jones said it was too soon to say what caused the leak.

“We’ll go in and look before we know what has to be repaired,” he said.

They had water service detoured around it by 3 p.m. Permanent repairs could begin Monday or Tuesday.

City water crews noticed that the water level at the city’s Webber Avenue reservoir was down at about 3 a.m. Friday. Pumps used to refill the reservoir were working, but didn’t change the water levels.

They estimated water was leaking from the system at a rate of 3,500 gallons a minute and began combing the city.

City crews had nearly exhausted their ground search options Saturday when Caron came upon the leak. City Finance Director Dick Metivier said he was on the runway at the Auburn Lewiston Municipal airport, poised for takeoff in a chartered plane. He was going to fly over the city looking for puddles.

“That was the only thing we could think of, since we’d pretty much walked everywhere we could,” Metivier said.

Caron said he stumbled on the leak by sheer luck.

“We figured that the leak had to be in a body of water because there were no big puddles anywhere,” he said. He noticed that the ice between the Androscoggin River and Island Avenue was melted, despite continued freezing weekend temperatures.

Crews brought in a ground sensor and used it to locate the exact spot. They had water service detoured around it by 3 p.m. Permanent repairs could begin Monday or Tuesday.

Water service was cut to three buildings – the Florida Power and Light office building on Main Street, the FPL Monty Hydro Facility at the end of Island Avenue and the Espos Trattoria building. Jones said the water would remain off at the two FPL buildings until repairs were finished. Crews ran a temporary water line to Espos to keep them open.

The city had asked residents to conserve water while they looked for the leak. Jones said citywide water service was back to normal by 9 p.m., and rationing was no longer necessary.

Levels at the Webber Avenue reservoir should be back to normal by Sunday morning, Jones said.