Chalk it up to bad luck.

A water main break that led Lewiston officials to ask residents to conserve water this past weekend was caused by construction crews working on a secondary main from Lake Auburn.

Ironically, the purpose of the backup water main, which cost roughly $10 million, is to avoid situations like these.

According to Public Works Director Kevin Gagne, the contractor working on the secondary line, which is nearing completion, accidentally hit the primary line Friday morning.

As soon as the break occurred, Lewiston’s pumps were shut down and the city’s reservoir system automatically began feeding the system. Gagne said that is normally good for 24 hours, but as the city was waiting for water samples to be tested to make sure no contaminants were present, officials decided to issue the advisory out of caution.

The notice, issued around 9:30 a.m. Saturday, asked residents to conserve water until 3 p.m. as a precautionary measure “to ensure an adequate water supply remains available.” Residents were asked to avoid watering lawns, washing cars or filling pools.

“This instance was a unique situation that’s hard to plan for,” Gagne said Monday, adding that crews are close to tying in the secondary main to the system next to Lake Auburn.

The secondary water main line, which has been under construction for more than a year, was funded by $9.75 million in American Rescue Plan Act funds in 2021. At the time, officials said the secondary main had been at the top of an infrastructure wish list for years, having been suggested more than a century ago when the original main was installed.

Because there is only one main that carries all the city’s drinking water from the lake to the Main Street pump station, officials have said 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.

Gagne said the main was repaired within a couple hours of the break Friday, but concern was raised later Friday about possible contaminants, at which time the tests were conducted. The tests came back normal around 3 p.m. Saturday and the system was back to running as normal.

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, which makes it more difficult for construction crews to trace the exact location.

The construction of the line, which disrupted traffic on Longley Bridge last summer, will likely be complete within the next few weeks and will be online within the next two months, Gagne said.

The final connections to the Lake Auburn treatment facility will occur soon, but the new main will require final inspections before being made active.

Starting last spring, 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. This year, Phase 2 of the project continued the installation from North River Road to Stetson Road in Auburn.