AUGUSTA — A construction crew that is replacing a sewer line near the intersection of Chapel Street and Lambard Court accidentally damaged a pipe carrying water Thursday afternoon, affecting water service in that part of the city until the evening.

The water main break happened around 2:30 p.m. Thursday, when the tooth of an excavator that was digging in that area broke the 2-inch PVC pipe, said Andy Begin, assistant general manager of the Greater Augusta Utility District.

As workers responded to the break, they realized the repair would be more complicated because an old, nearby isolation valve had failed.

The break was repaired by 10:30 p.m., according to Begin. Overnight, the utility used a fire hydrant to flush water out of the system. That’s standard practice, Begin said, because rust that has developed in old pipes can form sediment that gets into the water when its flow is interrupted.

Water pressure might have been affected as workers fixed those problems on Thursday, and Begin said that any affected customers received a notice about the problems.

A total of 20 customers were in the area affected by the water main break. Four customers who live on Lambard Court definitely had their water service interrupted, Begin said, while another 16 might have had reduced water pressure or other interruptions.

Of the roughly 100 miles of water main that the Greater Augusta Utility District operates, it tries to replace about a mile of those pipes each year, Begin said.

The contracting company replacing the sewer main in the area of Chapel Street and Lambard Court is C.H. Stevenson.

Charles Eichacker — 621-5642

ceichacker@centralmaine.com

Twitter: @ceichacker