A large water main break in Waterbury involving millions of gallons of water draining out of about 10 miles of pipes led to schools being closed on Wednesday and at one point left about half the city without water.
The break occurred in the late evening hours Tuesday on Huntington Avenue and involved a broken air relief valve on a 30-inch high-pressure transmission main, according to Mayor Paul K. Pernerewski, Jr.
Crews were at the scene throughout the night and into the next day, but Pernerewski said in the morning hours that they could not begin repair work until all the leaking water had completely drained. City officials expected the water to be fully drained by the afternoon hours, as it involved about 10 miles of pipes and between 3.5 to 4 million gallons of water.
“So typically when something like this happens we would have been able to localize the problem by shutting off valves in the area,” Pernerewski said.
“Unfortunately, because of the age of those valves we’re unable to get them shut off, so we cannot stop the water flowing out of here and get in to make the repair,” he said, adding that the underground infrastructure in most places in the city is more than 100 years old.
Had the entire pipe burst, Pernerewski said, it would have drained a lot faster and allowed crews to begin repair work sooner. Because the leak involved a 2-inch relief valve, it took a lot longer to drain, he said.
City officials made the decision to close schools after it was determined that some of them would be without running water. At one point, according to city officials, about half of Waterbury was without water service.
“A good portion of the city” was expected to lose water service at some point on Wednesday, which had already begun in the early morning hours in some of the higher elevation areas, according to Pernerewski.
Pernerewski said city officials were closely monitoring the situation at Waterbury Hospital, which was able to use reserve tanks for water service.
Once crews were able to begin work in the afternoon hours, Pernerewski said, water service was expected to be back within about an hour barring any unforeseen challenges.

