Cold snap threatens water mains, city says
Waterworks director balances demand for quick repairs with worker safety
Colder temperatures may bring more water leaks to the surface, according to the city.
So far this year, according to the city waterworks director Pat Wilson, the number of water-main breaks has been only slightly higher than average.
But recently as temperatures fell, numbers have started to rise. According to Wilson, there were reports of seven new breaks on Tuesday alone.
“We’re certainly seeing an increase in the number of leaks. But until we dig, we don’t necessarily know if it’s a water main or if it’s a service connection,” Wilson said.
While water-main breaks typically affect a whole block, a service connection typically affects only one household. This year, there were about 20 recorded water-main breaks in January, compared to 27 in January 2018. As of Feb. 10, there had been five to seven breaks.
Although winter is always challenging when it comes to water mains, Wilson said continuously cold temperatures can create more breaks as the frost line continues to go deeper. Wilson said the frost line is currently between four and six feet deep, depending on the area, while water lines tend to be about seven and a half to eight feet down.
“In some places, we’re starting to get into that range where the frost is moving the ground and having an effect,” she said.
When there is a break, the water often travels underneath the frost and may surface at a distance away from the actual break, creating challenges for repairs, Wilson said.
On average, repairing a water-main break takes a few hours. However, repair time increases with the cold weather, from the increased effort to the time needed for crews to switch off to stay warm.
“It’s obviously extremely difficult work for our staff when we have main breaks. They’re working in water in the extreme cold, it starts to freeze, and we get the water coming up to the surface.” Wilson said.
Sometimes, in extreme cold, she said this means sending out a larger crew so they can take shifts keeping warm.
In addition, to get to the water lines, crews need to use a frost wheel, which Wilson describes as “an enormous saw, that just cuts through the pavement, the frost, and everything.” However, not every repair crew has a frost wheel, and the waiting time to use the equipment increases repair time.
In some cases, a grader may need to do some cleanup before repair crews can begin work on the location, to ensure safety.
“We want to make sure that we balance keeping our workers safe, and getting the water turned on as quickly as we can,” she said.