City blames days of extreme heat for fifth water main bust
The city’s utility department believes shifting soil busted a water main Saturday night.
A four-inch cast-iron pipe on Allen Street suffered a small puncture, Columbia Water & Light spokeswoman Connie Kacprowicz told ABC 17 News Monday. The city’s high clay content in its soil makes it susceptible to shifting in periods of extreme weather, such as the current stretch of nearly three-weeks with temperatures above 90 degrees with little rain. Kacprowicz said in that time, they’ve dealt with several main breaks.
“Most of them have been small, not affecting many customers,” Kacprowicz said. “This particular break was probably due to the weather.”
The pipe burst around 8 p.m. Saturday, but did not drop pressure enough to issue a precautionary boil advisory. For Allen Street, crews wrapped a metal clamp around the broken pipe. Kacprowicz said the city uses 20 psi as a benchmark – if water pressure dips below it during a main break, they fear potential contamination of the water system there. An advisory is different than a boil order, where a “known contaminant” gets into the system. The city issued one last week in regards to a main break downtown on Thursday night. Water & Light attributed it not only to the weather and soil combination, but to a surge in water pressure and the age of the cast-iron pipes there.
Columbia stopped using cast iron sometime in the 1980s, Kacprowicz said, beginning its primary use of PVC. The shifting soil can not only grate on the pipes underground, but can also push rocks through other buried utilities like electric lines.
“Utilities are generally safer under the ground, but that still doesn’t mean that they’re not impacted by Mother Nature,” Kacprowicz said.
In 2015, Columbia Water & Light issued 44 precautionary boil advisories in regards to water main breaks. The city also tracks the number of times a pipe is damaged to help dictate its capital improvement plan every five years. Water & Light completed work on the Texas Avenue system, for example, due to the number of times the main broke, and to better serve the growing population there, according to Kacprowicz.
