Add sewer lines to the list of things freezing following the third coldest February on record and a winter of sub-zero temperatures. 

Decorah Water Superintendent Todd Ihde reported during Monday night’s Decorah City Council meeting that residents need to remain diligent in checking their water temperatures to avoid freezing water service lines despite warmer weather.

“And we’re starting to have issues with sewer lines freezing at residences. People need to pay attention to what’s going on,” Ihde told the Council.

While there are steps to take to avoid freezing water lines, there’s really no preventative measure that can be taken to avoid frozen sewer lines, according to Rick Bohr, assistant water superintendent.

“If your pipe is laying flat as opposed to tipped, and water sits in one spot and it’s fully encased in frost, it’s going to freeze,” Bohr said.

 However, freezing sewer lines might occur more often when homeowners are away.

“If someone is using a lot of water, doing dishes, laundry, there’s more flow to help push things along,” Bohr said.

He said he’s not aware of any sewer pipes bursting, but it’s not something a homeowner would necessarily see.

“If it’s PVC or clay or cast iron, it could crack. It’s just frozen right now,” he said.

Frozen sewer lines have occurred at about six locations in the city so far, Bohr said. Half the locations have chronic issues with freezing, the others are unique to this winter, he said.

When the line is frozen, whatever is flushed will end up in the floor drain, Bohr said. It’s not the same as when a city main is plugged and sewage backs up, he said.

“You’re not going to get rid of what you want to get rid of,” he explained.

Residents experiencing problems should contact their plumber.

“They’ve had luck getting them open with steaming. Some plumbers have mini jetters,” Bohr said referring to a machine that heats water to 60 degrees and “jets” it into the line to open it.

The steam machine is the same being used to open frozen water lines, but different tubes are used for each process, he said.

Remain vigilant

While temperatures are warming up, Ihde said the ground temperatures remain “very cold” and he is asking home and business owners to “please monitor and pay attention to water temps.”

To measure the water temperature accurately, the water department advises running only the cold water faucet for about five minutes, then filling a glass and taking the temperature using any thermometer that will measure to at least 30 degrees.

If the water temperature is below 40 degrees, homeowners should run a very thin stream of water from their faucet. This may need to be done for an extended period of time or as recommended by a plumber. Basements and crawl spaces must also be heated to prevent water line freezing.

Because of the high number of frozen service lines and water mains, residents should call their local plumber to assist with service line issues. Call the Water Department at 563-382-5171 or City Hall at 563-382-3651 to determine if there is a broken or frozen main or when water problems are experienced.