6 feet deep

MARQUETTE – The prolonged frigid temperatures are taking their toll on Marquette residential water service lines.

Considering the frost depth is at more than 6 feet, it shouldn’t be surprising crews already have responded to 426 freeze-ups as of Thursday afternoon, according to city staff.

Through the winter seasons of 2009-10 through 2012-13, city stats show no freeze-ups. During the winter of 2008-09, there were 25 freeze-ups reported.

Also, at least 1,400 let-run orders were placed as of Thursday afternoon. Residents of the affected homes were asked to let their water run to prevent pipes from freezing or refreezing.

During the 1993-94 winter, the city thawed at least 510 residential water service lines, although it was estimated the number actually neared 800 since crews often would meet neighbors with frozen lines, and those cases weren’t always recorded.

Service lines typically are buried 6 feet below ground, so freeze-ups usually aren’t a problem unless there’s a brutal winter.

This has been a brutal winter. The National Weather Service in Negaunee Township, for example, reported there were 20 days at or below zero degrees in February alone. The average temperature from Dec. 1, 2013 to Feb. 28 was 7.5 degrees, breaking the old record of 8.5 degrees set in 1963.

The city has a prep crew that responds to homes with frozen services lines, using two methods to thaw the lines.

One method uses a trailer-mounted welder, which a crew uses to direct an electrical current through the frozen pipe. The heat that’s generated melts the ice, and once the ice breaks loose, the customer is advised to run the water until further notice.

Another method uses a Pulse Jet De-icer, which is composed of a pump, a heating tank and a flexible hose. The hose is fed into the frozen pipe, and heated water circulates through the hose, melting the ice.

With the current frost depth, some crews have been working 12-hour shifts seven days a week, with employees also borrowed from the Wastewater Treatment Facility and Water Filtration Plant.

“It’s always good to give credit to them,” said Curt Goodman, city director of public works and utilities.

Goodman said he expects the situation to continue another month.

“The freeze-ups are really unpredictable, how much you get each day,” Goodman said.

Anyone who suspects their utilities are freezing should contact the Department of Public Works at 228-0444 from 7 a.m. to 5 p.m. or 228-0488 after business hours or on weekends.

It is recommended people keep a few jugs of water suitable for drinking, plus a bucket of water for toiletry use, in the event of a water freeze-up.

Updates and more information, as well as public service announcements, can be obtained at the city website at www.mqtcty.org.

Christie Bleck can be reached at 906-228-2500, ext. 250.