Minnesotans are welcoming the relative warm-up to above-zero temperatures after last week's historic deep freeze, but the thaw also comes with complications, including bursting water main pipes across the metro.

While it seems contrary to reason that more pipes would break when it's 30 above than when it was 20 below, the extreme fluctuations in temperature are to blame. Experts say lower-than-usual temperatures drove frost deeper, causing water mains to shift and putting more pressure on aging 40- to 50-year-old lines. Also, the subzero weather caused pipes to freeze and crack, allowing water to shoot out when they thawed.

"It's just kind of inevitable," said Josh Werner of Valley-Rich Co., the company that repaired a break Saturday in Wayzata.

That break detoured hundreds of cars for nearly seven hours on a popular road along Lake Minnetonka, where crews worked to fix a cracked cast iron pipe that was connected to a water main on County Road 101, also known as Bushaway Road.

It was the seventh water main break Hennepin County senior engineering technician Mike Olmstead has responded to in just over a week.

"It's been a real busy last 10 days," he said.

City and county crews scrambled last week to fix pipe breaks in Mound, Hopkins, Richfield and Edina, Olmstead said. In Duluth, a burst pipe flooded several stores Wednesday, according to the Duluth News Tribune. And in St. Paul, residents in River Park Lofts were still drying out Saturday after a pipe broke Tuesday on the fourth floor, sending water raining down into 14 units.

Restoration Professionals, which dealt with the flooding in the River Park Lofts, has been called to 75 homes and businesses that have dealt with frozen pipes since Jan. 1.

"Over the last week, it's just been crazy," manager Richard Larson said. "Once it starts warming up, it gets busy. We've had crews basically working 24 hours a day."

In Wayzata, Olmstead said Bushaway Road has water main breaks one or two times a year because the aging pipes are so susceptible to swings in temperatures. But that will change later this year.

The narrow road that winds along the lake from Wayzata to Minnetonka is slated to undergo a major reconstruction project starting in the spring that will replace the water main pipes along with other improvements on a stretch that more than 11,000 cars travel each day. The latest break left 12 homes without water for a few hours Saturday but didn't damage any properties.

"Everybody got lucky on this one," Olmstead said.

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