What comes with the thaw: Pipe damage? Floods? Certainly potholes
Rising temperatures through Monday's unseasonably warm forecast of 49 degrees will undoubtedly be a physical relief to suburban residents who've suffered through this week's historic lows, but the accompanying thaw could trigger some problematic flooding and potholes.
It was still too early Thursday to predict the precise pace and degree of the thaw before temperatures return to seasonable norms Tuesday, National Weather Service meteorologist Amy Seeley said.
"It'll put a dent in the snow," she said. "It's not all going to disappear."
While some rain may be among the precipitation in the days ahead, it won't contribute to any flooding that might result from melting snow, Seeley said. However, the inch or two of new snow expected to fall between Thursday and Friday would.
Nevertheless, any potential household flooding caused by melting snow pales in comparison to the likelihood that damage already done to frozen pipes won't be noticed until the thaw, said Dirk Hoerr, president of Budget Right Handyman in Chicago, which serves Cook, Lake, DuPage and Will counties.
Ice may be concealing cracks in those pipes, lulling homeowners into believing they've survived the deep freeze unscathed, he said.
"People should be proactive and check all faucets," Hoerr said. "It'll happen pretty quick."
The Chicago office of the Federal Emergency Management Agency also shared some tips to help homeowners through the imminent thaw.
These included clearing snow piles and ice away from foundations and gutters, inspecting basement walls, sealing foundation cracks with caulk, and considering a basement sump pump or professional installation of sewer backflow valves.
Experts say flooding along the Fox River, Des Plaines River and on the Chain O' Lakes could be an issue as temperatures rise this weekend.
The lakes in the Chain are lowered each fall to accommodate water from spring thaws, said Joe Keller, executive director of the Fox Waterway Agency. But if the snowmelt and rain exceed the storage capacity of those lakes, flooding is a possibility, he said.
Predictions are hard to make now because the ground is frozen and unable to absorb water, Keller said.
"As much preparation that goes into minimizing flood occurrences, with these whipsaw-like weather events, which have seemed to become the new normal, it can be tough," Keller said.
To the east, the Des Plaines River likely will hit flood stage in the next few days, said Mike Tully, chief operations officer of the Lake County Forest Preserve District.
Current levels are low, however -- several feet below flood stage, according to the National Weather Service.
The weather service's estimates for Des Plaines River depth can be viewed online at water.weather.gov/ahps2/hydrograph.php?gage=guni2 & wfo=lot.
This week's freeze-and- thaw cycle is also likely to cause asphalt roadways to crumble and potholes to appear.
Streets already showing signs of deterioration are vulnerable to potholes, said Adam Boeche, Mundelein's director of public works and engineering.
"Once the snow and ice melt, the water begins to infiltrate into the base of the pavement. Then it freezes again, causing the base to heave and expand the roadway surface," Boeche explained. "If there are already cracks in the surface, they begin to separate more, thereby losing the integrity of the pavement and forming potholes."
Drivers and residents are encouraged to report potholes to local public works departments. People should drive slowly and cautiously when navigating streets with potholes, said Lincolnshire Public Works Director Bradford H. Woodbury.
If you hit a pothole on a state highway or tollway and damage a tire or axle, Illinois State Police Sgt. Jacqueline Cepeda said, you should stay in your car with your seat belt on while you call 911 or a roadside assistance service.
If your car isn't disabled, drive it to a shoulder or safe location before making that call.
Cepeda's advice on avoiding potholes is simple: Keep your eyes on the road.