Cold snap led to daily water main breaks, city says
by Thia James, originally posted on January 16, 2017
Crews have dealt with water main breaks daily since the cold snap last Wednesday, according to the City of Saskatoon’s director of Water and Waste Stream.
Russ Munro said the city typically experiences five such breaks over the course of a week during the winter. He said the rate of breaks in the last week isn’t atypical for this time of the year.
He said when we get a cold snap the frost penetrates deeper into the ground, particularly when there isn’t a lot of snow on the ground to insulate it. The frost shifts the ground, putting stress on pipes, which can lead to breaks.
“The frost goes in wherever it wants to go in and that’s something we can’t really fight,” he said.
The work on the water main that broke in the 300 block of Duchess Street was well under way on Monday morning. In a statement about the break, the city warned of rapidly fluctuating temperatures causing “dramatic” ground shifts which can break pipes regardless of their age.
Temperatures in Saskatoon have quickly rebounded from last week’s cold snap. For each of the first 12 days of 2017, the daily lows were below -20 C, getting as low as -35.9 C on Friday without the wind chill.
According to Environment Canada’s forecast, the temperature will rise over the course of the week, until it peaks at a high of 5 C on Friday.
The two previous years were milder years, Munro noted and Saskatoon experienced fewer water main breaks than in 2014. The city experienced 320 water main breaks in 2014.
Temperature swings could also lead to breaks related to frozen water line connections to homes and sewer line breaks if the frost were to get that deep.
Casey MacLeod, spokesperson for SaskEnergy, said temperature fluctuations can affect the soil, particularly in areas with heavy moisture and clay-like material. The ground could shift and damage gas lines.
“Any time of year you think you smell a rotten egg smell, better safe than sorry, give us a call and we’ll come check it out. We do see more leaks happening in the spring when the ground is shifting from the thaw,” she said.
The freeze-thaw could also lead to meters and external furnace vents being encased in ice. In the case of the latter, carbon monoxide could build up inside the home.
Temperature swings similar to the one Saskatoon has experienced in the last few days may happen more frequently, one researcher says.
Bill Patterson, an isotope biogeochemist at the University of Saskatchewan, said warm wet air is coming off the Pacific Ocean while warm air is also coming off the Rocky Mountains, leading to this week’s forecasted temperature increase.
“It’s not a typical situation that we have warm air streaming up from the southwest. Normally, we have cold air streaming down from the north,” he said.
Patterson said the warmer weather is also related to the decrease in summer sea ice in the Arctic. He said the disappearance of sea ice associated with the warming of the Arctic may lead to changing circulation patterns thousands of kilometres to the south.
For all of these climate patterns, which are changing at different rates, to converge and be doing the same thing at the same time is rare, Patterson added.
“It may happen more frequently if we change conditions, say ice coverage of the Arctic, for instance.”