When the city was hammered this week by a major snow storm, dropping 33 cm in very short order, the conditions were ripe for the sort of road rutting drivers experienced for the rest of the week.
The reason? Tony Cecutti, the city's infrastructure GM, said Friday it was the combination of heavy snow falling so quickly, and the extreme cold conditions that made salt useless.
"It's not uncommon for us to get 33 cm of snow, but it's very uncommon to have that kind of snow with it being -20 or colder,” Cecutti said. “When you get those kinds of temperatures, you can't use salt." After the mercury drops to -12, road salt loses its effectiveness, he said, forcing crews to switch to sand. "
At -20, salt has no effect at all -- it just blows off the side of the road," Cecutti said. "And it's a very expensive product -- it's 10 times more expensive than sand, so we don't want put it down if it's all just going to roll over into the curb."
When a road is plowed and sanded when the snowstorm is still ongoing, when cars drive over the road, heat from their tires melts the snow a bit, creating patterns on the road that quickly freeze. Then the next car does the same on the next layer of snow, and so on, creating the ruts.
"During the snow storm, cars are still out there driving around, and they're packing the snow down onto to the asphalt,” he said. “They're forming ice just by driving on the road.”
Temperatures usually warm up in the days after a major snowfall, but it was brutally cold all week. It warmed up a bit Friday, Cecutti said, allowing the crew to get out there and salt those areas, created a granular soup-like substance that plows can remove.
"Temperatures are a little more mild today, and the salt seems to be taking effect and the roads are certainly loosening up right now," he said. "We've been using graders with ice blades to shave it down as close as we can to the asphalt, and we put sand down, which forms a bit of the grit and gives cars a little more traction."
Rutted roads aside, Cecutti said he was pleased with how city and contractor crews performed in the first major challenge this winter.
"I was quite pleased,” he said. “In fact, Tuesday at noon it was still snowing quite heavily, but pretty much by midnight that day, we had all the roads pretty much all first-pass. By the next day, we were back in business."
Assuming we get some warmer temperatures, Cecutti said they hope to get the major roads back to bare pavement next week. He also urged drivers to remember to slow down and give themselves more time to get where they're going.
"And be patient on the roads, he said. “Give snow plows time to move around. We encourage people to stay behind the plows. Don't try to pass them, because it's a really big piece of equipment with a lot of moving parts. It's very unsafe to try and pass a plow.
"The plow will eventually take a corner or turn and you can get by them then.”
