A salty brine that will be coating Edmonton's major roads for the first time this winter will cause rust damage to vehicles across the city, says a corrosion control expert.
"It's going to be out on the roads in a liquid form so it will be spread nice and evenly, hopefully waiting to catch snow and ice and melt it from the underside up," said Freeman Young, president of Krown Rust Control, an Ontario-based company that provides rust protection for vehicles.
"But the challenge with it is, it will be also be waiting to come up under your car or your truck.
"The effects of these liquid materials on vehicles is fairly dramatic."
Rust never sleeps
As part of the city's new road maintenance plan, residential streets and major roads will be sprayed with a calcium chloride solution instead of being spread with sand.
The new road-maintenance strategy was discussed July 6 at Edmonton's community and public services committee.
Doug Jones, the deputy city manager of operations, told councillors that the salt-based solution will be cheaper and more effective in keeping roads clear through the harsh winter months.
Calcium chloride melts faster than other de-icing products and — unlike sand — it can be applied before bad weather hits, preventing ice before it forms.
A thin layer sprayed on roads will keep snow from sticking, and keep the city's transportation department under budget, the committee heard.
But the same chemical properties that make it so effective on roads can prove devastating to a vehicle's sheet metal and finishes, Young said in an interview Wednesday with CBC Radio's Edmonton AM.
Like any road salt, calcium chloride will cause corrosion.
'It's a huge disadvantage'
In Ontario, treating roads with salt brines has been commonplace for years. Young said their introduction has proved expensive for the commercial trucking industry and for regular drivers.
The damage isn't just cosmetic, either.
"It's destroying wiring harnesses and it's causing huge problems with the electronics of the equipment, plus it's actually corroding underside areas that are very critical," Young said.
"There are advantages, but the disadvantages when you look at the damage to bridges or any fixtures that are actually attached to roads, and to actual cars and trucks themselves, it's a huge disadvantage."
The worst of the damage usually happens in the spring, as temperatures rise and a salt-built up on a vehicle is exposed to excessive moisture.
Jones said an anti-corrosion solution will be added to the calcium chloride used in Edmonton.
"The particular product that we're using would have a corrosion inhibitor put inside it so it would reduce the corrosion characteristics that would normally be there," he said.
"It's not just vehicles, but also bridge decks and reinforced steel within concrete. We're very aware that we don't want to apply a product that would be detrimental to all those products."
Despite those assurances, Young remains skeptical. Using liquid de-icers instead of solid treatments like rock salt can be particularly damaging, he said.
"The liquid products tend to stick around longer," he said. "I've been told the city doesn't intend to put any kind of tackifier or sticky material in it.
"If that is the case it would wash off extremely quickly. Something has to keep it on the road and if it keeps it on the road, it keeps it on the underside of the vehicle, too."
Owners of cars and trucks looking to prevent damage should wash their vehicles regularly and keep them out of heated garages whenever possible, Young recommends.
Temperature fluctuations accelerate corrosion. And once the rust starts, it works quickly.
"The average person will start to find $400, $500, $600 a year in corrosion-related problems as time goes on," said Young.
"Within two to three years, you're going to start seeing the deterioration."