Calcium chloride helping reduce collisions, says report recommending continued use
A new report says the city’s de-icing strategy – which includes the use of a controversial agent – has made Edmonton’s roads safer.
The Snow and Ice Control pilot program saw the number of crashes in intersections clear of snow and ice drop by 12.5 per cent in 2017-2019 compared to the five years prior, according to a report presented at the city’s Community and Public Services Committee Wednesday.
The report also says all collision types where reduced when bare roads were achieved with calcium chloride, a de-icing compound that some Edmonton residents have expressed concern over.
“This reduction in collusions has significant societal safety benefits,” the report says.
The city has been criticized for using calcium chloride, with some saying it’s too corrosive and can damage surrounding environments.
'Better data' needed
“The discussions had and the meetings with administration are not accurately reflected or represented in the reports you’ve been provided today,” said Derrick Hiltz of the Canadian Home Builders Association.
Hiltz and others lined up to speak at the meeting accusing the city of cherry-picking facts when it comes to the negative side of calcium chloride.
“We need to get better data, so on the corrosion side, there was some really bad work done there from what I could read,” said chemical engineer Arthur Potts. “Let’s make sure that if we’re doing field testing, we do it so it gets us meaningful results.”
An expert who studied the effects of calcium chloride in Denver, Colorado said eventually, he expected roadside foliage will be impacted.
“It’s totally gradual and it may not be evident at first, but the most important thing is that at a certain point, we may lose trees,” said Jon Oulette of the Urban Development Institute.
City has 'trust issue'
In the report, city staff said the use of salt and brine had little-to-no negative impact on concrete and asphalt.
The study did find that chloride-based solutions including calcium chloride were “more corrosive than concentrated brines,” but the addition of an inhibitor reduced corrosivity.
It also noted that exposed metal should be protected by paint, coatings and washing to limit corrosion.
The report said soil near roads treated with salt and brine was found to have relatively high salinity at all 12 testing sites, but salinity was lower for sites treated with additional anti-icing brine versus sites treated with a sand and salt mixture.
It went on to recommend the continued use of blading, sanding, de-icing and anti-icing agents including calcium chloride “even with the potential impacts to infrastructure.”
Despite the recommendation, Ward 5 Coun. Sarah Hamilton said there’s clearly a trust issue with the public on the matter.
“We could remove the calcium chloride from the toolbox, I don’t know if it addresses the actual full nature of the concerns we’ve heard,” said Hamilton.
But city staff say they want to keep the de-icing agent handy for road maintenance this winter.
“If you decrease the size of the toolbox, you’re going to have an impact on achieving some of those goals like bare pavement,” said deputy city manager Gord Cebryk.
As for potential impacts to private property, a lawsuit has already been launched against the city by a man who says calcium chloride damaged his garage pads.
The plaintiff is seeking $50,000 in damages, but the city is standing by lab results showing the chemical doesn’t cause serious damage.
Council will make a final decision on the recommendations at a Sept. 24 council meeting.
With files from CTV Edmonton's Jeremy Thompson