Road Salt vs. Beet Brine: De-Icing in Canadian Cities


I first heard of the technique of using beet brine to de-ice roads through a CBC article back in November, 2018. I then heard it again on Monocle's podcast – Monocle 24: The Urbanist, where the host of the program highlighted the use of beet brine on Calgary roads. This led me to investigate the use of both salt and beet brine as ways to combat snow and ice buildup on Canadian roads.

The traditional method in Canadian villages, towns and cities is to spread a mixture of salt and gravel onto driveways, sidewalks and roads; it is the snow and ice removal standard. Regarding beet brine, Calgary and Toronto have used it occasionally, though never on a mass scale. Transportation and infrastructure expert with the University of Saskatchewan, Carl Kuhnke writes “why then do Canadian municipalities, cities and provinces turn winter after winter to sodium choloride? Because it’s cheap. It’s really a matter of cost benefit. Anything above the 45th parallel will use some variation of sodium chloride to provide more friction on the roads.”[1] I would like to take this idea of cost benefit and apply it to sodium chloride compared to beet brine.

While sodium chloride may be cheaper than alternatives, the side-effects are both costly and can shift the cost towards the individual; for example, the damage sodium chloride can do to the underbelly of vehicles, our clothing and our pets’ paws. Simply consider the resources and finances it involves to mitigate those damages; to prevent rust from forming on cars and trucks, to replace one’s clothing or to buy boots for our dogs. Additionally, “road salt helps speed up the corrosion of rebar inside concrete. Salt corrosion has been cited as a contributing factor in the degradation of bridges in Quebec — like Montreal’s Champlain Bridge — and is one reason for the crumbling state of Toronto’s Gardiner expressway.”[2] If sodium chloride is doing all this damage, why are we still using it?

This moves the topic towards an alternative; specifically, beet brine. “What most Canadian cities have tried is mixing together sugar beet molasses, a waste by-product of beet sugar refining, together with existing salt solutions in order to cut down on the concentration of salt needed to produce the same ice-melting effects.”[3] This approach can decrease the amount of salt used or eliminate it at all when the mixture is 100% beet brine. Additionally, “the stickiness of the molasses additionally helps bond the salt to the surface of the road, where it can maximize its effects.”[4] Beet brine also has a lower freezing point than a salt, effective at temperatures above -30 C, whereas salt is only effective until about -25C. The solution doesn’t come without its downsides, as “National Geographic reported in 2014… that it can sometimes leak into streams, where the sugar attracts bacteria that suck up all of the oxygen in the water on which animals rely.”[5] Ultimately, more research is needed to investigate the negative effects of the mixture, as it hasn’t been used on a mass scale before. It’s safe to say though, that beet brine does not have the corrosive and damaging affect that sodium chloride has, making it a better option in this regard. Ultimately though, the barrier is cost; cost in the local government budget.

In terms of its actual use, former Toronto Star writer Liam Casey writes, “the city won’t spray every road with the stuff because it’s about four times more expensive than salt. But they’ll hit strategic parts of the city, such as hills and bridges, where ice is most likely to cause problems.” Again, while it may be more expensive, the negative externalities of sodium chloride need to be looked at closely to highlight their true cost to society. In conclusion, both mixtures have their pros and cons, though it is vital to take into consideration the costs of either method and to determine what portion of that cost is transferred to the individual. Governments may choose to use beet brine, while initially more expensive on their budget, the negative external costs are not passed onto their citizens, whereas that is the opposite in sodium chloride use. Of course more research has to be done on beet brine and its effects, though through this cost benefit lens, it may turn out to be the better option in terms of snow and ice removal.

Thank you to Jing Min for her insight and previous work on the topic.