Southern Ontario waterways are showing dangerously increasing road salt levels in WWF-Canada’s Great Lakes Chloride Summer Hot Spot Map.
Although road salt – sodium chloride, calcium chloride and magnesium chloride – keeps public areas safe during icy winters, it is a critical threat to the health of Ontario’s freshwater and wildlife.
More than 7 million tonnes of road salt are used in Canada each winter by public road agencies alone. Road salt use by the private sector and small towns is not currently tracked or controlled in Ontario.
Road salt’s chloride component is toxic to species and ecosystems year-round. The runoff from winter applications is affecting the creek and river habitats for species like fish, frogs and mussels – where these chloride levels endanger their survival during spawning season in the spring and summer months.
The Summer Hot Spot maps reveal many urban and rural waterways in southern Ontario – including the Greater Toronto Area, Stratford, Barrie and Kitchener-Waterloo – are showing record high chloride levels. Some are even as salty as the ocean.
WWF-Canada’s maps will help inform policy recommendations to the Ontario government. These include establishing a Provincial Water Quality Objective (PWQO) to address species-at-risk susceptible to chloride levels; regulating road salt application, including mandated training and certification; and developing liability benefits for public and private holders that track and record evidence for maintaining public safety and environmental health.
The Summer Hot Spot maps is based on data collected during the summer months (May-October) and allows users to compare chloride levels from 2007-2011 and 2012-2016. Researchers can also look up specific addresses to learn about threat levels in nearby bodies of water using the public map: https://bit.ly/2Rs0D5Y
Elizabeth Hendriks, vice-president of freshwater says:
“While healthy levels for aquatic life should be less than 120 mg/L, our maps show some areas in southern Ontario currently have levels greater than 1000 mg/L year-round. Ontario is over salting its parking lots, sidewalks, and roadways. A small pill bottle or salt shaker is all that’s needed to melt the equivalent of a city sidewalk slab.”
About World Wildlife Fund Canada
WWF-Canada creates solutions to the environmental challenges that matter most for Canadians. We work in places that are unique and ecologically important, so that nature, wildlife and people thrive together. Because we are all wildlife. For more information, visit wwf.ca.