Getting stuck in heavy traffic is a nightmare for many drivers, and the exhaust emissions aren’t good for the air.
Now, a new study from the University of Toronto at Scarborough suggests road traffic is also contributing to water pollution.
The study, published in the journal Environmental Research Letters, found that chemicals used in vehicle fluids, tires and paints were higher in waterways near heavy traffic.
“Traffic is a major source of a surprisingly wide range of organic contaminants on urban surfaces, and subsequently on nearby waterways,” the study says.
Water samples were collected during three rainfall events between 2014 and 2018 in the Mimico Creek (which runs through Brampton, Mississauga and Toronto) and Little Rouge Creek (which runs through Whitchurch-Stouffville, Markham and Scarborough) watersheds.
The study found that the level of contaminants was higher in the densely populated area of Mimico Creek which is surrounded by more traffic compared to Little Rouge Creek, which “drains a largely rural landscape”.
These contaminants travel from road surfaces to nearby waterways when it rains or when attached to road dust, according to the study.
Researchers say this stormwater runoff contributes to the degradation of waterways draining urban land, known as “urban stream syndrome.”
They say that while switching to electric vehicles will reduce roadside emissions, their study shows that a large number of contaminants entering urban waterways come from sources other than vehicle exhaust such as lubricants, de-icing fluids, tires and automotive paint. They suggest mitigation measures such as regular street sweeping to remove road dust, development of wear-resistant tires, and prompt repair of leaky vehicles as a few ways to improve the quality of the road. urban water.