Quebec City is spreading too much salt in its streets, which is causing chloride concentrations in the water to explode, reveals the auditor general in a report released Wednesday.
“The meltwater has chloride concentrations higher than the norm in most snow deposits,” notes Daniel Rancourt in his annual report.
Part of the reason is that salt-spreading machines don’t control the amount of salt they put on the streets, he says.
Normally, machines must be calibrated “at least twice per winter” if we want to reduce the use of road salts. But in the best case, they are only once. And last winter, more than 40% of the devices had not been adjusted during the first trip.
In addition, the auditor points out, the total quantity of sodium chloride is underestimated because the practices of private entrepreneurs (approximately 45% of activities) are not known.
Overflowing snow deposits
The auditor also reveals that the snow deposits are overflowing to the point of contravening the requirements of the Quebec Ministry of the Environment. Thus, two of the eight depots are used at 138% and 112% of their capacities.
In Quebec, snow depots receive the equivalent of three Videotron Centers filled to the ceiling over the course of a winter, or more than 7 million cubic meters.
The volume limits imposed by the ministry aim to ensure that infrastructures can capture as many contaminants as possible before releasing water into the environment.
However, not only are the depots overflowing, but the situation could get worse, notes the auditor, since the quantity of snow transported to the depots has been increasing for two years.
“When developing a new neighborhood, we do not evaluate the resulting increase in the quantity of snow to be transported,” observes Mr. Rancourt.
The report also mentions that the City does not have the storage capacity necessary to cope with exceptional winters like 2007-2008 and 2018-2019 during which more than 400 cm of snow fell.
The auditor is also concerned about the concentrations of suspended matter in the surface waters leaving the depots, which do not meet environmental requirements.
Finally, he criticizes the storage methods for road salts which do not meet standards either.
More details will follow.