Toronto’s sewage treatment plants release more wastewater into the natural environment than any other facilities in Canada, a new report from the Commission for Environmental Cooperation (CEC) reveals. Taking Stock examines North American pollution sources, covering air and water releases data from 2006.
Industrial facilities release more than 228 million kilograms of pollutants into North American surface waters each year. Public wastewater treatment plants account for just under half (44%) of those releases.
Here’s how Canada measures up:
- Toronto’s Ashbridges Bay Treatment Plant is the #1 polluter of surface water in North America with an annual on-site surface water discharge of over 13.5 million kilograms.
- Canada accounted for half of the surface water pollution discharges in North America.
- Wastewater treatment plants accounted for 84% of Canada’s total water discharges.
- Among the top 10 polluters to surface water in North America, four are wastewater treatment plants that discharge directly into Lake Ontario.
The CEC report also reveals that the Great Lakes are taking a big hit. About 22.5 billion litres of water are withdrawn from the Lakes per day for drinking water. We drink the water, but we also contaminate it: of the top surface water polluters in Canada, eight facilities discharge right into our Great Lakes.
In addition to bacteria, which causes beach postings, sewage releases contain all kinds of chemicals, perfumes, pharmaceuticals, as well as pollutants like these:
- nitric acid and nitrate compounds
- ethylene glycol
- N,N-dimethylformamide (carcinogen)
- acrylic acid
We don’t know if Toronto’s sewage treatment plants (Ashbridges, Highland Creek, Humber) are the worst in North America, since the CEC report does not include data for U.S. sewage treatment plants. We do know that they are three of the worst in Canada. Throw in the Halton sewage treatment plant, and four of the top ten surface polluters in Canada are on Lake Ontario.