A new report by the Fraser Institute, an independent, non-partisan Canadian public policy think tank, offers optimism over the country’s freshwater quality and improvements to municipal wastewater treatment, while reminding that some work still lies ahead.
Evaluating the State of Fresh Water in Canada reports that more than four out of five, or 82%, of Canada’s freshwater monitoring sites indicated fair to excellent quality between 2014 and 2016, and only 2% of sites indicated poor water quality.
“Canadians are rightly sensitive about the country’s water supply, and the good news is that, overall, the quantity and quality of Canada’s freshwater is quite good,” announced Ross McKitrick, professor of economics at the University of Guelph, Fraser Institute senior fellow and co-author of the report, in a statement.
The report’s examination of individual monitoring stations over time indicates that, from 2002 to 2016, water quality remained stable in about 81% of locations across the country, improved in 10% of locations, and deteriorated in only 9%.
Analysis of fish tissues to discover toxic substances and their concentrations in different drainage areas suggests that, between 2013 and 2015, concentrations of polybrominated diphenyl ethers (PBDEs) in the majority of the samples across Canada were in compliance with federal guidelines. This was also the case with samples from nine drainage regions, including Pacific Coastal, Great Lakes, and St. Lawrence, taken between 2001 and 2016 in relation to guidelines for perfluorooctane sulfonate (PFOS) concentrations.
“The assessment of metals and toxic substances, including mercury and PBDEs, in the Great Lakes reveals that the concentrations have generally decreased over the past four decades,” states the report. “Another example of improving water quality is the sharp declining trend in contamination of freshwater fish in the St. Lawrence River since 1970s.”
Wastewater treatment improvements
The Fraser Institute report also suggests that improvements were observed in areas such as municipal wastewater treatment, households’ usage of chemical fertilizers and pesticides, regulatory compliance of mining operations, and releases of metals such as lead, cadmium, and mercury into waters from pulp and paper plants and wastewater treatment plants.
The report found that, while Canadian municipalities have been upgrading their wastewater treatment systems for decades (see graph), from 1983 to 2009 the percentage of Canadians on municipal systems with secondary treatment or better jumped from 40% to 69%.
Additionally, in 2009, just 13% of Canadian households relied on septic systems or haulage (down from 28% in 1983), and only 3% lacked any system of wastewater treatment (down from 20% in 1983).
Work to do
Despite improvements in the state of Canada’s water quality, the report notes concerns that require action. Though concentrations of PBDEs have generally decreased, some indicators suggest that levels of PBDEs are still above the prescribed guidelines in the Great Lakes, Pacific Coastal, and St. Lawrence River regions. Nutrient levels in Lake Winnipeg’s south basin were excessive in 2016, especially near the inflow from the Red River.
Additionally, the report found that excessive concentrations of nutrients in the Great Lakes—specifically, in Lake Erie and some near shores of Lakes Ontario and Huron—have caused a resurgence of harmful algal blooms in these areas. Despite significant reductions in mercury levels in Lake Erie in Ontario since the 1970s, analysis of recent mercury concentrations on fish contamination in this lake suggests that levels have stopped decreasing or started increasing. Despite reductions in nutrient levels in recent years, excessive nutrient concentrations appear to still be a problem in the St. Lawrence River and its major tributaries.
“Stresses on water quality do exist, but the overall assessment of Canada’s freshwater is quite positive,” said Elmira Aliakbari, the Fraser Institute’s associate director of natural resource studies and study co-author, in a statement.