The authors also found that levels of other urban contaminants such as metals, E. coli and coliform were all elevated well above Canadian water quality standards. A decline in ecosystem diversity in Frenchman's Bay is also noted in the report, reflected in the absence of fish in creeks, significant changes in the age structure of fish populations and a much lowered diversity of aquatic species. The report highlights the loss of wetlands by urban runoff.
The contaminated water from Frenchman's Bay flows directly into Lake Ontario and Eyles says it is typical of many urban watersheds across the Great Lakes basin. This basin is home to 36 million Canadians and Americans. The urban impact on the lakes is a major concern because these waters are used for drinking supplies. The water quality of the Great Lakes was identified as being at risk from urban development in the 2003 International Joint Commission's Great Lakes Water Quality Board report, he notes.
The $500,000 study by Eyles and Mariano is one of the most specific and detailed geological research projects on any watershed in Canada, and one of the most well financed studies of its kind, with thorough multi-year monitoring of conditions in both summer and winter. The authors hope the report will highlight the impact of urban development and infrastructure on water quality, not just in Frenchman's Bay but in all bodies of water near urban areas.
|Contact: Eleni Kanavas|
University of Toronto