Présentations Colloques

Drinking water source protection began in Ontario in response to the Walkerton tragedy in May 2000, when seven died and thousands became ill from drinking municipal water contaminated with E. Coli and Campylobacter bacteria. The public inquiry that followed recommended a multi-barrier approach to protect drinking water from source to tap. In response, the province passed the Clean Water Act in 2006 as the first barrier. The intent of this new legislation was to protect the sources of drinking water before it enters municipal water systems. **Scientists across the province were tasked with developing Assessment Reports to characterize the quality and quantity of drinking water resources. In addition, these reports documented the human and ecological features, mapped areas vulnerable to impacts from human activities, and enumerated significant drinking water threats. The technical work included integrated mapping of surface and subsurface features, groundwater surface water modelling, contaminant transport, capture zone analysis for municipal wells, and enumeration of significant drinking water threats. **At Toronto and Region Conservation, 456 significant drinking water threats were identified with respect to municipal wells, and locally developed policies were developed to eliminate or manage these threats. The source protection policies were developed into a Source Protection Plan by scientists, engineers, and planners who worked in partnership with a local Source Protection Committee. Each of the 19 committees across the province included a mix of municipal appointees, industry representatives, and watershed residents. **The policies for the jurisdiction of Toronto and Region Conservation took effect December 31, 2015. These policies are based on science, and yet recognize the existing fabric of land development and the effects of human activities on the landscape. We have met the challenges of implementation of new policy tools by a variety of government agencies by ensuring rigorous public consultation, inter-agency meetings, and provincial oversight.**