Grant: Alliance Grants

Septic systems, also known as onsite wastewater treatment and dispersal systems, are widely used across Canada in areas not serviced by centralized wastewater treatment plants. It is estimated that up to 20% of septic systems in Canada may be failing leading to high inputs of wastewater effluent and associated contaminants into the environment. These contaminants which include nutrients, fecal pollutants (bacteria, viruses), pharmaceuticals and personal care products pose major human and ecological health risks. The overarching project goal is to work together with our Partner Organizations, Ontario Ministry of Environment Conservation and Parks (MECP) and Ontario Onsite Wastewater Association (OOWA) to improve estimates of contaminant loads from septic systems to streams and rivers. In addressing this objective, the project will provide our partner organizations and other stakeholders with new knowledge and tools needed to assess, manage and mitigate the impact of septic systems as source of contaminants to surface waters. The project will combine novel field methods and investigations with geospatial data analysis to evaluate the prevalence of septic system failures and the pathways delivering septic system wastewater effluent to streams and rivers. The relationships between physical and demographic watershed characteristics and the magnitude of septic system wastewater inputs to streams and rivers will also be assessed. The understanding gained will be applied to develop geospatial modeling tools for estimating contaminant loads from septic systems to streams and rivers. The new scientific understanding and tools will be applied by the Partner Organizations to make informed decisions on septic system management programs and policy. While the project work is focused on Ontario, the findings are broadly relevant for evaluating and managing contaminant loading from septic systems across Canada. The project will train 4 graduate students and 4 undergraduate students and also build the knowledge and expertise of key staff at MECP and OOWA. All research trainees will receive world class training and gain valuable real world experience in an equitable, diverse and inclusive training environment.