Managing Uncertainty in the Provision of Safe Drinking Water

Principal Investigator - Steve E. Hrudey, Professor Emeritus, University of Alberta

Drinking water providers and regulators share the responsibility of safeguarding public drinking water supplies, facing many complex issues in doing so. To ensure the delivery of high quality drinking water, regulatory and management systems collectively focus on the best response to address these challenges and manage uncertainties. Yet, water purveyors make these decisions without the benefit of an over-arching approach to characterize and compare risks, which would allow for the consideration of local priorities. The purpose of this project was to propose a common framework and management approach that can be used by drinking water providers and regulators to address risk and uncertainty for the guarantee of safe drinking water.


This state-of-the-knowledge synthesis study aimed to establish how science can be applied to decisions related to safe drinking water. After an initial appraisal, it was decided that two synthesis studies would be conducted to cover the separate issues of public health and ecological health, at which point the parallel reviews would be brought together to consider integrated water management approaches. Based on scientific evidence and rational analysis, the reviews examined how the goals of safe public water and a healthy environment are managed in the face of numerous and inevitable uncertainties.

An advisory committee was established to assist in project framing and the development of a longer term strategy to balance human and environmental health risks. Based on feedback from advisory committee members, a high-level team of international science experts worked on filling out the framework. Other organizations conducting high-level synthesis work in similar areas were identified to avoid potential overlap and recognize synergies and opportunities to incorporate or link to parallel work on risk management. After appropriate consultations, draft framework and summary documents were developed and distributed for feedback, the comments of which were incorporated into a final report.

  • Summary report: Managing Uncertainty in the Provision of Safe Drinking Water
  • A number of tools were developed to support water providers and regulators in their decision-making, including background information and case studies about risk, uncertainty and risk hierarchies; an outline of what contributes to making an informed consumer; rationale for strategic water quality monitoring; and an outline for a public communication strategy about health risk
  • By providing a common conceptual approach to dealing with challenges, one of the intended outcomes of the project was to reduce the occurrence of professionals ‘talking past one another’ in discussions on how to effectively implement drinking water standards
  • Informing water supply management decisions may improve conceptual understanding of practices, guidelines and actions related to health risk, as well contextualize management or regulatory decisions
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research team and partners:

Research Team

Steve Hrudey, Professor Emeritus, University of Alberta
Joan Rose, Homer Nowlin Chair in Water Research, Michigan State University
John Fawell, Visiting Professor, Cranfield University
Martha Sinclair, Senior Research Fellow, Monash University
William Leiss, Adjunct Professor, University of Ottawa



Managing Uncertainty in the Provision of Safe Drinking Water Website Hrudey