Nicholas Ashbolt, PhD, BAgSc (Hons)

Professor, School of Public Health


Professor, School of Public Health
(780) 492-5227
3-57D South Academic Building
11328 - 89 Ave NW
T6G 2J7



I focus on next-generation municipal water services (drinking water, wastewater, stormwater) framed around resource recovery (i.e. water, energy, fertilizers) for improved ecohealth and living conditions; integrated with quantitative microbial risk assessment (QMRA) to identify research gaps and management targets. Current topics include water system management (treatment performance, post-treatment control of opportunistic pathogens) from a public health perspective:

  1. Premise plumbing biofilms and environmental pathogens; identification of novel respiratory pathogens and their amoebal hosts by application of microarrays, metagenomic analysis and qPCR in collaboration with the U.S. EPA and Alberta Health.
  2. Antibiotic-resistance (resistome) gene flow within reclaimed water biofilms (qPCR and metagenomic) in hospitals.
  3. Application of QMRA to interpret the above and focus management options and regulatory reform (Health Canada).
  4. Integration of human health with ecosystem/LCA and economic analyses to identify more sustainable municipal water services; working with and to inform private and government housing developers.


PhD, University of Tasmania, 1985
BAgSc(Hons), University of Tasmania, 1979


Bronze Award for science at ORD, U.S. Environmental Protection Agency, 2008, 2012 & 2013 
Graduate Award for professional outreach/impact, University of Tasmania, 2007

community acquired pneumonia 
in-premise plumbing microbiome
Legionella-like bacteria
quantitative microbial risk assessment
water-based pathogen removal


Research collaborations with other academic institutions:

  • McGill University, Canada
  • Norwegian University of Life Sciences, Norway
  • University of New South Wales, Australia
  • University of Technology, Australia

Collaborations with non-governmental organizations:

  • American Water Works Association, USA
  • Canadian Water Network, Canada
  • International Standards Association/ International Code Council/Canadian Standards Association, Canada, China & USA
  • International Water Association, UK
  • National Water Reuse Institute, USA
  • The Water Research Foundation, USA
  • World Health Organization, Switzerland

Collaborations with governmental organizations:

  • Alberta Environment and Parks, Canada
  • Alberta Health and Alberta Health Services, Canada
  • Alberta Municipal Affairs, Canada
  • City of Calgary, Canada
  • EPCOR, Canada
  • Health Canada, Canada
  • United States Environmental Protection Agency, USA



Not currently accepting students.

Scholarly Activities

Research - Control options for premise plumbing opportunistic pathogen exposures

Principal Investigator

Funded by NSERC Discovery Grant

Understanding aerosolization of enteric and respiratory pathogens in premise plumbing.

Research - Developing a Framework for Wastewater Reuse in Canada: Using Quantitative Microbial Risk Assessment, Risk Communication, and Community Engagement for Evaluating Water-Fit-For-Purpose Reuse

Principal Investigator

Funded by Canadian Institutes of Health Research Team Grant: Environments and Health

Developing risk targets for enteric and saprozoic pathogen control and roadmap to guide societal ‘pull’ for water reuse projects within Canadian communities.

Research - Evaluating Microbial Risks Associated with Stormwater Management and Reuse in Alberta

Co-principal Investigator

Funded by Alberta Innovates Grant and NSERC Collaborative Research and Development Grant

Assessing faecal contamination sources and level of treatment fit-for-purpose uses by apply QMRA.

Research - forWater: NSERC Network for Forested Drinking Water Source Protection Technologies

Co-Principal Investigator

Funded by NSERC Network Grant

Investigating potential impacts of forest fires in drinking water catchments on distributed water biofilm pathogens.

Research - Strategies to Improve Ammonia removal from ammonia-rich Sludge Liquor in Canada

Co-Principal Investigator with Dr. Yang Liu (Civil and Environmental Engineering)

funded by NSERC as a Collaborative Research and Development grant with EPCOR Water Services Inc.


Antimicrobial Resistance: Fecal Sanitation Strategies for Combatting a Global Public Health Threat

Author(s): Ashbolt, N. J.; Pruden, A.; Miller, J. H.; Riquelme, M. V.; Maile-Moskowitz, A.
Publication Date: 2018
Publication: Global Water Pathogens Project

Free-living amoebae supporting intracellular growth may produce vesicle-bound respirable doses of Legionella within drinking water systems.

Author(s): Shaheen, M.; Ashbolt, N. J.
Publication Date: 2018
Publication: Exposure and Health 2018
Volume: 10
Issue: 3
Page Numbers: 201-209

Persistence of infectious Enterovirus within free-living amoebae – A novel waterborne risk pathway?

Author(s): Atanasova, N. D.; Dey, R.; Scott, C.; Li, Q.; Pang, X.-L.; Ashbolt, N. J.
Publication Date: 2018
Publication: Water Res
Volume: 2018
Issue: 144
Page Numbers: 204-214

Twenty five years of beach monitoring in Hong Kong: A re-examination of the beach water quality classification scheme from a comparative and global perspective

Author(s): Thoe, W., O.H.K. Lee, K.F. Leung, T. Lee, N.J. Ashbolt, R.R. Yang, S.H.K. Chui
Publication Date: 2018
Publication: Marine Pollution Bulletin
Volume: 131
Page Numbers: 793-803

Cost, energy, global warming, eutrophication and local human health impacts of community water and sanitation service options

Author(s): Schoen, M.E., X. Xue A. Wood, T.R. Hawkins, J. Garland, N.J. Ashbolt
Publication Date: 2017
Publication: Water Research
Volume: 109
Issue: 1
Page Numbers: 186-195

Effect of disinfectant exposure on Legionella pneumophila associated with simulated drinking water biofilms: release, inactivation, and infectivity

Author(s): Shen, Y., C. Huang, J. Lin, W. Wu, N.J. Ashbolt, W.T. Liu, T.H. Nguyen
Publication Date: 2017
Publication: Environmental Science and Technology
Volume: 51
Issue: 4
Page Numbers: 2087-2095

Risk-based enteric pathogen reduction targets for non-potable and direct potable use of roof runoff, stormwater, greywater, and wastewater

Author(s): Schoen, M.E., N.J. Ashbolt, M.A. Jahne, J. Garland
Publication Date: 2017
Publication: Microbial Risk Analysis
Volume: 5
Page Numbers: 32-43

UV disinfection of hand-rinse greywater and performance testing using indigenous Staphylococcus spp

Author(s): Shoults, D.C., N.J. Ashbolt
Publication Date: 2017
Publication: Water
Volume: 9
Issue: 12

Microbial contamination of drinking water and human health from community water systems

Author(s): Nicholas J. Ashbolt
Publication Date: 2015
Publication: Current Environmental Health Reports
Volume: 2
Issue: 1
Page Numbers: DOI: 10.1007/s40572-014-0037-5

An in-premise model for Legionella exposure during showering events

Author(s): Schoen, M.E. and Ashbolt, N.J.
Publication Date: 2011
Publication: Water Research
Volume: 45
Issue: 18
Page Numbers: 5826-5836