PHAC Wastewater Surveillance Program for COVID-19

May 3, 2023

The virus that causes COVID-19 infection (SARS-CoV-2) can be detected in the stool of infected people over a significant portion of their illness. This provides an opportunity to test and monitor wastewater (sewage) for the presence of COVID-19 in communities and institutional settings (e.g. long-term care facilities) without the need for individual testing. Wastewater surveillance can also be used to monitor the circulation of variants of concern (VOC) and, in some circumstances, can be used as an early indicator for the presence of COVID-19 infections not yet detected by traditional clinical surveillance.

The Public Health Agency of Canada (PHAC) is working in collaboration with other federal departments, provincial, territorial and municipal governments and academia across Canada to establish a pan-Canadian wastewater surveillance network capable of monitoring the spread of COVID-19 in Canada (see Map and Critical Path documents). Wastewater has already been used to show early detection of COVID-19 in some Canadian jurisdictions prior to an increase of clinically diagnosed cases. As COVID-19 can be characterized by symptomatic and asymptomatic infection, it is important to identify the presence of undiagnosed cases to minimize the likelihood of outbreaks. Even a few days of early warning can be critical to the success of public health interventions and can be an important source of information for public health action.

In addition to COVID-19, wastewater surveillance can be used to monitor other public health threats, including the presence of antimicrobial resistance, additional communicable diseases (e.g. Tuberculosis) and chemical markers indicating the health of a community (e.g. the use of opioids).

Wastewater Surveillance Map

Map of Pan-Canadian Wastewater Network

National Wastewater Surveillance Trends

The Public Health Agency of Canada has developed a dashboard to track and compare the COVID-19 levels in some major communities across Canada over time. This trend data is updated Tuesdays and Fridays every week and can be found here: COVID-19 Wastewater Surveillance Dashboard

Canadian Wastewater Survey (CWS)

Statistics Canada and PHAC have been collaborating on the Canadian Waster Survey (CWS) to conduct surveillance of wastewater samples for SARS-CoV-2 from various wastewater treatment plants in five cities across Canada (Halifax, Montréal, Toronto, Edmonton, and Vancouver) since September 2020.

Wastewater Surveillance Reports/Trends:

For more information on the CWS please see the following links:

City of Winnipeg, Manitoba Trend Reports

PHAC is working with the city of Winnipeg and the province of Manitoba to conduct wastewater surveillance for SARS-CoV-2 in the city’s three wastewater treatment plants. 

Wastewater Surveillance Reports/Trends:

City of Regina, Saskatchewan Trend Reports

PHAC is working with the Saskatchewan Health Authority, University of Regina and EPCOR Water Prairies to conduct wastewater surveillance for SARS-CoV-2 in the city of Regina’s wastewater treatment plant.

Wastewater Surveillance Reports/Trends:

City of St. John’s, Newfoundland and Labrador Trend Reports

PHAC is working with the Government of Newfoundland and Labrador to conduct wastewater surveillance for SARS-CoV-2 in the city’s wastewater treatment plant.

Wastewater Surveillance Reports/Trends:

Canadian Wastewater COVID-19 Surveillance Dashboards or Websites


Centre for Health Informatics Dashboard

British Columbia

Metro Vancouver COVID-19 Wastewater Dashboard

Newfoundland and Labrador

Newfoundland and Labrador Wastewater Surveillance Report

Northwest Territories

Northwest Territories COVID-19 Dashboard


Ontario Science Table Dashboard

Brant County Health Unit Dashboard

City of Greater Sudbury Dashboard

Durham Region COVID-19 Wastewater Surveillance

Eastern Ontario Health Unit Dashboard

Halton Region Dashboard

Hamilton Public Health Services Dashboard

Haliburton, Kawartha, Pine Ridge District Health Unit Dashboard

Kingston, Frontenac, Lennox, and Addington Public Health Dashboard

Leeds, Grenville and Lanark District Health Unit Dashboard

Ottawa Public Health Dashboard

Region of Peel – Public Health Weekly Report

Region of Waterloo Dashboard

Simcoe Muskoka District Health Unit Dashboard

Thunder Bay District Health Unit Dashboard

Toronto Public Health Wastewater Report

Wellington-Dufferin-Guelph Public Health Dashboard

Windsor-Essex County Dashboard

York Region Dashboard


The CentrEau-COVID Pilot Project Dashboard


University of Saskatoon Dashboard

Current and Past Webinars

  • PHAC hosted a Webinar entitled “Moving SARS-CoV-2 signals in Wastewater to Public Health Action” on April 1, 2021. Presentations covered laboratory methods, public health interpretation survey results, and two case studies (Ottawa and Northwest Territories).
  • The Health Canada Testing, Contact Tracing, and Data Strategies secretariat and Public Health Agency of Canada organized a joint Knowledge Exchange session on ‘Wastewater surveillance in Canada – Lessons Learnt’ on September 27, 2021. The presentations covered lessons learnt from surveillance of SARS-CoV-2 in wastewater collected at wastewater treatment plants or further upstream at facility level.

Publications and Reports

  • Arts et al. (2022) – Community Surveillance of Omicron in Ontario: Wastewater-based Epidemiology Comes of Age
  • Barker at al. (2021) – MMMVI: Detecting SARS-CoV-2 variants of concern in metagenomic samples
  • Champredon et al. (2022) – Emergence and spread of SARS-CoV-2 Variants of Concern in Canada: A retrospective analysis from clinical and wastewater data
  • Chik et al. (2021) – Comparison of approaches to quantify SARS-CoV-2 in wastewater using RT-qPCR: Results and implications from a collaborative inter-laboratory study in Canada
  • Daigle et al. (2022) – A sensitive and rapid wastewater test for SARS-COV-2 and its use for the early detection of a cluster of cases in a remote community
  • Fuzzen et al. (2022) – Multiplex RT-qPCR assay (N200) to detect and estimate prevalence of multiple SARS-CoV-2 Variants of Concern in wastewater
  • Joung et al. (2022)– Coupling Wastewater-Based Epidemiological Surveillance and Modelling of SARS-COV-2/COVID-19: Practical Applications at the Public Health Agency of Canada
  • Landgraff et al. (2021) – Metagenomic sequencing of municipal wastewater provides a near-complete SARS-CoV-2 genome sequence identified as the B.1.1.7 variant of concern from a Canadian municipality concurrent with an outbreak
  • Manuel et al. (2021) – The role of wastewater testing for SARS-CoV-2 Surveillance
  • Nourbakhsh et al. (2021) – A wastewater-based epidemic model for SARS-CoV-2 with application to three Canadian cities
  • Peterson et al. (2022) – RT-qPCR detection of SARS-CoV-2 mutations S 69-70 del, S N501Y and N D3L associated with variants of concern in Canadian wastewater samples
  • Xie et al. (2022) – RNA in Municipal Wastewater Reveals Magnitudes of COVID-19 Outbreaks across Four Waves Driven by SARS-CoV-2 Variants of Concern

Guidance Document for Wastewater Surveillance

Environment and Climate Change Canada, Wastewater Science Unit: 

Public Health Agency of Canada:

Ontario – Ministry of the Environment, Conservation and Parks:

Public Health Agency of Canada Wastewater Working Groups and Meetings

The Public Health Agency of Canada is leading working groups and meetings related to wastewater surveillance for COVID-19 to discuss sampling, laboratory methods, data models, modelling and public health action and response.  There are currently four working groups and meetings held regularly:

SARS-CoV-2 Variants of Concern in Wastewater

This working group brings together researchers, academic and government partners across Canada working on wastewater surveillance to discuss the detection of variants of concern/interest in wastewater and interpretation of results.  The meeting highlights key issues related to variants of concern/interest detection and sequencing and all laboratories or surveillance programs across the country to provide an update and share their experiences.   

Wastewater Laboratory Detection of SARS-CoV-2 Working Group

This working group brings together laboratories across Canada conducting wastewater testing and surveillance for SARS-CoV-2 to discuss methods (e.g. PCR, QA/QC), sampling issues, data interpretation, reporting of results, and any other topics related to laboratory methods for detection.

Wastewater SARS-CoV-2 Surveillance Updates

This working group brings together wastewater surveillance partners across the country to create a forum for moving wastewater surveillance to public health action. This working group builds the connections between environmental sampling groups, laboratories, academia and public health to discuss sampling strategies, data interpretation and public health reporting and action.

Data Modelling and Epidemiological Interpretation Working Group

This working group brings together modellers and epidemiologists from all levels of government and academia to discuss modelling, modelling methods and interpretation of wastewater surveillance results as they relate to clinical surveillance. 

Connect with Us

For any inquiries or to attend any of these meetings, please contact: