COVID-19 Wastewater Surveillance

Tracking the prevalence of COVID-19 among metro area residents

What you flush down the toilet has a lot to say about the SARS-CoV-2 virus that causes COVID-19.

People infected with the virus shed it in their feces, even if they don’t have symptoms. The virus can be detected in wastewater and serve as an early warning sign that COVID-19 is spreading within a community.

Wastewater surveillance is a tool in public health decision making and establishing mitigation strategies, especially given home testing that goes unreported. It also lays the groundwork for monitoring for other infectious diseases.

Working with the U of M Genomics Center

In the Twin Cities metro area, scientists in our Environmental Services division partner with the University of Minnesota Genomics Center to extract and analyze viral genetic material, RNA, from wastewater flowing to the Metro Plant in Saint Paul.

By measuring the concentrations of the viral RNA in samples, they can assess the prevalence of the virus, the viral load, among the nearly two million people who live in the Metro Plant sewershed, the area of the region that the large treatment plant serves.

Wastewater sampling does not confirm individual cases or provide detailed information about how and where outbreaks occur. But it is an unbiased measure of disease prevalence in a sewershed.

Tracking COVID-19

The Met Council shares information on the virus and its growing number of variants with national and local partners, including the Minnesota Department of Health and University of Minnesota Medical School. Viruses like SARS-CoV-2 continue to change and mutate as they circulate.

See an interactive version of this information.

Wastewater surveillance addresses need for public health data

The Met Council samples wastewater flowing into four of the region’s nine treatment plants. The most prevalent data come from the Metro Plant, which treats the wastewater of 66 communities in five counties. Scientists there initially launched the initiative to be of assistance to the health department in the fight against COVID-19.

For more information on wastewater surveillance for SARS-CoV-2, visit the CDC website.