Positive trend: COVID-19 levels in Yorkville sewage down to ‘flat zero’

After monitoring COVID-19 levels in wastewater for seven months, no traces of the virus were detected in Yorkville sewers last week, the Yorkville-Bristol Sanitary District announced Monday, June 28.

The sanitation district has monitored the virus’ prevalence in wastewater since Thanksgiving as lab testing became more widespread and affordable. People begin shedding COVID-19 through their urine and feces even before they’re contagious, making wastewater an ideal tool for tracking the virus’ spread.

“Since the beginning of June, it’s been incredibly low,” Cyrus McMains, executive director of the sanitation district, said of the sewer data.

Recent samples registered lower than the testing’s sensitivity levels, but last week’s data was a first for the program.

“The one today, we actually got a flat zero,” McMains said.

Although there’s less viral load to track, the district’s testing data has largely tracked alongside state and nationwide case counts. For testing, the district ships water samples from its facility to a third-party lab operated by Colorado-based GT Molecular, similar to a COVID-19 testing program operated by the Fox Metro Water Reclamation District.

“Across the nation, we are seeing low levels and overall trends downward, but YBSD appears to be leading with only a few other communities to levels below our ability to detect,” said Dr. Rose Nash, director of research and development at GT Molecular.

As for the future of testing Yorkville sewers for the virus, McMains said the district board will decide in the coming months whether to extend the program. With COVID-19 variants prolonging concerns about the pandemic, the district’s executive director said that viral mutations could make continued wastewater testing worthwhile.

“What we can sample in the wastewater and the information it tells us is pretty remarkable,” McMains said.