Lewis & Clark Public Health explains Helena COVID wastewater testing results

COVID Wastewater Testing
Posted at 6:00 PM, Aug 31, 2021
and last updated 2021-08-31 20:40:22-04

HELENA — Earlier this month, Lewis and Clark Public Health issued a warning after an “unprecedented” rise in the amount of coronavirus detected in Helena’s wastewater system. But after that, the numbers have varied dramatically. Public Health leaders say they’re considering multiple explanations for what could have led to these shifting statistics.

For more than a year, LCPH has been partnering with Carroll College to test how much of the virus can be found in Helena and East Helena wastewater. Leaders say that gives a picture of how widespread COVID-19 is in the community, without relying on people getting tested.

On Aug. 9, LCPH reported a massive spike in Helena’s system, from 16,000 copies of the virus per liter to 193,000 copies per liter – in just one week. That was by far the highest they’ve seen so far. The previous high was 63,000 copies per liter in December.

“We questioned the results of 193-thousand per genomic liter a couple weeks ago,” said Lewis and Clark County health officer Drenda Niemann. “Carroll College ran that again to confirm that that was an accurate reading.”

However, the next week, the number fell to 38,000 per liter – a significant drop, but still higher than any time since last winter. The week after, it spiked again, to 93,000 per liter.

Niemann said they’re considering a number of factors that could have contributed to the first extreme increase.

“That was about the same time that we had an influx of tourists in the community around the Stampede,” she said. “There could have been an impact of septic pumpers; it’s not uncommon for septic pumpers taking septic system waste from the county into the city and disposing of it into the city system.”

But regardless of the specific changes in the numbers, Niemann said the overall trend confirms COVID is still very prevalent in the Helena community. She asked the public to continue to take precautions against the virus.

“The virus is here, we have a significant increase in cases, our hospital is severely impacted, and we need individuals in this community to do the right thing,” said Niemann.

East Helena’s wastewater testing showed a different pattern than Helena’s. On Aug. 9, virus levels there appeared to dip. They then spiked the next week and dipped again the week after. Like Helena, though, the overall numbers remain the highest they have been since last winter.

Several weeks ago, Lewis and Clark County allocated $35,200 in American Relief Plan Act money to continue COVID-19 wastewater testing through next year.