Study finds small public wells in Minnesota have viruses, bacteria.
ST. PAUL — Bacteria and viruses that could make people sick have been discovered in small public drinking water wells across the state, according to a report released Friday by the Minnesota Department of Health.
The study, ordered by the state Legislature in 2014, found that, while the overall presence of microbial indicators in samples was low, a high percentage of wells had at least one detection.
But 37 percent of systems had DNA-like evidence of human viruses and 89 percent of systems had evidence of microbes, including some that don’t cause human illness, detected at least once.
They also don’t know if there is any widespread human health risk for people drinking from wells that test positive — whether people drinking that water are getting sick.
“That’s part of the work we still have to do: looking at the wells, potential sources of contamination and other factors, and figuring out how the contamination is occurring and what can be done about it.” None of the wells involved serve municipal water supply systems — those larger systems require treatment to kill viruses and bacteria.
There are about 1,500 of those small, public systems across the state that don’t treat their water, officials said Friday.
Finding such evidence of microbes in a drinking water system does not necessarily mean that those consuming water from these systems would become ill. “We continue to analyze the results of the study to get a better sense of the potential risk,” said Paul Allwood, assistant state health commissioner, in a statement Friday.
The 2014 Minnesota Legislature directed the Health Department to conduct a groundwater virus monitoring project using funding from the state’s Clean Water Fund.
The Health Department recommends that both public and private water systems continue to maintain their wells and conduct routine testing of their water supply.