ST. PAUL, Minn. - There may be viruses and bacteria in some of the wells that supply drinking water to Minnesotans, according to a study requested by the state Legislature.

The Minnesota Department of Health (MDH) said Friday that scientists have found evidence of genetic materials like DNA in water from some public wells. The researchers are only one year into a two-year study, and they said more testing is needed to determine whether there's a health risk for the people drinking the water.

MDH said finding these microbes doesn't necessarily mean the water will make people sick. It does mean that the system may be vulnerable to contamination.

Once the study is finished, MDH said it might recommend improving prevention measures, repairing or replacing some wells, or adding disinfection to the water treatment process.

The final report will take months, but MDH says system owners with vulnerable wells are being notified so they can "assess their wells, look for solutions and inform their customers."