Microbial analyses of water from private wells in southwestern Wisconsin, 2019 to 2020.

Private wells (n = 138) were sampled by large- and small-volume sampling methods in Grant, Iowa, and Lafayette Counties, Wisconsin, USA in 2019 and 2020. Well water samples were analyzed for microorganisms by quantitative polymerase chain reaction at the Laboratory for Infectious Disease and the Environment (LIDE). Gene targets for viruses, bacteria, and protozoa were analyzed, including pathogens and microbial source tracking markers. Data were collected to characterize microbial contamination of private well water to better understand water quality and potential causes of contamination. Collaborators include U.S. Department of Agriculture-Agricultural Research Service; Wisconsin Geological and Natural History Survey; and Grant, Iowa, and Lafayette Counties, Wisconsin.