Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/5/2021
Publication Date: 10/5/2021
Citation: Burch, T.R. 2021. Quantitative microbial risk assessment for contaminated private wells in the fractured dolomite aquifer of Kewaunee County, Wisconsin. Meeting Abstract. Land and Water Conservation Board meeting.
Technical Abstract: Private wells are an important source of drinking water in Kewaunee County, Wisconsin. Due to the region’s fractured dolomite aquifer, these wells are vulnerable to contamination by human and zoonotic gastrointestinal pathogens originating from land-applied cattle manure and private septic systems. However, the magnitude of the health burden associated with this contamination is unknown. This study combined quantitative microbial risk assessment (QMRA) with a year-long county-wide pathogen occurrence study in order to predict total cases of acute gastrointestinal illness (AGI) caused by private well contamination in the county. It also used microbial source tracking to associate predicted cases with bovine, human, or unknown fecal sources. Results suggest that private well contamination could be responsible for as many as 301 AGI cases yr-1 in Kewaunee County, and that 230 cases yr-1 were associated with a bovine fecal source (human: 12 cases yr-1, unknown: 59 cases yr-1). Furthermore, Cryptosporidium parvum was predicted to cause 190 cases yr-1, the most out of all 8 pathogens included in the QMRA. These results have important implications for land use and water resource management in Kewaunee County and inform the public health impacts of consuming drinking water produced in other similarly vulnerable hydrogeological settings.