Approximately 48 million people in the US are served by private and frequently untreated wells.Crudely, we estimate that 1.3 million cases of acute gastrointestinal illnesses (AGI) per year are attributed to consuming water from untreated private wells in the US. Well-water associated AGI causes significant burden in terms of health care costs and lost work/ school days, as well as increased risk to developing longer term health complications.This impact is magnified when accounting for vulnerable populations such as children under the age of 5, the elderly and the immune-compromised.

Private water supplies in the US are unregulated; homeowners are responsible for testing and treating their water. There is growing evidence that even deep groundwater supplies (including my own) can be contaminated with human pathogens. Our research in this area involves working at the interface of epidemiology, microbiology, water quality and treatment, geology and mathematical modeling to understand transport mechanisms of pathogens in groundwater from septic systems and the risk to public health. We also seek to understand the policy challenges associated with supporting households in the sustainable management of private water supplies in the US. This work will help identify the vulnerabilities of groundwater water supplies as a result of ageing infrastructure, inadequate treatment, and extreme weather events and help to inform policy decisions on the management of private wells. This work has been funded by: the National Institutes of Health and the US Geological Survey.