Social vulnerability and exposure to private well water

One quarter of the population of Pennsylvania relies on private domestic well water: two-fold greater than the US average. Private well owners are responsible for the maintenance and treatment of their water supply. Targeted interventions are needed to support these well owners to ensure they have access to safe drinking water, free of contaminants. To develop appropriate interventions, an understanding of the characteristics and social vulnerability of communities with high well water use is needed. The purpose of this study was to determine the spatial patterning of social vulnerability in Pennsylvania and assess the association between social vulnerability and private domestic wells using profile regression. Census data and water supply information were used to estimate the proportion of the population using domestic wells. Ten area-level measures of social vulnerability at the census-tract level were investigated, using Bayesian profile regression to link clustering of social vulnerability profiles with prevalence of private domestic wells. Profile regression results indicated 15 distinct profiles of social vulnerability that differ significantly according to the area-level prevalence of domestic well use frequency. Out of these, two profiles of census tracts were identified as socially vulnerable and had a high proportion of well-water users, representing approximately 1.1 million Pennsylvanians or a third of all well water users in the State. High area-level social vulnerability profiles coincide with a high frequency of private well-water use in PA. This study presents a data-driven approach to supporting public health programs aimed at reducing exposure and health risks of chemical and infectious agents in household water supplies by targeting vulnerable populations.