High-resolution Analysis of Demographic and Socioeconomic Characteristics of Households with Private Wells in the USA

Abstract

Private domestic wells supply drinking water to roughly 15% of the United States population, yet remain largely unregulated, and poorly characterized in terms of the populations they serve. While prior national studies describe broad patterns of domestic well use, they are generally limited to coarse regional resolutions or smaller geographic extents. Here, we present a national, high-resolution analysis of the demographic and socioeconomic profiles of households with private wells in the United States. We integrate geospatial data from a national database of groundwater wells with block- and block group- level demographic information from the 2020 U.S. Census and American Community Survey. Domestic wells are identified and spatially linked to population characteristics including race, educational attainment, and household income, with results aggregated to the county level. We further stratify findings by urban-rural classification to examine patterns across population density gradients. Our analysis revealed substantial spatial variation in the demographic characteristics of well users as compared to nonwell users. Overall, well users are more likely than their public water counterparts to identify as White and to reside in households with higher incomes than county medians. Differences in educational attainment are more variable across states and counties, but are generally modest in magnitude. Across counties, increases in educational attainment and in the proportion of White-identifying well users are associated with higher household incomes. These findings provide a demographic context for domestic well reliance and may support the development of more targeted policies and resources for domestic testing, treatment, and maintenance for populations dependent on private wells.