The geography and socioeconomic characteristics of U.S. households reliant on private wells and septic systems

Households reliant on unregulated, non-grid water and sanitation infrastructure, like private wells and septic systems, face water quality and reliability deficiencies and associated negative impacts on human health at greater proportions than households reliant on publicly-regulated, water and sewage systems. This study uses the 2019 American Housing Survey to produce the first joint, nationally-representative analysis of household reliance on wells and septics in decades. We find that there are lower proportions of U.S. households off the regulated water grid than other contemporary estimates. We also find that while 9.1% of U.S. households rely on both private well and septics simultaneously, a slightly higher proportion of households rely on only one of these systems, with the companion infrastructure being publicly regulated. Our results show that both private well and septic reliant households are much more likely to be non-Hispanic White, live in a single family home (a detached or attached one-family dwelling) or mobile home (a portable habitable structure that was originally fitted with wheels to facilitate movement), and to live outside a metropolitan area than those reliant on publicly regulated service. Yet, surprisingly both private well and septic reliant households do not have lower average incomes than households reliant on regulated systems. These results suggest that federal, state and local financial assistance, technical assistance and educational programs can be better targeted to ensure that in-need private well and septic reliant households can operate and maintain their essential water and sanitation infrastructure.