Disparities in community water systems' compliance with the Safe Drinking Water Act

Understanding potential disparities in communities' compliance with the Safe Drinking Water Act (SDWA) will help managers effectively and fairly allocate finding for improving drinking water systems. This study investigated the relationship between socioeconomic status and race, and violations to the SDWA by community water system (CWS) in the state of Pennsylvania. The sociodemographic characteristics of the water systems were estimated using three different CWS-level spatial analysis methods (areal weighting, dasymetric mapping, areal interpolation) and a county-level spatial analysis method. Negative binomial regression was then applied to determine if these sociodemographic characteristics, and other water system variables, are associated with the number o f total and/or health-based SDWA violations. Conclusive evidence of environmental injustice in SDWA violations by race or class was not found; however, this study did determine that small, rural CWSs are likely to have more violations than other CWSs. This research demonstrates that the spatial analysis method selected for an environmental justice study can affect the results and conclusions of the research.