Procedural Injustices in Drinking Water Policies? The Safe Drinking Water Act Examined

Access to clean drinking water for low-income and minority communities in the US has only recently gained importance as a research area. In California's Central Valley, our previous research indicated that small community water systems serving higher fractions of people of color and renters had higher concentrations of nitrates. These findings suggest a disproportionate exposure to a drinking water contaminant linked with reproductive toxicity and methemoglobinemia. But why do these inequalities persist in spite of the Safe Drinking Water Act (SDWA)? This study assesses the implementation rather than the intent of the SDWA. We examine whether procedural inequalities exist alongside distributional ones—whereby the regulatory structure that is meant to protect public health instead exacerbates disproportionate exposures. Using data on drinking water quality monitoring, historical rates of violations of maximum contaminant levels (MCL) and interviews with regulators, our study answers the following related questions: 1) do systems with higher percentages of minority and lower income populations monitor nitrate levels less frequently than required, and 2) do these systems have lower rates of nitrate MCL violations? Our preliminary results find a negative association between poverty (p<.01) and renter status (p<.0001) and the likelihood of nitrate monitoring, and that poverty mediates the association between race and violations. Furthermore, they also indicate that various types of procedural injustices exist along the chain of implementation of the SDWA, placing the public's health at risk, and indicating where the SDWA is flawed in its ability to meet its health mandate.