Two Drinking Water Studies Published by National Academy of Sciences


Two drinking water studies were recently published in the Proceedings of the National Academy of Sciences. A study on national trends in drinking water violations found widespread violations of health-based standards, with 9-45 million people possibly affected during each of the 34 years in the study (1982-2015). The study identified hot spots (higher numbers of violations) across the country, as well as vulnerability factors associated with violations. Rural areas were more vulnerable, as the study found violation incidence in rural areas to be substantially higher than in urban areas. ASDWA is working with the lead author of the study, Dr. Allaire from the University of California-Irvine, to schedule a webinar for ASDWA members in late March in order to learn more about details of this study and facilitate some discussion on how some of the policies recommended in the study might be implemented by states. Additionally, in EPA’s FY 2018-2022 Strategic Plan, goals for lowering the number of health-based violations have been established.

The second study assessed the Legionnaires’ disease (LD) outbreak in Flint. The study evaluated the free chlorine concentrations and the 2014-2015 LD outbreak in Genesee County, MI, where Flint is located. The study found that the risk of a Flint resident contracting LD increased 6.3 fold following the change in raw water supplying Flint in 2014. Additionally, the study found the risk increased as chlorine concentrations decreased – the risk increased by 80% per 1 mg/L decrease in free chlorine during this change.