One PFAS: A One Water Approach to Managing PFAS Pollution

Per- and polyfluoroalkyl substances (PFAS) pollution has emerged as a major public health and environmental challenge, particularly for drinking water systems. The Occoquan Reservoir, a principal source of drinking water for up to one million residents in Northern Virginia, has perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) concentrations above U.S. EPA maximum contaminant levels (MCLs). These “forever chemicals” persist in the environment, resist degradation, and have been linked to adverse human health effects, including cancer, immune system dysfunction, and developmental issues. Addressing PFAS contamination in this complex One Water system, which integrates drinking water, wastewater, and stormwater management, requires a coordinated and innovative approach.

This project develops the generalizable modeling tools, data on PFAS sources and their relative contributions at a watershed scale, and resources needed to identify, quantify, and ultimately control PFAS pollution in this and other One Water systems. The One Water framework in this study promotes collaboration among stakeholders responsible for different parts of the water cycle and facilitates a holistic watershed management and source water protection strategy that integrates monitoring, treatment, and source control. By adopting a comprehensive One Water approach to PFAS management, the watershed stakeholders can optimize mitigation measures across subsystems to minimize costs while maximizing public health and water quality benefits at a watershed scale.