As EPA maximum contaminant levels for PFAS take effect, municipal water utilities across the United States are investing in treatment upgrades. Understanding what technologies are being deployed at the utility scale illuminates the broader picture of PFAS management and helps communities assess their water system’s capabilities.
Granular Activated Carbon at Scale
Granular activated carbon (GAC) contactors are the most widely adopted municipal PFAS treatment technology. Large vessels containing thousands of pounds of GAC media treat high flow rates continuously. When media approaches saturation, it is removed and either regenerated thermally or replaced. Municipal GAC systems typically achieve PFOA and PFOS reduction of 95 percent or greater when properly sized and managed.
High-Pressure Membrane Systems
Nanofiltration and reverse osmosis are being installed at larger utilities where high PFAS concentrations or stringent treatment goals make membrane technology cost-effective. Membrane systems can achieve the very low effluent concentrations required by new EPA limits but involve higher capital costs and produce a concentrate stream requiring disposal management.
Ion Exchange at Municipal Scale
PFAS-selective anion exchange resins are increasingly deployed at utilities, particularly where short-chain PFAS compounds are a concern. Single-use resin systems avoid regenerant management complications and provide strong performance across a wider range of PFAS compounds than GAC alone.
Combination Approaches
Many utilities are implementing multi-barrier treatment trains combining technologies — for example, coagulation and sedimentation to remove particles, followed by GAC for PFAS, followed by UV disinfection. This layered approach addresses multiple contaminants simultaneously while meeting PFAS limits reliably across seasonal variation in source water quality.