This week, Wisconsin Governor Tony Evers signed into law updates to the state’s 2022 drinking water standards of 70 parts per trillion (ppt) to align with federal limits for PFAS to a new enforceable standard of 4.0 part per trillion (ppt) for certain contaminants. The Wisconsin Natural Resources Board approved these standards in January.
The Wisconsin Department of Natural Resources (DNR) and the Governor began the rulemaking process by submitting a scope statement to amend the current drinking water standards to reflect the new federal maximum contaminant levels for PFOA and PFOS and include water standards for perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluorobutane sulfonic acid (PFBS), and hexafluoropropylene oxide dimer acid (HFPO-DA), for which Wisconsin does not currently have standards.
Because of the existing state PFAS drinking water standards, Wisconsin has the benefit of PFAS sample results from all of its public water systems that will be regulated by the federal PFAS rule. The state estimates that 96 public water systems will need to take action to address current PFAS by April 26, 2029 based on current sample results. Wisconsin DNR will provide assistance with compliance.
