Current Status
On May 18, 2026, EPA proposed two rules related to PFAS in drinking water. The first would rescind Biden-era regulations for PFHxS, PFNA, HFPO-DA, and Hazard Index mixtures. The second would extend the compliance deadlines for the PFOA and PFOS Maximum Contaminant Levels (MCLs) for two additional years, until 2031. The comment periods for each rule close July 20, 2026. EPA also announced a public hearing will be held on July 7, 2026 where the public can provide comments on the rules. The deadline for registration to attend or provide verbal public comment is July 1, 2026.
Why it Matters
PFAS, often called “forever chemicals,” are a family of man-made chemicals featuring a strong carbon fluorine bond that makes the chemicals extremely durable. Studies have found significant PFAS contamination in the country’s public drinking water supplies. At high levels of exposure, PFAS have been shown to cause serious human health problems.
The Biden-era PFAS rule under SDWA establishes deadlines for drinking water systems to test for PFAS by 2027 and to meet specific PFAS standards by 2029. The regulation is a significant step toward protecting public health as envisioned in EPA’s 2021 PFAS Strategic Roadmap.
Key Resources
Timeline
May 18, 2026 EPA proposed two rules related to PFAS in drinking water. The first would rescind Biden-era regulations for PFHxS, PFNA, HFPO-DA, and Hazard Index mixtures. The second would extend the compliance deadlines for the PFOA and PFOS Maximum Contaminant Levels (MCLs) for two additional years, until 2031. The comment periods for each rule close July 20, 2026. EPA also announced a public hearing will be held on July 7, 2026 where the public can provide comments on the rules. The deadline for registration to attend or provide verbal public comment is July 1, 2026.
April 6, 2026 EPA published its sixth draft Contaminant Candidate List (“CCL 6”) for public comment, which lists contaminants that are known or anticipated to occur in public water systems and may require regulation under the Safe Drinking Water Act (SDWA) in the future. PFAS were included on this list. EPA stated it will decide whether to regulate at least five contaminants from the CCL. Comments on CCL 6 are due June 5, 2026.
March 19, 2026 The D.C. Circuit denied EPA’s request to sever and hold in abeyance challenges to drinking water standards for four Index PFAS that the agency now intends to repeal. American Water Works Association, et al., v. EPA, No. 24-1188 (D.C. Cir.).
Feb. 19, 2026 EPA filed a motion to sever and hold in abeyance claims related to Index PFAS regulations in American Water Works Association, et al., v. EPA, No. 24-1188 (D.C. Cir.). In its motion, EPA stated it intends to “commence the rulemaking process imminently” to rescind the portion of the Biden-ERA PFAS drinking water rule that issues regulatory determinations and standards for the Index PFAS.
Jan. 12, 2026 The D.C. Circuit issued an order denying EPA’s previous request to summarily vacate four of the six Biden-era PFAS drinking water rules. The court explained that despite EPA’s arguments that the rules were procedurally inadequate, the merits of the parties’ positions were “not so clear as to warrant summary action.” American Water Works Association, et al., v. EPA, No. 24-1188 (D.C. Cir. June 07, 2024).
Sept. 11, 2025 EPA requested the D.C. Circuit vacate four of the six Biden-era PFAS drinking water rules, arguing that the agency failed to follow the Safe Drinking Water Act’s public comment procedures when issuing those standards. American Water Works Association, et al., v. EPA, No. 24-1188 (D.C. Cir.).
July 22, 2025 The D.C. Circuit granted EPA’s motion to reactivate the litigation regarding a challenge by industry and utilities to the Biden-era PFAS drinking water rule. American Water Works Association, et al., v. EPA, No. 24-1188 (D.C. Cir.).
May 14, 2025 EPA announced it will delay implementation of the SDWA Biden-era rule for two PFAS chemicals, PFOS and PFOA, extending the compliance deadline for drinking water suppliers to meet standards set for those two chemicals to 2031, providing water suppliers two additional years to comply. EPA also stated it will rescind the standards set in the Biden-era rule for four other PFAS chemicals. EPA expects to reissue a new regulation in spring 2026 and will continue to defend the other standards set in the Biden-era rule for PFOS and PFOA in the litigation challenging the rule. American Water Works Association, et al., v. EPA, (D.C. Cir. June 2024) Docket Number 24-1188.
April 28, 2025 EPA announced it intends to address PFAS contamination. EPA also stated it will address concerns raised by water providers regarding the timing of the SDWA PFAS rule’s drinking water standards and monitoring deadlines.
April 7, 2025 The court granted an unopposed EPA motion to extend the stay for 30 additional days. American Water Works Association, et al., v. EPA, (D.C. Cir. June 2024) Docket Number 24-1188.
Feb. 7, 2025 The Court agreed to grant EPA’s motion to hold the case in abeyance for 60 days while EPA reevaluates the Biden-era rule. American Water Works Association, et al., v. EPA, No. 24-1188 (D.C. Cir.).
June 7, 2024 Trade associations representing public water providers and industry challenged the EPA PFAS drinking water rule, arguing, among other issues, that EPA did not rely on the best available science, took unlawful novel approaches, and underestimated the costs of the regulation. Multiple environmental groups and 18 states have intervened in support of the rule. American Water Works Association, et al., v. EPA, No. 24-1188 (D.C. Cir.)., consolidated with other challenges to the rule.
April 26, 2024 EPA, under the Safe Drinking Water Act, finalized the PFAS National Primary Drinking Water Regulation Rule, setting drinking water standards for certain PFAS chemical subtypes. The rule establishes legally enforceable levels, called Maximum Contaminant Levels (MCLs), for six types of PFAS in drinking water systems. For two other specific PFAS chemicals, EPA set Maximum Contaminant Level Goals (MCLGs), non-enforceable, health-based, public drinking water objectives, at zero.