Regulation ChangeLiveLive Regulation
Washington updates PFAS drinking water regulations effective January 15, 2026
WAC 246-290-315 and WAC 246-290-71006Washington State Board of Health / Washington State Department of HealthWashington
Announced
Dec 15, 2025
Effective
Jan 15, 2026
Implementation
Jan 15, 2026
Description
The Washington State Board of Health adopted changes to WAC 246-290-315 and WAC 246-290-71006 on December 15, 2025. The updated rules maintain current protections related to PFAS in drinking water until new federal regulations are effective, and align State Action Levels (SALs) with federal Maximum Contaminant Levels (MCLs). The rules are effective January 15, 2026, and establish monitoring requirements transitioning from confirmed detection to running annual average (RAA) methodology.
Key Findings
Washington updates PFAS drinking water regulations effective January 15, 2026
 [About Us](/about-us) | [Contact Us](/about-us/contact-us) | [Newsroom](/newsroom) breadcrumb # PFAS in Drinking Water—Group A Public Water System Information and Support The State Board of Health (Board) revised the [WAC 246-290 Group A Drinking Water Rules](https://app.leg.wa.gov/wac/default.aspx?cite=246-