Summary
Chapter 246-290 WAC sets rules for large public water systems. These rules ensure public water systems are safe and reliable to protect public health. In 2024, the Environmental Protection Agency adopted new standards that affect the rule. The Board adopted amendments to align with the federal standard and keep drinking water safe.
For More Information
Statutory Authority: RCW 43.20.050, RCW 70A.125, and RCW 70A.130
State Board of Health Contact: Shay Bauman, shay.bauman@sboh.wa.gov
Department of Health Contacts: Zehra Siddiqui, zehra.siddiqui@doh.wa.gov, and Mike Means, mike.means@doh.wa.gov
Additional Background
The State Board of Health (Board) adopted proposed changes to WAC 246-290-315 and WAC 246-290-71006 on December 15, 2025. The adopted changes keep current protections related to per- and polyfluoroalkyl substances (PFAS) in place until new federal regulations are effective.
On April 10, 2024, the U.S. Environmental Protection Agency (EPA) published the first national standards related to per- and polyfluoroalkyl substances (PFAS) in drinking water. The EPA officially adopted the standards on June 24, 2024. The federal standards affect the Board’s Group A Public Water Supplies rule, chapter 246-290 WAC.
The Board adopted state action levels and other requirements for PFAS in drinking water in 2021. These rules include criteria that would apply when the EPA adopts a federal maximum contaminant level (MCL) that has a state action level (SAL) set in rule. This provision states that when the EPA adopts MCLs, those MCLs and their requirements, including for monitoring and public notice, replace what rule establishes for SALs.
The EPA adopted the rule on June 24, 2024, but the MCLs do not take effect until April 2029. This would mean that the current protections provided under the SALs would go away until 2029. This includes the requirement that water companies notify customers of dangerous detections of PFAS within 30-days of the detection. To prevent this and preserve public health, the Board adopted an emergency amendment to the rule. This amendment clarifies that the MCLs and associated requirements would replace the SALs when the MCLs are effective, instead of when they are adopted. Emergency rules stay in effect for 120 days. The Board filed a fifth emergency rule on October 16, 2025. The Board will consider additional emergency filings to keep this amendment until it is permanently adopted.
The updated Board rules will:
- Align the SALs for PFAS with newly adopted federal MCLs to provide optimal protection from PFAS in the state’s drinking water.
- Maintain state required testing for PFAS in Group A public water systems.
- Clarify reporting requirements and ease confusion about which set of health-based standards apply until the federal regulation becomes effective in April 2029.
These changes aim to align the rule with the best available science related to PFAS contaminant levels and provide advanced public health protection. The changes also help ensure the rules are clear and effective. The updated rules will go into effect January 16, 2026.
The Board filed a CR-101 as WSR 24-20-093 on September 30, 2024, to consider changes to WAC 246-290-315 and WAC 246-290-71006. The Board adopted changes to keep current protections related to per- and polyfluoroalkyl substances (PFAS) in place until new federal regulations are effective and permanently adopted the amendments made in the emergency rulemaking. The Board also adopted new SALs for PFAS based on the Environmental Protection Agency’s (EPA) new science, in addition to other changes. The Board will conduct an environmental justice assessment, small business economic impact statement, and a significant analysis to review the potential changes. These analyses will inform their decision-making.
Rulemaking Timeline
- Informal comment period: May 29 – June 11
- File CR-102 – September 2025
- Formal comment period – October 2025
- Public hearing – November 2025
- File CR-103 – December 15, 2025
- Rule Effective January 15, 2026
Emergency Rulemaking
CR-103E
CR-103E - Second Filing
CR-103E - Third Filing
CR-103E - Fourth Filing
CR-103E - Fifth Filing
Adopted Rule (English)
Adopted Rule (Spanish)
Exception Rulemaking
Permanent Rulemaking
CR-101
CR-102
CR-103P: Rulemaking Order with Permanent Rule Language
Concise Explanatory Statement
Significant Analysis
Environmental Justice Assessment
Related Links
November 19, 2025, Board Meeting – Public Hearing
- PFAS Cover Memo
- Board Staff Presentation
- Department of Health Presentation
- Meeting Minutes - Available by 1/7/2026
