Washington Guide
PFAS Contamination in Washington — What You Need to Know
Washington has some of the most significant PFAS contamination in the country. Here is where it has been found, what the state is doing about it, and how to protect your drinking water right now.
Last updated: April 2026 · By the PFASFilterGuide team
Washington PFAS Standard
4 ppt PFOA / 4 ppt PFOS (EPA MCL) — Washington Ecology adopted federal limits
Washington Department of Ecology adopted the federal EPA MCLs finalized in April 2024: 4 ppt for PFOA and PFOS individually. Washington has been proactive on PFAS — the state passed laws requiring PFAS disclosure in products, restricting PFAS in food packaging, and banning AFFF firefighting foam for training purposes. Ecology also monitors PFAS in Puget Sound fish tissue. As of 2026, Washington public water systems are working toward compliance with the federal MCL rollout timeline.
Known Contamination Sites
These are publicly documented PFAS detections in Washington. This is not a complete list — new sites are found regularly as testing expands.
| Location | Source | PFAS Level |
|---|---|---|
| Lakewood / DuPont (Pierce County) | Joint Base Lewis-McChord (JBLM) — multiple documented AFFF release sites from fire training and emergency operations | PFAS in groundwater monitoring wells throughout the large installation; Nisqually River watershed monitoring active; off-base residential wells in surrounding communities tested |
| Tacoma / McChord Field (Pierce County) | Historical firefighting operations at McChord Field — PFAS in surrounding residential groundwater | PFAS detected in monitoring wells affecting residential areas adjacent to the installation; treatment connections offered to some affected homes |
| Oak Harbor (Island County) | Naval Air Station Whidbey Island — AFFF from flight operations and training | PFAS detected in groundwater; Oak Harbor's water supply has been monitored; DoD investigation ongoing |
| Yakima Valley (Yakima County) | Agricultural biosolids application — PFAS uptake from biosolid-amended fields into irrigation water and groundwater | PFAS detected in agricultural wells and irrigation water; Washington Ecology has tested farm wells in biosolid-application areas |
| Richland / Hanford Site (Benton County) | Hanford Nuclear Reservation — decontamination foam containing PFAS used at the nuclear cleanup site | PFAS detected in groundwater at this complex contamination site; Columbia River monitoring ongoing |
| Everett / Paine Field (Snohomish County) | Paine Field Airport — AFFF use in aircraft firefighting training | PFAS detected in Snohomish County groundwater; monitoring under EPA UCMR5; some nearby private wells tested |
Military Base Contamination
AFFF firefighting foam used on military bases is one of the largest sources of PFAS groundwater contamination. The Department of Defense has identified these Washington bases:
Joint Base Lewis-McChord (Pierce County)
One of the largest military installations in the western US and one of the most significant PFAS contamination sites in Washington State. Multiple documented AFFF release sites from decades of fire training. DoD Environmental Restoration Program is active with ongoing groundwater monitoring. Some residential areas adjacent to the installation have been offered alternative water connections. Nisqually River watershed monitoring is ongoing.
Naval Air Station Whidbey Island (Oak Harbor, Island County)
AFFF contamination from flight operations and fire training. Groundwater monitoring ongoing. Oak Harbor municipal water supply has been tested and is being monitored. Private well owners on Whidbey Island near the base should contact Island County Health for testing guidance.
Washington PFAS Regulations
- Washington Ecology adopted federal EPA MCLs: 4 ppt PFOA, 4 ppt PFOS, 10 ppt for PFHxS, PFNA, and HFPO-DA
- Washington banned PFAS in food packaging and certain consumer products — ahead of federal action
- Washington restricted AFFF use to emergency response only; training use prohibited
- Washington Ecology monitors PFAS in Puget Sound seafood and fish tissue
- Washington Ecology conducts biosolids PFAS monitoring and has tested agricultural wells in affected areas
- Washington public water systems tested under UCMR5 with results published in Consumer Confidence Reports
How to Test Your Water in Washington
Washington Department of Ecology oversees PFAS monitoring statewide, including public water system testing under EPA UCMR5. Washington has also conducted additional voluntary testing — particularly in agricultural areas where biosolids have been applied and in Puget Sound fish tissue monitoring. If you are on a private well near JBLM in Pierce County, Whidbey Island in Island County, or Paine Field in Snohomish County, contact your county health department about available testing. Washington Ecology has funded well testing in some affected agricultural areas. Mail-in PFAS testing from Tap Score or SimpleLab ($150-$300) is available to any Washington resident and covers your actual tap water, not just the utility report.
Recommended Filters for Washington Residents
Any NSF P473 certified filter removes PFAS. The right type depends on whether you rent or own, and how many taps you want filtered.
Renters / Budget
Clearly Filtered Pitcher — $80 + $60/yr filters. NSF P473. No install.
See full reviewHomeowners / Kitchen
Under-sink RO system — $200-$400. Filters all drinking + cooking water at one tap.
See full reviewWhole-House
SpringWell PFAS system — $1,500+. Filters every tap including showers and laundry.
See full reviewCommon Questions
Does Washington State have PFAS in tap water?+
Some areas do. The highest risk is near Joint Base Lewis-McChord in Pierce County and Whidbey Island in Island County. Agricultural areas in the Yakima Valley where biosolids have been applied also have documented well contamination. Seattle and major urban water utilities in Washington have tested under UCMR5 and publish results in Consumer Confidence Reports — most large urban systems are meeting current standards, but ongoing monitoring is required. Private well owners near military bases or biosolid application areas face the highest uncertainty.
Is Puget Sound seafood safe from PFAS?+
Washington Ecology has found PFAS in Puget Sound fish tissue, particularly in bottom-feeding fish and shellfish. The levels vary by location and species. Washington has not issued a blanket advisory to stop eating Puget Sound seafood, but Ecology recommends checking the most current fish advisories on its website. Recreationally caught bottom fish from areas near industrial or military discharge points carry higher risk. Commercially caught seafood from open ocean sources is generally lower risk than locally caught Puget Sound species.
What is Washington doing about PFAS?+
Washington has been one of the more active states on PFAS policy. The state has banned PFAS in food packaging, restricted AFFF to emergency use only, monitored PFAS in Puget Sound and agricultural areas, and adopted federal EPA MCLs for drinking water. Washington Ecology has also tested biosolids and farm wells in areas where PFAS-contaminated sludge may have been applied. The state has pushed for stronger federal standards and participated in multistate legal efforts.
Are there PFAS in Washington fish?+
Yes. Washington Ecology has found PFAS in fish tissue in Puget Sound and in some freshwater bodies. The compounds accumulate in fatty tissue and are higher in predatory fish species. Washington publishes fish consumption advisories that are updated periodically. For the most current guidance on specific water bodies, check the Washington Department of Health fish advisory page. Areas near military bases and industrial sites carry higher risk.
What filter removes PFAS from Seattle or Washington tap water?+
NSF P473 certified filters remove PFAS from tap water regardless of your water source. Clearly Filtered pitcher and Aquasana under-sink systems carry this certification. For more complete removal — including emerging PFAS compounds — a reverse osmosis under-sink system removes 99%+ of PFAS. If you are in Seattle or another large city with treated public water, a pitcher or under-sink filter adds a meaningful safety margin above what the utility provides. If you are on a private well near JBLM or Whidbey Island, an under-sink RO system is the stronger choice.
Protect Your Water Now
You do not need to wait for your state to act. An NSF P473 certified filter removes PFAS from your tap water today. Start with a test to know your levels, then pick the filter that fits your home.