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Is there PFAS in Covington Water District water?

Yes. EPA's final UCMR 5 results show Covington Water District averaged 8.4 ppt of PFOS at its worst sampling point, 2.1 times the EPA limit of 4 ppt.

Covington Water District Serves 56,172 people · 8 PFOA samples from 3 sampling points · Jan 2024 to Nov 2024 Average above an EPA limit
PFOA Perfluorooctanoic acid not detected
EPA 4
PFOS Perfluorooctanesulfonic acid 8.4 ppt avg · max 8.6
EPA 4
PFHxS Perfluorohexanesulfonic acid 7.0 ppt avg · max 7.5
EPA 10
Hazard index GenX, PFBS, PFNA, PFHxS combined 0.7 avg · max 0.8
EPA 1

Also detected, no federal limit: PFBS, PFPeA, PFHxA.

Averages are for the worst sampling point, with non-detects counted as zero. Source: EPA UCMR 5.

Covington Water District is a public water system drawing on surface water, based in Kent, Washington, serving about 56,172 people, including Black Diamond, Maple Valley, Kent, Ravensdale, Auburn. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 8 times across 3 sampling points between Jan 2024 and Nov 2024.

Every PFAS detected

PFAS Detected Highest Worst point avg EPA limit
PFBS
Perfluorobutanesulfonic acid
2 of 8 14.0 ppt 13.5 ppt none
PFOS
Perfluorooctanesulfonic acid
2 of 8 8.6 ppt 8.4 ppt 4 ppt
PFHxS
Perfluorohexanesulfonic acid
2 of 8 7.5 ppt 7.0 ppt 10 ppt
PFPeA
Perfluoropentanoic acid
2 of 8 3.9 ppt 3.6 ppt none
PFHxA
Perfluorohexanoic acid
1 of 8 3.3 ppt 1.6 ppt none

Not detected: PFHpS, PFPeS, PFTA, PFEESA, PFMBA, NFDHA, PFTrDA, NEtFOSAA, NMeFOSAA, PFDA, PFNA, 9Cl-PF3ONS, PFOA, PFDoA, PFHpA, 11Cl-PF3OUdS, PFMPA, ADONA, HFPO-DA, PFBA, 6:2 FTS, 4:2 FTS, 8:2 FTS, PFUnA.

Lithium, tested in the same program: not detected.

What the EPA limits mean here

In April 2024 EPA set enforceable limits of 4 ppt for PFOA and PFOS, 10 ppt each for PFHxS, PFNA and GenX, and a hazard index of 1 for mixtures. Utilities were given until 2029 to comply. In May 2026 EPA proposed keeping only the PFOA and PFOS limits and moving that deadline to 2031. Until that proposal is final, the 2024 limits stand.

Compliance is judged on a running annual average at each entry point, so we show the average at this system's worst sampling point next to its single highest result. UCMR 5 results do not by themselves put a utility in or out of compliance.

What you can do at home

Two routes work for PFAS. For drinking and cooking water only, a reverse osmosis system certified to NSF/ANSI 58 with a PFOA/PFOS reduction claim is the cheapest proven option. To treat every tap and shower, a whole-house carbon system with enough contact time works, but check that the maker has PFAS test data, not just a marketing claim. See the best filters for PFAS and how PFAS removal works.

Other systems in Washington

All 248 tested systems in Washington

ZIP codes served

98010 98038 98042 98051 98092

As reported by the utility to EPA. Neighbouring ZIPs are often split between systems; your water bill names yours.

Cite this page

Well & Tap. "PFAS in Covington Water District water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID WA5341650. https://wellandtap.com/pfas/washington/covington-water-district/

About this data

Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID WA5341650). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.