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Is there PFAS in Lakehaven Water and Sewer District water?

Some. At least one sample reached an EPA limit, but the average at every sampling point stayed below it.

Lakehaven Water and Sewer District Serves 148,809 people · 34 PFOA samples from 16 sampling points · Jul 2024 to Mar 2025 One or more samples at an EPA limit
PFOA Perfluorooctanoic acid not detected
EPA 4
PFOS Perfluorooctanesulfonic acid 2.1 ppt avg · max 4.1
EPA 4
PFHxS Perfluorohexanesulfonic acid 5.8 ppt avg
EPA 10
Hazard index GenX, PFBS, PFNA, PFHxS combined 0.6 avg
EPA 1

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

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

Lakehaven Water and Sewer District is a public water system drawing on surface water, based in Federal Way, Washington, serving about 148,809 people, including Auburn, Federal Way. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 34 times across 16 sampling points between Jul 2024 and Mar 2025.

Every PFAS detected

PFAS Detected Highest Worst point avg EPA limit
PFPeA
Perfluoropentanoic acid
2 of 34 13.7 ppt 12.7 ppt none
PFHxA
Perfluorohexanoic acid
2 of 34 7.6 ppt 7.5 ppt none
PFHxS
Perfluorohexanesulfonic acid
2 of 34 5.8 ppt 5.8 ppt 10 ppt
PFOS
Perfluorooctanesulfonic acid
2 of 34 4.1 ppt 2.1 ppt 4 ppt
PFBS
Perfluorobutanesulfonic acid
1 of 34 4.0 ppt 2.0 ppt none
PFHpA
Perfluoroheptanoic acid
2 of 34 3.6 ppt 3.5 ppt none

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

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

98001 98003 98023 98063

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 Lakehaven Water and Sewer District water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID WA5341997. https://wellandtap.com/pfas/washington/lakehaven-water-and-sewer-district/

About this data

Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID WA5341997). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.