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Lyon Co RWD 4

What EPA’s and Kansas’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves
980 people
Connections
395
Water source
Surface water bought from another system
Based in
Neosho Rapids, KS
County
Lyon
Owner
Local government
The 3 ZIP codes it serves

66801, 66864, 66868

The short answer

Nothing in EPA’s and Kansas’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. No health-based violations on file since 2016.

What was found

Haloacetic acids (HAA5) and total trihalomethanes (TTHM): Kansas’s own results, samples taken from July 28, 2020 to July 20, 2026, with EPA’s 2012 to 2019 file for earlier years.

Below EPA’s limits2

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

14ppb

Highest yearly average, 2020 to 2026

2026, one sample: 12 ppb

Averaged by year, the highest was 14 ppb, in 2021, below EPA’s legal limit of 60 ppb. In 2026, the latest year on file, its one sample was 12 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 12 ppb, in 2017.

What handles it

No certification claim covers this compound yet.

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

5.4ppb

Highest yearly average, 2020 to 2026

Averaged by year, the highest was 5.4 ppb, in 2026, below EPA’s legal limit of 80 ppb. That was also the latest year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 5.7 ppb, in 2016.

What handles it

  • NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
  • NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Lead

Violations since 2016

No health-based violations on file with EPA since 2016. There are 3 monitoring or reporting violations: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Haloacetic acids (HAA5) and total trihalomethanes (TTHM) results here are Kansas’s own from 2020 on, with EPA’s national file for 2012 to 2019. Lyon Co RWD 4’s own annual report, which it must send you every year, has the contaminants this page does not show.

  • Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.

  • What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.

  • Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; Kansas’s results run from July 28, 2020 to July 20, 2026.

Testing your own tap

Lyon Co RWD 4’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab Kansas certifies.

The 3 labs Kansas certifies closest to the area Lyon Co RWD 4 serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Irwin Army Community Hospital-Water Laboratory-PH-EH

    Fort Riley, KS · about 60 miles

    Certified for bacteria

    (785) 239-7516

  • Johnson County Water Quality Laboratory

    Olathe, KS · about 71 miles

    Certified for bacteria, nitrate, lead and copper

    (913) 715-6950

  • Olathe Environmental Laboratory

    Olathe, KS · about 71 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics

    (913) 971-8310

All 47 certified labs for Kansas

Sources

PWSID KS2011110. Rebuilt from EPA data on Oct. 18, 2026.

Also in Lyon County

All Kansas utilities

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