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Adams County Regional Water District

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

Serves
21,810 people
Connections
7,311
Water source
Groundwater
Based in
West Union, OH
County
Adams
Owner
Local government
The 15 ZIP codes it serves

45101, 45105, 45115, 45144, 45167, 45168, 45616, 45618, 45650, 45657, 45660, 45679, 45684, 45693, 45697

The short answer

1 result is above the health goal. The worst: Lead, above the health goal. No health-based violations on file since 2016.

What handles it

What was found

PFAS and lithium: EPA UCMR 5, samples taken from Aug. 8, 2024 to Feb. 6, 2025.

Lead and copper: EPA SDWIS monitoring periods ending 2018 to 2025. Copper at 688 mg/L (2005) is left out of this report: it is one of the results Ohio sent EPA in 2006, all at µg/L magnitudes though EPA’s file marks them mg/L.

Total trihalomethanes (TTHM), fluoride, haloacetic acids (HAA5), nitrate, arsenic and chromium (total): Ohio’s own results, samples taken from Feb. 12, 2020 to July 8, 2025, with EPA’s 2012 to 2019 file for earlier years.

PFAS: None of the six PFAS in EPA’s 2024 drinking water rule was found in this utility’s samples. None of the other 23 PFAS tested for was found either.

EPA’s 2024 PFAS rule, compound by compound

PFASEPA’s limitResult
PFOA4.0 pptNot foundNot found in any of 2 samples, below 4 ppt
PFOS4.0 pptNot foundNot found in any of 2 samples, below 4 ppt
PFHxS10 pptNot foundNot found in any of 2 samples, below 3 ppt
PFNA10 pptNot foundNot found in any of 2 samples, below 4 ppt
HFPO-DA (GenX)10 pptNot foundNot found in any of 2 samples, below 5 ppt
PFBSIndex onlyNot foundNot found in any of 2 samples, below 3 ppt
Hazard IndexPFHxS, PFNA, HFPO-DA and PFBS together1Doesn’t applyDoesn’t apply: no sampling location found two or more of the four
Results from EPA’s UCMR 5 sampling. “Below” is the lab’s reporting level: a result under it reads as not found, which is not the same as zero. The limits are EPA’s 2024 rule, with compliance due from 2029; EPA has since proposed changes to some of them, explained on each compound’s page. PFBS has no limit of its own and counts only toward the Hazard Index, which adds up the four, each against EPA’s health-based level, from each sampling location’s average, as EPA’s UCMR 5 summary does. It counts only where two or more of the four were found, and is above the limit from 1.5.

Above the health goal1

Lead

Comes from pipes, often your own

Above the health goal

1.8ppb

90th percentile, 2025

In the latest period, 9 in 10 homes sampled were at or below 1.8 ppb, below EPA’s action level of 15 ppb. The action level drops to 10 ppb on Nov. 1, 2027. EPA’s health goal for lead is zero.

What handles it

Below EPA’s limits4

Total trihalomethanes (TTHM)

Forms or is added in treatment

Below EPA’s limits

34.3ppb

Highest yearly average, 2020 to 2025

2025 average: 27.9 ppb

Averaged by year, the highest was 34.3 ppb, in 2023, below EPA’s legal limit of 80 ppb. Its highest single sample was 50.9 ppb. In 2025, the latest year on file, its two samples averaged 27.9 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 31.8 ppb, in 2016.

What handles it

  • NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
  • NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”

Fluoride

Forms or is added in treatment

Below EPA’s limits

0.89ppm

Highest yearly average, 2020 to 2023

2023, one sample: 0.83 ppm

Averaged by year, the highest was 0.89 ppm, in 2020, below EPA’s legal limit of 4.0 ppm. In 2023, the latest year on file, its one sample was 0.83 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 0.97 ppm, in 2014.

What handles it

Haloacetic acids (HAA5)

Forms or is added in treatment

Below EPA’s limits

9.8ppb

Highest yearly average, 2020 to 2025

2025 average: 3.8 ppb

Averaged by year, the highest was 9.8 ppb, in 2024, below EPA’s legal limit of 60 ppb. Its highest single sample was 13.7 ppb. In 2025, the latest year on file, its two samples averaged 3.8 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 7.7 ppb, in 2016.

What handles it

No certification claim covers this compound yet.

Nitrate

Comes from the source

Below EPA’s limits

0.74ppm

Highest sample; found in 6 of 6

2025, one sample: 0.22 ppm

The highest sample, in 2020, was 0.74 ppm, below EPA’s legal limit of 10 ppm. In 2025, the latest year on file, its one sample was 0.22 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 0.29 ppm, in 2014.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
Ohio utilities above EPA’s PFAS limits
32 compounds tested and not foundIncluding all six PFAS in EPA’s 2024 rule. Below the reporting level in every sample. Not found is not the same as zero.

From routine monitoring

  • Arsenic
  • Chromium (total)

PFAS and lithium, from EPA’s UCMR 5 sampling

  • 11Cl-PF3OUdS
  • 4:2 FTS
  • 6:2 FTS
  • 8:2 FTS
  • 9Cl-PF3ONS
  • ADONA
  • HFPO-DA (GenX)
  • Lithium
  • NEtFOSAA
  • NFDHA
  • NMeFOSAA
  • PFBA
  • PFBS
  • PFDA
  • PFDoA
  • PFEESA
  • PFHpA
  • PFHpS
  • PFHxA
  • PFHxS
  • PFMBA
  • PFMPA
  • PFNA
  • PFOA
  • PFOS
  • PFPeA
  • PFPeS
  • PFTA
  • PFTrDA
  • PFUnA

What handles it

A certification covers specific claims, not a whole standard. Look for these claims on the certifier’s listing, not the box. Wording varies a little: NSF writes “Lead Reduction,” WQA just “Lead.”

At the tap, or for the whole house?

Lead and copper usually come from pipes and fixtures inside or near your home. A whole-house system sits where water enters, so it cannot catch what your own plumbing adds after it. For those, the filter that counts is the one at the tap. How whole-house systems compare.

Filters with those claims on a certifier’s listing

Disclosure: TapBuff earns a commission if you buy through some links on this page. It does not change which standard or filter we name. As an Amazon Associate, TapBuff earns from qualifying purchases. How TapBuff makes money

Compare five-year costs

The best water filters for lead, ranked

Disinfectant

Adams County Regional Water District reported disinfecting with chlorine, not chloramine, at its one sampling point, in its 2024 to 2025 sampling for EPA.

Chlorine leaves water that sits out for a few days, CDC says. A filter certified for it carries a chlorine claim under NSF/ANSI 42; a shower filter, a free chlorine claim under NSF/ANSI 177. This is what the utility reported for that sampling. Its annual water quality report says what it uses now.

Chlorine vs. chloramineShower filters, by what their listings cover

Violations since 2016

No health-based violations on file with EPA since 2016. There is 1 monitoring or reporting violation: a sample missed, late or not reported.

What this report can’t tell you

  • Everything else. Total trihalomethanes (TTHM), fluoride, haloacetic acids (HAA5), nitrate, arsenic and chromium (total) results here are Ohio’s own from 2020 on, with EPA’s national file for 2012 to 2019. Adams County Regional Water District’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 samples are from Aug. 8, 2024 to Feb. 6, 2025; Ohio’s results run from Feb. 12, 2020 to July 8, 2025.

Testing your own tap

Adams County Regional Water District’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 Ohio certifies.

The 3 labs Ohio certifies closest to the area Adams County Regional Water District serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • ALS Environmental - Cincinnati

    Cincinnati, OH · about 53 miles

    Certified for lead and copper, metals, asbestos

    (513) 733-5336

  • Q Laboratories

    Cincinnati, OH · about 58 miles

    Certified for bacteria, nitrate

    (513) 471-1300

  • Greene County Sanitary Engineering Laboratory

    Beavercreek, OH · about 68 miles

    Certified for bacteria, nitrate, minerals and other inorganics

    (937) 562-7450

All 76 certified labs for Ohio

Sources

PWSID OH0100012. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Adams County

All Ohio utilities

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