Darke County Water Quality

Name: Darke County Water Quality Data (2026)
Creator: PurityMap
License: https://creativecommons.org/licenses/by/4.0/

Darke County, Ohio: one city report built from EPA and utility records. A county has many suppliers; each city shows the system that serves it.

Find my system Open on the map Private wells in Darke County

Across the county's systems

Highest result for each contaminant

One row per contaminant: the highest result any system in the county reported, against its limit. Open a row for the systems behind it.

Perfluorooctanesulfonic acid (PFOS)GREENVILLE CITY PWS4.0 ng/L federal MCL (2024) · US EPA6.3 ng/L

GREENVILLE CITY PWS6.3 ng/LSample date: 2025-03-17 to 2025-09-03

Perfluorohexanesulfonic acid (PFHxS)GREENVILLE CITY PWS10 ng/L federal MCL (2024) · US EPA5.9 ng/L

GREENVILLE CITY PWS5.9 ng/LSample date: 2025-03-17 to 2025-09-03

29 substances tested, none detected in this systemShow

Tested in this system: GREENVILLE CITY PWS

11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)
1H, 1H, 2H, 2H-perfluorodecane sulfonic acid (8:2 FTS)
1H, 1H, 2H, 2H-perfluorohexane sulfonic acid (4:2 FTS)
1H, 1H, 2H, 2H-perfluorooctane sulfonic acid (6:2 FTS)
4,8-Dioxa-3H-perfluorononanoic acid (ADONA)
9-Chlorohexadecafluoro-3-oxanone-1-sulfonic acid (9Cl-PF3ONS)
Hexafluoropropylene oxide dimer acid (HFPO-DA) (GenX chemicals)
Lead (90th percentile)
Lithium
N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA)
N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA)
Nonafluoro-3,6-dioxaheptanoic acid (NFDHA)
Perfluoro (2-ethoxyethane) sulfonic acid (PFEESA)
Perfluoro-3-methoxypropanoic acid (PFMPA)
Perfluoro-4-methoxybutanoic acid (PFMBA)
Perfluorobutanesulfonic acid (PFBS)
Perfluorobutanoic acid (PFBA)
Perfluorodecanoic acid (PFDA)
Perfluorododecanoic acid (PFDoA)
Perfluoroheptanesulfonic acid (PFHpS)
Perfluoroheptanoic acid (PFHpA)
Perfluorohexanoic acid (PFHxA)
Perfluorononanoic acid (PFNA)
Perfluorooctanoic acid (PFOA)
Perfluoropentanesulfonic acid (PFPeS)
Perfluoropentanoic acid (PFPeA)
Perfluorotetradecanoic acid (PFTA)
Perfluorotridecanoic acid (PFTrDA)
Perfluoroundecanoic acid (PFUnA)

1 city

Cities ranked by the records

1
GreenvilleGREENVILLE CITY PWS
PFAS sample above a limit
Open city report →

Showing 1 of 1 cities · scores are system-level, not tap tests

Ranked by the Purity Score of each city's main water system, highest first. Scores belong to water systems; there is no county score. The score is computed only from contaminants measured in the published EPA record, so this ranks the record, not which city's water is safest. How the score works.

PFAS in Darke County1 of 1 city report had a PFAS sample above a 2024 EPA limit

Greenville6.3 ng/L

4.0 ng/L federal MCL · PFOS, ng/LPFAS in Ohio

Lead

0of 1 city above the 15 µg/L action level

Based on each system's 90th-percentile result. Lead from household plumbing isn't in this record.

Lead in Ohio

Who supplies the county

Largest water systems

GreenvilleGREENVILLE CITY PWS · OH1900714
13,227 served

Questions

Frequently asked

How does Darke County tap water compare across cities?

PurityMap ranks 1 city in Darke County by the Purity Score of each city's main water system, computed only from contaminants measured in the published EPA record. Scores belong to water systems, not to cities. The highest published score is Greenville's main water system: GREENVILLE CITY PWS · PWSID OH1900714 · Purity Score 65 (Fair) · Confidence: moderate · Assessed at the water-system level. The ranking compares the records, not which city's water is safest, and your own tap can differ with household plumbing.

How many Darke County cities had a PFAS sample above a 2024 EPA limit?

1 of 1 Darke County city report had a PFAS sample above a 2024 EPA limit in EPA's UCMR 5 testing, including Greenville (PFOS 6.3 ng/L). That limit is judged on a yearly average, and water systems have until 2029 to meet it, so a single sample is not a violation. PFAS were detected at any level in 1.

Is there lead in Darke County tap water?

Utilities report lead as a 90th-percentile result from home taps. 0 of 1 Darke County cities reported a value above zero, and none was above the 15 µg/L federal action level. Lead usually comes from a building's own pipes and fixtures, so only a test at your tap tells you what you drink.

Next step

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