What was found in Hamilton's water
The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 4050 µg/L 41% of the EPA limit 10000 µg/L Highest in the city: CROUSE MOBILE HOME PARK & SALES, LLC · 247 people · 2019 | 3/4 | SYR4 |
| Nitrate-Nitrite | 4035 µg/L 40% of the EPA limit 10000 µg/L Highest in the city: CROUSE MOBILE HOME PARK & SALES, LLC · 247 people · 2019 | 3/4 | SYR4 |
| Copper | 31.86 µg/L 2.5% of the EPA limit 1300 µg/L Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2017
Highest in the city: 1303 µg/L — SOUTHWEST REGIONAL WATER DISTRICT · 42,856 people · 2019 | 4/4 | SYR4 |
| Fluoride | 1026.8 µg/L 26% of the EPA limit 4000 µg/L Highest in the city: FAIRFIELD CITY PWS · 44,907 people · 2017 | 2/4 | SYR4 |
| Lead | 12.655 µg/L 84% of the EPA limit 15 µg/L Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2017
Highest in the city: 50.585 µg/L — FAIRFIELD CITY PWS · 44,907 people · 2019 | 4/4 | SYR4 |
| TTHM | 41.145 µg/L 51% of the EPA limit 80 µg/L Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2019 | 3/4 | SYR4 |
| Barium | 39.43 µg/L 2% of the EPA limit 2000 µg/L Highest in the city: SOUTHWEST REGIONAL WATER DISTRICT · 42,856 people · 2017 | 2/4 | SYR4 |
| Dibromochloromethane | 16.39 µg/L No EPA limit set Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2019 | 4/4 | SYR4 |
| Bromoform | 13.645 µg/L No EPA limit set Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2019 | 3/4 | SYR4 |
| Total Haloacetic Acids (HAA5) | 11.42 µg/L 19% of the EPA limit 60 µg/L Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2019 | 3/4 | SYR4 |
| Bromodichloromethane | 10.58 µg/L No EPA limit set Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2019
Highest in the city: 11.12 µg/L — FAIRFIELD CITY PWS · 44,907 people · 2019 | 3/4 | SYR4 |
| Chloroform | 9.384 µg/L No EPA limit set Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2019 | 3/4 | SYR4 |
| Dibromoacetic Acid | 7.0095 µg/L No EPA limit set Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2019 | 3/4 | SYR4 |
| Dichloroacetic Acid | 4.7903 µg/L No EPA limit set Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2019 | 3/4 | SYR4 |
| Monochloroacetic Acid | 4.2404 µg/L No EPA limit set Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2019 | 1/4 | SYR4 |
| Trichloroacetic Acid | 3.61 µg/L No EPA limit set Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2019 | 3/4 | SYR4 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2025
Highest in the city: 0.0058 mg/L — CROUSE MOBILE HOME PARK & SALES, LLC · 247 people · 2025 | 4/4 | LCR |
| Hfpo-Da | 0.0057 µg/L No EPA limit set Highest in the city: FAIRFIELD CITY PWS · 44,907 people · 2024 | 1/4 | UCMR-5 |
| Pfba | 0.0057 µg/L No EPA limit set Highest in the city: FAIRFIELD CITY PWS · 44,907 people · 2024 | 1/4 | UCMR-5 |
| PFHXS | 0.0047 µg/L No EPA limit set Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2025 | 1/4 | UCMR-5 |
| Pfpea | 0.0043 µg/L No EPA limit set Highest in the city: FAIRFIELD CITY PWS · 44,907 people · 2024 | 1/4 | UCMR-5 |
| PFBS | 0.0035 µg/L No EPA limit set Main supplier: BUTLER CO. WATER DISTRICT 2 PWS · 116,572 people · 2025 | 2/4 | UCMR-5 |
| Pfhxa | 0.0030 µg/L No EPA limit set Highest in the city: FAIRFIELD CITY PWS · 44,907 people · 2024 | 1/4 | UCMR-5 |
Each bar shows the measured level as a share of the EPA limit: green is
well under, amber is close to it, red is over. For lead and copper the
limit applies to exactly the 90th-percentile figure shown, so red there
means a real exceedance. For everything else the limit applies to a
running annual average while the figure is the 95th percentile of the
system's samples — over 100% is worth reading, but is not by itself a
violation.
Formal violations are listed separately.
These are the utilities' own EPA-reported results, not a city-wide
average. A detection means the lab measured the
substance — it isn't the same as exceeding a legal limit. Hover a source
tag to see the EPA program and years behind each figure.
Water suppliers serving Hamilton
| Supplier | Population served |
|---|---|
| BUTLER CO. WATER DISTRICT 2 PWS | 116,572 |
| FAIRFIELD CITY PWS | 44,907 |
| SOUTHWEST REGIONAL WATER DISTRICT | 42,856 |
| CROUSE MOBILE HOME PARK & SALES, LLC | 247 |
Frequently asked questions about Hamilton tap water
Is Hamilton tap water safe to drink?
EPA testing detected 23 contaminants in the water serving Hamilton. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.
How many water suppliers serve Hamilton?
4 public water suppliers report drinking-water monitoring for Hamilton, Ohio to the EPA. Each is listed above with its population served.
What contaminants are in Hamilton's water?
The contaminants EPA monitoring detected in Hamilton include Nitrate, Nitrate-Nitrite, Copper, Fluoride, Lead. The full list, with the level at the main supplier and the data source, is in the table above.
Where does this data come from?
Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.