What was found in Louisville'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 |
|---|---|---|---|
| Fluoride | 745.6 µg/L 19% of the EPA limit 4000 µg/L Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 2083.25 µg/L — LOUISVILLE CENTER FOR REHABILITATION · 172 people · 2019 | 4/5 | SYR4 |
| Copper | 192.1 µg/L 15% of the EPA limit 1300 µg/L Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2017
Highest in the city: 350 µg/L — EAST CANTON VILLAGE PWS · 1,606 people · 2019 | 5/5 | SYR4 |
| Nitrate | 270 µg/L 2.7% of the EPA limit 10000 µg/L Highest in the city: LOUISVILLE GARDENS HEALTH CENTER · 81 people · 2019 | 1/5 | SYR4 |
| Nitrate-Nitrite | 270 µg/L 2.7% of the EPA limit 10000 µg/L Highest in the city: LOUISVILLE GARDENS HEALTH CENTER · 81 people · 2014 | 1/5 | SYR4 |
| Barium | 134.8 µg/L 6.7% of the EPA limit 2000 µg/L Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019 | 4/5 | SYR4 |
| TTHM | 87.86 µg/L 110% of the EPA limit, at the 95th percentile of samples — 80 µg/L Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 132.885 µg/L — GREEN MEADOWS HEALTH AND WELLNESS CENTER · 182 people · 2019 | 5/5 | SYR4 |
| Total Haloacetic Acids (HAA5) | 23.65 µg/L 39% of the EPA limit 60 µg/L Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 83.815 µg/L — GREEN MEADOWS HEALTH AND WELLNESS CENTER · 182 people · 2019 | 5/5 | SYR4 |
| Bromodichloromethane | 11.75 µg/L No EPA limit set Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 56.5 µg/L — GREEN MEADOWS HEALTH AND WELLNESS CENTER · 182 people · 2019 | 5/5 | SYR4 |
| Chloroform | 52.7 µg/L No EPA limit set Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019 | 5/5 | SYR4 |
| Dichloroacetic Acid | 8.886 µg/L No EPA limit set Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 50.845 µg/L — GREEN MEADOWS HEALTH AND WELLNESS CENTER · 182 people · 2019 | 5/5 | SYR4 |
| Dibromochloromethane | 10.55 µg/L No EPA limit set Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 34.75 µg/L — GREEN MEADOWS HEALTH AND WELLNESS CENTER · 182 people · 2019 | 5/5 | SYR4 |
| Trichloroacetic Acid | 5.21 µg/L No EPA limit set Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 26.195 µg/L — LOUISVILLE CENTER FOR REHABILITATION · 172 people · 2019 | 5/5 | SYR4 |
| Chromium | 1 µg/L 1% of the EPA limit 100 µg/L Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 24.7735 µg/L — LOUISVILLE CENTER FOR REHABILITATION · 172 people · 2019 | 3/5 | SYR4 |
| Monochloroacetic Acid | 2.856 µg/L No EPA limit set Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 21.2 µg/L — GREEN MEADOWS HEALTH AND WELLNESS CENTER · 182 people · 2019 | 4/5 | SYR4 |
| Lead | 5.3 µg/L 35% of the EPA limit 15 µg/L Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2017
Highest in the city: 18.225 µg/L — EAST CANTON VILLAGE PWS · 1,606 people · 2019 | 4/5 | SYR4 |
| Bromoform | 3.422 µg/L No EPA limit set Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 14.9 µg/L — LOUISVILLE GARDENS HEALTH CENTER · 81 people · 2019 | 5/5 | SYR4 |
| Dibromoacetic Acid | 4.2295 µg/L No EPA limit set Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019
Highest in the city: 14.57 µg/L — GREEN MEADOWS HEALTH AND WELLNESS CENTER · 182 people · 2019 | 5/5 | SYR4 |
| Lithium | 9 µg/L No EPA limit set Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2024 | 1/5 | UCMR-5 |
| Monobromoacetic Acid | 2.5 µg/L No EPA limit set Highest in the city: EAST CANTON VILLAGE PWS · 1,606 people · 2019 | 3/5 | SYR4 |
| Selenium | 1.52 µg/L 3% of the EPA limit 50 µg/L Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019 | 3/5 | SYR4 |
| P-Dichlorobenzene | 0.7000 µg/L 0.9% of the EPA limit 75 µg/L Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2019 | 1/5 | SYR4 |
| Pfpea | 0.0030 µg/L No EPA limit set Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2024 | 1/5 | UCMR-5 |
| Lead | 0.0012 mg/L 8.3% of the EPA limit 0.0150 mg/L Main supplier: LOUISVILLE CITY PWS · 9,186 people · 2023 | 5/5 | LCR |
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 Louisville
| Supplier | Population served |
|---|---|
| LOUISVILLE CITY PWS | 9,186 |
| EAST CANTON VILLAGE PWS | 1,606 |
| GREEN MEADOWS HEALTH AND WELLNESS CENTER | 182 |
| LOUISVILLE CENTER FOR REHABILITATION | 172 |
| LOUISVILLE GARDENS HEALTH CENTER | 81 |
Frequently asked questions about Louisville tap water
Is Louisville tap water safe to drink?
EPA testing detected 23 contaminants in the water serving Louisville. 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 Louisville?
5 public water suppliers report drinking-water monitoring for Louisville, Ohio to the EPA. Each is listed above with its population served.
What contaminants are in Louisville's water?
The contaminants EPA monitoring detected in Louisville include Fluoride, Copper, Nitrate, Nitrate-Nitrite, Barium. 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.