Drinking water quality · 2024
· Verified
· PWSID KY0560258
What's in Louisville, KY tap water
1 contaminant in Louisville, KY's water sat at or above a federal limit, led by PFOA (Perfluorooctanoic acid) at 1.9x the limit.
- !1 contaminant at or above a federal limit — worst is PFOA (Perfluorooctanoic acid) at 1.9x
- !11 of 27 core regulated contaminants reported — 16 never appear in this report
- ✓No open federal violations
+How this score is calculated
Every system starts at 100. Points come off for measured levels, for the federal violation record, and for how much of the core regulated set the utility actually reported. All three inputs are the utility's own published numbers and EPA's own records.
- −23 contaminants at or above a federal limit
- −0 contaminants within 20% of a limit
- −0 open health-based violations
- −0 open monitoring / reporting violations
- −0 health-based violations resolved in the last 5 years
- −13 core regulated contaminants never reported (11/27)
A 90–100 · B 80–89 · C 70–79 · D 60–69 · F below 60. A system reporting under a third of the core set is capped at C however clean its numbers look — a short report is not a clean bill of health.
Full grading methodology, constant for constant →What to worry about
- PFOA (Perfluorooctanoic acid)1.9× the federal limit7.5 ng/L · limit 4 ng/L
Linked to cancer, liver damage, and immune effects; the EPA set an enforceable limit of 4 parts per trillion.
higher than 80% of U.S. systems
+22 contaminants were measured and came in below the limitShow all
| Contaminant | Measured | Federal limit |
|---|---|---|
| Chlorine | 2.71 mg/L | 4 mg/L |
| TTHM | 32.1 ug/L | 80 ug/L |
| HAA5 | 23.5 ug/L | 60 ug/L |
| Chlorite | 0.23 mg/L | 1 mg/L |
| Fluoride | 0.71 mg/L | 4 mg/L |
| Nitrate | 0.84 mg/L | 10 mg/L |
| Lead | 1.1 ug/L | 15 ug/L |
| Turbidity | 0.06 NTU | 1 NTU |
| Copper | 0.041 mg/L | 1.3 mg/L |
| Barium | 0.024 mg/L | 2 mg/L |
| Chromium, Total | 1.1 ug/L | 100 ug/L |
| Nitrite | 0.01 mg/L | 1 mg/L |
| Twofourd | 0.29 ug/L | 70 ug/L |
| Nickel | 0.0013 mg/L | — |
| Hexafluoropropylene oxide dimer acid | 0 ng/L | 10 ng/L |
| Perfluorohexanesulfonic acid | 0 ng/L | 10 ng/L |
| Perfluorononanoic acid | 0 ng/L | 10 ng/L |
| PFOS | 0 ng/L | 4 ng/L |
| TOC | 1.56 | — |
| PFPeA | 4.1000000000000005 ng/L | — |
| PFHxA | 3.6 ng/L | — |
| PFBS | 3 ng/L | — |
What this report doesn't tell you
16 of the 27 contaminants a community water system normally reports do not appear anywhere in Louisville, KY's data. Absent is not the same as absent-from-the-water — it means nobody published a number.
+Full detail: PFAS testing, water source, historical monitoring, and the federal violation record
PFAS — EPA UCMR5 (2023–2025)
1 PFAS compound above EPA limits in Louisville, KY
The EPA finalized the first-ever federal drinking-water limits for six PFAS compounds in April 2024. These numbers come straight from EPA's UCMR5 lab dataset — every U.S. system serving more than 3,300 people tested every PFAS sample at an entry point to its distribution system. PFAS not listed below were either tested and not detected, or not yet sampled.
PFOA (Perfluorooctanoic acid)
● Over EPA limit (1.9×)PFPeA
● Detected (no federal limit)PFHxA
● Detected (no federal limit)PFBS
● Detected (no federal limit)Where your water comes from · EPA SDWIS
Louisville, KY's drinking water comes from ground water, drawn from 7 sources.
Source
- BE PAYNE · 5
- INTAKE - OHIO RIVER TPA
- INTAKE - OHIO RIVER TPB
Treatment
- B E PAYNE WTP
- CRESCENT HILL WTP
Distribution
Compliance history
Federal Safe Drinking Water Act violation & enforcement records (EPA SDWIS). A violation is a regulatory determination by the state or EPA — separate from the measured levels above.
- Maximum contaminant level exceededHealth-based7 violations on record · most recent Jun 1998resolved
Source: EPA SDWIS / ECHO. View the full federal record on EPA ECHO ↗