# Louisville, KY — Drinking Water Quality (2024)

> Contaminant levels for the Louisville, KY public water system from its 2024 Consumer Confidence Report, compared to federal limits.

- Page: https://www.thewatermap.com/water/ky/louisville/2024
- JSON API: https://www.thewatermap.com/api/water/ky/louisville/2024
- Source: the utility's annual Consumer Confidence Report (CCR)
- Verification: transcribed by a model, cross-checked by a second model, approved before publishing
- Reporting year: 2024
- Contaminants measured: 19
- Contaminants with a federal limit: 16
- Contaminants at or above the federal limit: 0
- Part of The Water Map — https://www.thewatermap.com

## Contaminants measured

| Contaminant | Category | Measured level | Sampling context | Federal limit | Status |
|---|---|---|---|---|---|
| Chlorine | Disinfectants | 2.71 mg/L (Average) | System-wide | 4 mg/L (MRDL) | Within the limit |
| Chlorite | Disinfection byproducts | 0.23 mg/L (Average) | System-wide | 1 mg/L (MCL) | Within the limit |
| HAA5 | Disinfection byproducts | 23.5 ug/L (Average) | System-wide | 60 ug/L (MCL) | Within the limit |
| TTHM | Disinfection byproducts | 32.1 ug/L (Average) | System-wide | 80 ug/L (MCL) | Within the limit |
| Fluoride | Inorganic chemicals | 0.71 mg/L (Average) | Bep | 4 mg/L (MCL) | Within the limit |
| Nitrate | Inorganic chemicals | 0.84 mg/L (Average) | Ch | 10 mg/L (MCL) | Within the limit |
| Nitrite | Inorganic chemicals | 0.01 mg/L (Maximum) | Ch | 1 mg/L (MCL) | Within the limit |
| Barium | Metals | 0.024 mg/L (Average) | Ch | 2 mg/L (MCL) | Within the limit |
| Chromium, Total | Metals | 1.1 ug/L (Average) | Bep | 100 ug/L (MCL) | Within the limit |
| Copper | Metals | 0.041 mg/L (90th percentile) | At the tap | 1.3 mg/L (MCLG) | Within the limit |
| Lead | Metals | 1.1 ug/L (90th percentile) | At the tap | 0 ug/L (MCLG) | Detected — no federal limit |
| Nickel | Metals | 0.0013 mg/L (Average) | Ch | No federal limit | Detected — no federal limit |
| Hexafluoropropylene oxide dimer acid | PFAS ("forever chemicals") | 0 (Reported level) | Crescent Hill Water Treatment Plant | 10 (MCL) | None detected |
| Perfluorohexanesulfonic acid | PFAS ("forever chemicals") | 0 (Reported level) | B.E. Payne Water Treatment Plant | 10 (MCL) | None detected |
| Perfluorononanoic acid | PFAS ("forever chemicals") | 0 (Reported level) | B.E. Payne Water Treatment Plant | 10 (MCL) | None detected |
| PFOA | PFAS ("forever chemicals") | 1.9 (Reported level) | Crescent Hill Water Treatment Plant | 4 (MCL) | Within the limit |
| PFOS | PFAS ("forever chemicals") | 0 (Reported level) | B.E. Payne Water Treatment Plant | 4 (MCL) | None detected |
| TOC | Physical & aggregate | 1.56 (Average) | Ch | No federal limit | Detected — no federal limit |
| Turbidity | Physical & aggregate | 0.06 NTU (Average) | Ch | No federal limit | Detected — no federal limit |

## What these contaminants are

- **Chlorine** — A disinfectant added to drinking water to kill bacteria and viruses. Effective and necessary, but high residual levels can cause taste and odor issues; the EPA caps the residual disinfectant level.
- **HAA5** — Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter. Long-term exposure above the federal limit is associated with an increased cancer risk.
- **TTHM** — Total trihalomethanes — a group of four chemicals (including chloroform) formed when chlorine reacts with natural organic matter. Long-term exposure above the federal limit is linked to liver, kidney, and central-nervous-system effects and increased cancer risk.
- **Fluoride** — A mineral often added to drinking water to help prevent tooth decay. Beneficial at low levels, but long-term exposure above the federal limit can cause bone disease and tooth mottling.
- **Nitrate** — A compound from fertilizer runoff, septic systems, and erosion of natural deposits. Levels above the federal limit can cause 'blue baby syndrome,' a serious oxygen-transport condition in infants.
- **Nitrite** — A compound from fertilizer runoff, sewage, and erosion of natural deposits. Like nitrate, elevated levels can cause 'blue baby syndrome' in infants.
- **Barium** — A metal from erosion of natural deposits and industrial discharge. Long-term exposure above the federal limit can raise blood pressure.
- **Chromium, Total** — Total chromium — the sum of all chromium forms, from natural deposits and industrial discharge. Long-term exposure above the federal limit can cause allergic dermatitis; includes hexavalent chromium.
- **Copper** — A metal that enters water from corroding household plumbing. Short-term exposure causes stomach distress; long-term exposure can damage the liver and kidneys.
- **Lead** — A toxic metal that leaches into water from old service lines, solder, and plumbing fixtures. There is no safe level of lead; it harms brain development in children and raises blood pressure in adults. The EPA sets an action level, not a health goal above zero.
- **Nickel** — A metal from natural deposits and industrial discharge. Long-term exposure can cause skin and other effects; monitored under EPA rules.
- **Hexafluoropropylene oxide dimer acid** — HFPO-DA ('GenX chemicals'), a newer-generation PFAS replacement compound. Regulated by the EPA at 10 parts per trillion and included in the PFAS Hazard Index.
- **Perfluorohexanesulfonic acid** — Perfluorohexanesulfonic acid, a PFAS 'forever chemical.' Regulated by the EPA at 10 parts per trillion and included in the PFAS Hazard Index.
- **Perfluorononanoic acid** — Perfluorononanoic acid, a PFAS 'forever chemical.' Regulated by the EPA at 10 parts per trillion and included in the PFAS Hazard Index.
- **PFOA** — Perfluorooctanoic acid, a PFAS 'forever chemical' once used in nonstick and stain-resistant products. Linked to cancer, liver damage, and immune effects; the EPA set an enforceable limit of 4 parts per trillion.
- **PFOS** — Perfluorooctanesulfonic acid, a PFAS 'forever chemical' once used in firefighting foam and coatings. Linked to cancer, thyroid disease, and immune effects; the EPA set an enforceable limit of 4 parts per trillion.
- **TOC** — Total organic carbon — a measure of organic material dissolved in the water. Not harmful itself, but it is the raw material that forms disinfection byproducts; removal is a treatment requirement.
- **Turbidity** — A measure of cloudiness from suspended particles in the water. High turbidity can shelter microbes from disinfection; the EPA enforces it through a treatment-technique standard.

## How to read this

- A water-quality report covers an entire service area, not a single address.
- 'Federal limit' is the EPA standard (MCL, action level, treatment technique, etc.) that the measured level is compared against.
- 'At or above the federal limit' means the utility's own reported figure met or exceeded that standard.

_Figures are the utility's own published numbers. Generated 2026-05-25 from thewatermap.com._