# Cary, NC — Drinking Water Quality (2025)

> Contaminant levels for the Cary, NC public water system from its 2025 Consumer Confidence Report, compared to federal limits.

- Page: https://www.thewatermap.com/water/nc/cary/2025
- JSON API: https://www.thewatermap.com/api/water/nc/cary/2025
- 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: 2025
- Contaminants measured: 18
- Contaminants with a federal limit: 11
- 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 |
|---|---|---|---|---|---|
| Chloramine | Disinfectants | 1.33–3.91 mg/L (Range) | System-wide | 4 mg/L (MRDL) | Approaching the limit |
| Chlorine | Disinfectants | 0.37–3.29 mg/L (Range) | System-wide | 4 mg/L (MRDL) | Approaching the limit |
| Bromate | Disinfection byproducts | 0–3 ug/L (Range) | System-wide | 10 ug/L (MCL) | Within the limit |
| HAA5 | Disinfection byproducts | 17 ug/L (Running annual avg) | System-wide | 60 ug/L (MCL) | Within the limit |
| TTHM | Disinfection byproducts | 37 ug/L (Running annual avg) | System-wide | 80 ug/L (MCL) | Within the limit |
| Fluoride | Inorganic chemicals | 0.65 mg/L (Reported level) | System-wide | 4 mg/L (MCL) | Within the limit |
| Copper | Metals | 0.096 mg/L (90th percentile) | At the tap | 1.3 mg/L (Action level) | Within the limit |
| Lead | Metals | Not detected ug/L (90th percentile) | At the tap | 15 ug/L (Action level) | Within the limit |
| Perfluorobutanesulfonic acid | PFAS ("forever chemicals") | Not detected (Average) | Detection | No federal limit | Detected — no federal limit |
| Perfluoroheptanoic acid | PFAS ("forever chemicals") | 1.1 (Average) | Detection | No federal limit | Detected — no federal limit |
| Perfluorohexanesulfonic acid | PFAS ("forever chemicals") | Not detected (Average) | Detection | 10 (MCL) | Within the limit |
| Perfluorohexanoic acid | PFAS ("forever chemicals") | 5.1 (Average) | Detection | No federal limit | Detected — no federal limit |
| Perfluoropentanoic acid | PFAS ("forever chemicals") | 6 (Average) | Detection | No federal limit | Detected — no federal limit |
| PFBA | PFAS ("forever chemicals") | 5.9 (Average) | Detection | No federal limit | Detected — no federal limit |
| PFOA | PFAS ("forever chemicals") | 1.3 (Average) | Detection | 4 (MCL) | Within the limit |
| PFOS | PFAS ("forever chemicals") | Not detected (Average) | Detection | 4 (MCL) | Within the limit |
| TOC | Physical & aggregate | 1.36–1.72 (Range) | System-wide | No federal limit | Detected — no federal limit |
| Turbidity | Physical & aggregate | 0.1 NTU (Reported level) | System-wide | No federal limit | Detected — no federal limit |

## What these contaminants are

- **Chloramine** — A longer-lasting disinfectant made by combining chlorine with ammonia. Holds disinfection further into the pipe network, but is regulated under the same residual-disinfectant cap as chlorine.
- **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.
- **Bromate** — A disinfection byproduct formed when bromide-containing water is treated with ozone. Classified as a probable human carcinogen; the EPA sets a strict maximum contaminant 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.
- **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.
- **Perfluorobutanesulfonic acid** — Perfluorobutanesulfonic acid, a shorter-chain PFAS 'forever chemical.' Has no standalone limit but is part of the EPA PFAS Hazard Index that limits PFAS in combination.
- **Perfluoroheptanoic acid** — Perfluoroheptanoic acid, a PFAS 'forever chemical.' Monitored under EPA rules; persistent in the environment.
- **Perfluorohexanesulfonic acid** — Perfluorohexanesulfonic acid, a PFAS 'forever chemical.' Regulated by the EPA at 10 parts per trillion and included in the PFAS Hazard Index.
- **Perfluorohexanoic acid** — Perfluorohexanoic acid, a shorter-chain PFAS 'forever chemical.' Monitored under EPA rules; persistent and widely detected.
- **Perfluoropentanoic acid** — Perfluoropentanoic acid, a shorter-chain PFAS 'forever chemical.' Monitored under EPA rules; persistent in the environment.
- **PFBA** — Perfluorobutanoic acid, a shorter-chain PFAS 'forever chemical.' Monitored under EPA rules; persistent in the environment and the human body.
- **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._