# Rochester, MN — Drinking Water Quality (2025)

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

- Page: https://www.thewatermap.com/water/mn/rochester/2025
- JSON API: https://www.thewatermap.com/api/water/mn/rochester/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: 21
- Contaminants with a federal limit: 19
- Contaminants at or above the federal limit: 1
- Part of The Water Map — https://www.thewatermap.com

## Contaminants measured

| Contaminant | Category | Measured level | Sampling context | Federal limit | Status |
|---|---|---|---|---|---|
| Chlorine | Disinfectants | 0.94–1.07 (Range) | of Detected Test Results | 4 (MCLG) | Within the limit |
| HAA5 | Disinfection byproducts | 1.2–5.5 (Range) | of Detected Test Results | 60 (MCL) | Within the limit |
| TTHM | Disinfection byproducts | 4.4–16 (Range) | of Detected Test Results | 80 (MCL) | Within the limit |
| Fluoride | Inorganic chemicals | 0.69–0.72 (Range) | of Detected Test Results | 4 (MCLG) | Within the limit |
| Nitrate | Inorganic chemicals | 0.19 (Maximum) | Average or Highest Single Test Result | 10 (MCLG) | Within the limit |
| Sulfate | Inorganic chemicals | 31.8 (Maximum) | Average Result or Highest Single Test Result | 500 (MCL) | Within the limit |
| Barium | Metals | 0.09 (Maximum) | Average or Highest Single Test Result | 2 (MCLG) | Within the limit |
| Copper | Metals | 0.76 % (90th percentile) | At the tap | 1.3 % (MCLG) | Within the limit |
| Lead | Metals | 7.46 % (90th percentile) | At the tap | 0 % (MCLG) | Detected — no federal limit |
| Lithium | Metals | 0–10.8 (Range) | of Detected Test Results | 10 (MCL) | At or above the limit |
| Sodium | Metals | 8.77 (Maximum) | Average Result or Highest Single Test Result | 20 (MCL) | Within the limit |
| 6:2 Fluorotelomer sulfonic acid (6:2 FTS) | PFAS ("forever chemicals") | 1.2 (Maximum) | Average Result or Highest Single Test Result | No federal limit | Detected — no federal limit |
| Perfluorobutanesulfonic acid | PFAS ("forever chemicals") | 0.55 (Maximum) | Average Result or Highest Single Test Result | 100 (MCL) | Within the limit |
| Perfluorohexanesulfonic acid | PFAS ("forever chemicals") | 0–4.8 (Range) | of Detected Test Results | 47 (MCL) | Within the limit |
| Perfluorohexanoic acid | PFAS ("forever chemicals") | 0–0.89 (Range) | of Detected Test Results | 200 (MCL) | Within the limit |
| Perfluoropentanesulfonic acid (PFPeS) | PFAS ("forever chemicals") | 0–0.45 (Range) | of Detected Test Results | No federal limit | Detected — no federal limit |
| PFBA | PFAS ("forever chemicals") | 0–3.4 (Range) | of Detected Test Results | 7000 (MCL) | Within the limit |
| PFOA | PFAS ("forever chemicals") | 0–0.97 (Range) | of Detected Test Results | 0 (MCLG) | Detected — no federal limit |
| PFOS | PFAS ("forever chemicals") | 0–2.7 (Range) | of Detected Test Results | 0 (MCLG) | Detected — no federal limit |
| Combined Radium | Radionuclides | 4.9 (Maximum) | Average or Highest Single Test Result | 0 (MCLG) | Detected — no federal limit |
| Gross Alpha | Radionuclides | 4.3–14 (Range) | of Detected Test Results | 0 (MCLG) | 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.
- **Sulfate** — A naturally occurring mineral from rock and soil. No health-based federal limit; high levels can have a laxative effect and a bitter taste.
- **Barium** — A metal from erosion of natural deposits and industrial discharge. Long-term exposure above the federal limit can raise blood pressure.
- **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.
- **Lithium** — A naturally occurring element found in some groundwater. No enforceable federal limit; on the EPA contaminant candidate list for further study.
- **Sodium** — A naturally occurring salt component. Not federally regulated for health; relevant for people on sodium-restricted diets.
- **6:2 Fluorotelomer sulfonic acid (6:2 FTS)** — 6:2 fluorotelomer sulfonic acid, a PFAS-related compound. Monitored under EPA rules as part of broad PFAS surveillance.
- **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.
- **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.
- **Perfluoropentanesulfonic acid (PFPeS)** — Perfluoropentanesulfonic acid, a 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.
- **Combined Radium** — Combined radium-226 and radium-228 — naturally occurring radioactive elements. Long-term exposure above the federal limit increases the risk of bone cancer.
- **Gross Alpha** — Gross alpha particle activity — a combined measure of alpha-emitting radioactive substances. Long-term exposure above the federal limit increases cancer risk.

## 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._