# Alameda County Water District — Fremont, Ca, CA — Drinking Water Quality (2023)

> Contaminant levels for the Alameda County Water District — Fremont, Ca, CA public water system from its 2023 Consumer Confidence Report, compared to federal limits.

- Page: https://www.thewatermap.com/water/ca/alameda-county-water-district-fremont-ca/2023
- JSON API: https://www.thewatermap.com/api/water/ca/alameda-county-water-district-fremont-ca/2023
- 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: 2023
- Contaminants measured: 11
- Contaminants with a federal limit: 8
- 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 |
|---|---|---|---|---|---|
| Fluoride | Inorganic chemicals | 0–0.86 mg/L (Average) | Purchased San Francisco Water | 4 mg/L (MCL) | Within the limit |
| Nitrate | Inorganic chemicals | 0.42 mg/L (Average) | Desalinated Water | 10 mg/L (MCL) | Within the limit |
| Copper | Metals | 0.1 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 | No federal limit | Within the limit |
| Nitrate Nitrite | Other | 0.42 mg/L (Average) | Desalinated Water | 10 mg/L (MCL) | Within the limit |
| Perfluorobutanesulfonic acid | PFAS ("forever chemicals") | Not detected ng/L (Average) | Blended Water | 2 ng/L (Public health goal) | Detected — no federal limit |
| Perfluorohexanesulfonic acid | PFAS ("forever chemicals") | Not detected ng/L (Average) | Blended Water | 10 ng/L (MCL) | Within the limit |
| PFAS | PFAS ("forever chemicals") | 0.05 (Average) | Desalinated Water | No federal limit | Detected — no federal limit |
| PFOA | PFAS ("forever chemicals") | Not detected ng/L (Average) | Blended Water | 4 ng/L (MCL) | Within the limit |
| PFOS | PFAS ("forever chemicals") | Not detected ng/L (Average) | Desalinated Water | 4 ng/L (MCL) | Within the limit |
| Turbidity | Physical & aggregate | 2.1 NTU (Average) | Purchased San Francisco Water | No federal limit | At or above the limit |

## What these contaminants are

- **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.
- **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.
- **Perfluorohexanesulfonic acid** — Perfluorohexanesulfonic 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.
- **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 2026-06-04 from thewatermap.com._