# Concord, CA — Drinking Water Quality (2024)

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

- Page: https://www.thewatermap.com/water/ca/concord/2024
- JSON API: https://www.thewatermap.com/api/water/ca/concord/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: 15
- Contaminants with a federal limit: 14
- Contaminants at or above the federal limit: 2
- Part of The Water Map — https://www.thewatermap.com

## Contaminants measured

| Contaminant | Category | Measured level | Sampling context | Federal limit | Status |
|---|---|---|---|---|---|
| Chloramine | Disinfectants | 2.6 mg/L (Running annual avg) | Highest Quarterly | 4 mg/L (MCLG) | Within the limit |
| Bromate | Disinfection byproducts | Not detected ug/L (Running annual avg) | Highest Quarterly | 0.1 ug/L (MCLG) | Within the limit |
| Chlorite | Disinfection byproducts | 0.2 mg/L (Running annual avg) | Highest Quarterly | 0.05 mg/L (MCLG) | At or above the limit |
| HAA5 | Disinfection byproducts | 10 ug/L (Running annual avg) | Highest Quarterly | 60 ug/L (MCL) | Within the limit |
| TTHM | Disinfection byproducts | 62 ug/L (Running annual avg) | Highest Quarterly | 80 ug/L (MCL) | Within the limit |
| Asbestos | Inorganic chemicals | Not detected MFL (Average) | System-wide | 7 MFL (MCLG) | Within the limit |
| Fluoride | Inorganic chemicals | 0.8 mg/L (Average) | System-wide | 1 mg/L (MCLG) | Approaching the limit |
| Nitrate | Inorganic chemicals | 1.2 mg/L (Average) | System-wide | 10 mg/L (MCLG) | Within the limit |
| Aluminum | Metals | 0.06 mg/L (Average) | System-wide | 0.6 mg/L (MCLG) | Within the limit |
| Chromium, Hexavalent | Metals | 0.11 ug/L (Average) | System-wide | 0.02 ug/L (MCLG) | At or above the limit |
| Copper | Metals | 0.15 mg/L (90th percentile) | At the tap | 0.3 mg/L (MCLG) | Within the limit |
| Lead | Metals | Not detected ug/L (90th percentile) | At the tap | 0.2 ug/L (MCLG) | None detected |
| Lithium | Metals | 11.5 ug/L (Average) | System-wide | No federal limit | Detected — no federal limit |
| Total Coliform | Microbial | 0.5 % (Average) | System-wide | 5 % (MCL) | Within the limit |
| Turbidity | Physical & aggregate | 0.44 NTU (Range) | System-wide | 95 NTU (MCL) | Within the 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.
- **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.
- **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.
- **Aluminum** — A common element sometimes used as a treatment coagulant. Regulated only as a secondary (cosmetic) standard; high levels can discolor water.
- **Chromium, Hexavalent** — Hexavalent chromium ('chromium-6') — the more toxic form of chromium. A known carcinogen by inhalation; regulated nationally only within the total-chromium limit, with stricter limits in some states.
- **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.
- **Total Coliform** — A group of bacteria used as an indicator of overall water-system sanitation. Coliforms themselves are usually harmless, but their presence signals that disease-causing organisms could enter the system.
- **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._