# Chula Vista Otay, CA — Drinking Water Quality (2024)

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

- Page: https://www.thewatermap.com/water/ca/chula-vista-otay/2024
- JSON API: https://www.thewatermap.com/api/water/ca/chula-vista-otay/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: 18
- Contaminants with a federal limit: 15
- 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 | 0.2–3.6 mg/L (Average) | System-wide | No federal limit | Detected — no federal limit |
| Bromate | Disinfection byproducts | 0–8.5 ug/L (Reported level) | Twin Oaks Plant | 10 ug/L (MCL) | Approaching the limit |
| HAA5 | Disinfection byproducts | 3.2–24.4 ug/L (Average) | System-wide | No federal limit | Detected — no federal limit |
| TTHM | Disinfection byproducts | 10.5–60.6 ug/L (Average) | System-wide | No federal limit | Detected — no federal limit |
| Fluoride | Inorganic chemicals | 0.5–0.8 mg/L (Average) | System-wide | 2 mg/L (MCL) | Within the limit |
| Aluminum | Metals | 64–230 ug/L (Reported level) | Helix Plant | 1000 ug/L (MCL) | Within the limit |
| Arsenic | Metals | 0–5 ug/L (Reported level) | Helix Plant | 10 ug/L (MCL) | Within the limit |
| Barium | Metals | 95–122 ug/L (Reported level) | Twin Oaks Plant | 1000 ug/L (MCL) | Within the limit |
| Copper | Metals | 0 mg/L (Average) | System-wide | 1.3 mg/L (Action level) | None detected |
| Lead | Metals | 0 ug/L (Average) | System-wide | 15 ug/L (Action level) | None detected |
| Lithium | Metals | 0–28.9 ug/L (Reported level) | System-wide | 9 ug/L (MCL) | At or above the limit |
| Manganese | Metals | 0–9.2 ug/L (Reported level) | System-wide | 50 ug/L (MCL) | Within the limit |
| Escherichia coli (E. coli) | Microbial | 0 (Average) | System-wide | 0 (MCL) | None detected |
| Total Coliform | Microbial | 0 % (Average) | System-wide | 5 % (MCL) | None detected |
| Turbidity | Physical & aggregate | 0.3 % (Average) | System-wide | 95 % (MCL) | Within the limit |
| Gross Alpha | Radionuclides | 0–4 pCi/L (Reported level) | Skinner Plant | 15 pCi/L (MCL) | Within the limit |
| Gross Beta Particle Activity | Radionuclides | 0–5 pCi/L (Reported level) | Skinner Plant | 50 pCi/L (MCL) | Within the limit |
| Uranium | Radionuclides | 2–3 pCi/L (Reported level) | Twin Oaks Plant | 20 pCi/L (MCL) | Within the 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.
- **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.
- **Aluminum** — A common element sometimes used as a treatment coagulant. Regulated only as a secondary (cosmetic) standard; high levels can discolor water.
- **Arsenic** — A naturally occurring element that also enters water from industry and agriculture. A known human carcinogen; long-term exposure is linked to skin, bladder, and lung cancer.
- **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.
- **Manganese** — A naturally occurring metal from soil and rock. No enforceable federal limit; high levels stain fixtures and laundry and can affect taste, with a health advisory for infants.
- **Escherichia coli (E. coli)** — Escherichia coli — bacteria found in the gut of humans and animals. Its presence in drinking water indicates fecal contamination and a real risk of waterborne illness.
- **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.
- **Gross Alpha** — Gross alpha particle activity — a combined measure of alpha-emitting radioactive substances. Long-term exposure above the federal limit increases cancer risk.
- **Gross Beta Particle Activity** — Gross beta particle activity — a combined measure of beta-emitting radioactive substances. Long-term exposure above the federal screening level increases cancer risk.
- **Uranium** — A naturally occurring radioactive metal from erosion of natural deposits. Long-term exposure above the federal limit can damage the kidneys and increase 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._