# California Water Service Co-leona Valley — San Jose, Ca, CA — Drinking Water Quality (2020)

> Contaminant levels for the California Water Service Co-leona Valley — San Jose, Ca, CA public water system from its 2020 Consumer Confidence Report, compared to federal limits.

- Page: https://www.thewatermap.com/water/ca/california-water-service-co-leona-valley-san-jose-ca/2020
- JSON API: https://www.thewatermap.com/api/water/ca/california-water-service-co-leona-valley-san-jose-ca/2020
- 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: 2020
- Contaminants measured: 22
- Contaminants with a federal limit: 10
- 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 |
|---|---|---|---|---|---|
| HAA5 | Disinfection byproducts | 14 ug/L (Average) | Distribution System-Wide Highest Annual | No federal limit | Within the limit |
| TTHM | Disinfection byproducts | 44 ug/L (Average) | Distribution System-Wide Highest Annual | No federal limit | Within the limit |
| Asbestos | Inorganic chemicals | 9.5 MFL (Average) | Groundwater | 7 MFL (MCL) | At or above the limit |
| Fluoride | Inorganic chemicals | 0.31 mg/L (Average) | Groundwater | 4 mg/L (MCL) | Within the limit |
| Nitrate | Inorganic chemicals | 3 mg/L (Average) | Groundwater | 10 mg/L (MCL) | Within the limit |
| Barium | Metals | Not detected mg/L (Average) | Groundwater | 2 mg/L (MCL) | Within the limit |
| Boron | Metals | Not detected mg/L (Average) | Groundwater | 1 mg/L (NL) | Detected — no federal limit |
| Calcium | Metals | 71 mg/L (Average) | Groundwater | No federal limit | Detected — no federal limit |
| Copper | Metals | 0.26 mg/L (90th percentile) | Distribution System-Wide | 1.3 mg/L (Action level) | Within the limit |
| Lead | Metals | Not detected ug/L (90th percentile) | Distribution System-Wide | No federal limit | None detected |
| Magnesium | Metals | 26 mg/L (Average) | Groundwater | No federal limit | Detected — no federal limit |
| Potassium | Metals | 1.3 mg/L (Average) | Groundwater | No federal limit | Detected — no federal limit |
| Sodium | Metals | 60 mg/L (Average) | Avek | No federal limit | Detected — no federal limit |
| Vanadium | Metals | 5.6 ug/L (Average) | Groundwater | 50 ug/L (NL) | Detected — no federal limit |
| Escherichia coli (E. coli) | Microbial | 0 (Maximum) | Monthly | No federal limit | None detected |
| Total Coliform | Microbial | 0 (Maximum) | Monthly | No federal limit | None detected |
| Chlorine Free | Other | 0.96 mg/L (Average) | Distribution System-Wide | 4 mg/L (MCL) | Within the limit |
| Chromium | Other | 1.4 ug/L (Average) | Groundwater | 0.02 ug/L (Public health goal) | Within the limit |
| Alkalinity | Physical & aggregate | 178 mg/L (Average) | Groundwater | No federal limit | Detected — no federal limit |
| Hardness | Physical & aggregate | 284 mg/L (Average) | Groundwater | No federal limit | Detected — no federal limit |
| pH | Physical & aggregate | 7.5 (Average) | Groundwater | No federal limit | Detected — no federal limit |
| Uranium | Radionuclides | 2.1 pCi/L (Average) | Groundwater | 20 pCi/L (MCL) | Detected — no federal limit |

## What these contaminants are

- **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.
- **Barium** — A metal from erosion of natural deposits and industrial discharge. Long-term exposure above the federal limit can raise blood pressure.
- **Boron** — A naturally occurring element from rock and soil. No enforceable federal limit; the EPA has issued a health advisory level.
- **Calcium** — A naturally occurring mineral that contributes to water hardness. Not federally regulated for health; affects scaling and taste.
- **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.
- **Magnesium** — A naturally occurring mineral that contributes to water hardness. Not federally regulated for health; affects scaling and taste.
- **Potassium** — A naturally occurring mineral from rock and soil. Not federally regulated for health.
- **Sodium** — A naturally occurring salt component. Not federally regulated for health; relevant for people on sodium-restricted diets.
- **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.
- **Alkalinity** — A measure of the water's capacity to neutralize acids. Not federally regulated for health; relevant to corrosion control and treatment.
- **Hardness** — A measure of dissolved calcium and magnesium minerals. Not federally regulated for health; affects scaling, soap use, and taste.
- **pH** — A measure of how acidic or basic the water is. Regulated only as a secondary standard; very low or high pH can corrode pipes or affect taste.
- **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 2026-06-04 from thewatermap.com._