# Simi Valley, CA — Drinking Water Quality (2024)

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

- Page: https://www.thewatermap.com/water/ca/simi-valley/2024
- JSON API: https://www.thewatermap.com/api/water/ca/simi-valley/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: 36
- Contaminants with a federal limit: 25
- Contaminants at or above the federal limit: 0
- Part of The Water Map — https://www.thewatermap.com

## Contaminants measured

| Contaminant | Category | Measured level | Sampling context | Federal limit | Status |
|---|---|---|---|---|---|
| Chlorine | Disinfectants | 2.3–2.8 mg/L (Average) | Metropolitan Jensen Plant | No federal limit | Detected — no federal limit |
| Bromate | Disinfection byproducts | 3.1 ug/L (Average) | Metropolitan Jensen Plant | 10 ug/L (MCL) | Within the limit |
| Chlorate | Disinfection byproducts | 71 ug/L (Average) | Metropolitan Jensen Plant | 800 ug/L (Public health goal) | Within the limit |
| HAA5 | Disinfection byproducts | 12–22 ug/L (Average) | Metropolitan Jensen Plant | 60 ug/L (MCL) | Within the limit |
| TTHM | Disinfection byproducts | 21.8–36 ug/L (Average) | Metropolitan Jensen Plant | 80 ug/L (MCL) | Within the limit |
| Chloride | Inorganic chemicals | 99 mg/L (Average) | Calleguas Lake Bard Water Filtration Plant | 500 mg/L (MCL) | Within the limit |
| Fluoride | Inorganic chemicals | 0.7–1 mg/L (Average) | Metropolitan Jensen Plant | 2 mg/L (MCL) | Within the limit |
| Nitrate | Inorganic chemicals | 0.69 mg/L (Average) | Tapo Canyon Water Treatment Plant | 10 mg/L (MCL) | Within the limit |
| Sulfate | Inorganic chemicals | 125 mg/L (Average) | Tapo Canyon Water Treatment Plant | 500 mg/L (MCL) | Within the limit |
| Aluminum | Metals | 62 ug/L (Average) | Metropolitan Jensen Plant | 200 ug/L (MCL) | Within the limit |
| Arsenic | Metals | 3 ug/L (Average) | Calleguas Lake Bard Water Filtration Plant | 10 ug/L (MCL) | Within the limit |
| Boron | Metals | 0.28 mg/L (Average) | Calleguas Lake Bard Water Filtration Plant | 1 mg/L (Public health goal) | Within the limit |
| Calcium | Metals | 58 mg/L (Average) | Tapo Canyon Water Treatment Plant | No federal limit | Detected — no federal limit |
| Chromium, Total | Metals | 0.09 ug/L (Average) | Tapo Canyon Water Treatment Plant | 10 ug/L (MCL) | Within the limit |
| Copper | Metals | 0.11 mg/L (90th percentile) | At the tap | 1.3 mg/L (Action level) | Within the limit |
| Lead | Metals | 0.001 mg/L (90th percentile) | At the tap | 15 mg/L (Action level) | Within the limit |
| Magnesium | Metals | 17 mg/L (Average) | Calleguas Lake Bard Water Filtration Plant | No federal limit | Detected — no federal limit |
| Potassium | Metals | 4 mg/L (Average) | Calleguas Lake Bard Water Filtration Plant | No federal limit | Detected — no federal limit |
| Selenium | Metals | 11 ug/L (Average) | Tapo Canyon Water Treatment Plant | 50 ug/L (MCL) | Within the limit |
| Sodium | Metals | 89 mg/L (Average) | Calleguas Lake Bard Water Filtration Plant | No federal limit | Detected — no federal limit |
| Vanadium | Metals | 4.3 ug/L (Average) | Tapo Canyon Water Treatment Plant | 50 ug/L (Public health goal) | Within the limit |
| Zinc | Metals | 0.06 mg/L (Average) | Calleguas Lake Bard Water Filtration Plant | 5 mg/L (MCL) | Within the limit |
| Total Coliform | Microbial | 0 % (Highest single sample) | System-wide | 5 % (MCL) | None detected |
| Alkalinity | Physical & aggregate | 140 mg/L (Average) | Tapo Canyon Water Treatment Plant | No federal limit | Detected — no federal limit |
| Color | Physical & aggregate | 1 % (Average) | Metropolitan Jensen Plant | 15 % (MCL) | Within the limit |
| Hardness | Physical & aggregate | 195 mg/L (Average) | Tapo Canyon Water Treatment Plant | No federal limit | Detected — no federal limit |
| Odor | Physical & aggregate | 1 % (Average) | Metropolitan Jensen Plant | 3 % (MCL) | Within the limit |
| pH | Physical & aggregate | 8.3 % (Average) | Metropolitan Jensen Plant | No federal limit | Detected — no federal limit |
| Specific Conductance | Physical & aggregate | 782 % (Average) | Calleguas Lake Bard Water Filtration Plant | 1600 % (MCL) | Within the limit |
| TOC | Physical & aggregate | 2.7 mg/L (Average) | Calleguas Lake Bard Water Filtration Plant | No federal limit | Detected — no federal limit |
| Total Dissolved Solids | Physical & aggregate | 430 mg/L (Average) | Calleguas Lake Bard Water Filtration Plant | 1000 mg/L (MCL) | Within the limit |
| Turbidity | Physical & aggregate | 0.14 NTU (Average) | Calleguas Lake Bard Water Filtration Plant | No federal limit | Detected — no federal limit |
| Gross Alpha | Radionuclides | 5.62 pCi/L (Average) | Tapo Canyon Water Treatment Plant | 15 pCi/L (MCL) | Within the limit |
| Gross Beta Particle Activity | Radionuclides | 5.5 pCi/L (Average) | Calleguas Lake Bard Water Filtration Plant | 50 pCi/L (MCL) | Within the limit |
| Radon | Radionuclides | 390.5 pCi/L (Average) | Tapo Canyon Water Treatment Plant | No federal limit | Detected — no federal limit |
| Uranium | Radionuclides | 4.2 pCi/L (Average) | Tapo Canyon Water Treatment 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.
- **Chlorate** — A byproduct that can form during disinfection, especially when hypochlorite solutions degrade. Has no enforceable federal limit but is on the EPA contaminant candidate list; high levels can affect the thyroid.
- **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.
- **Chloride** — A naturally occurring salt compound. Regulated only as a secondary (cosmetic) standard; high levels cause a salty taste and can corrode pipes.
- **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.
- **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.
- **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.
- **Chromium, Total** — Total chromium — the sum of all chromium forms, from natural deposits and industrial discharge. Long-term exposure above the federal limit can cause allergic dermatitis; includes hexavalent chromium.
- **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.
- **Selenium** — A trace element from natural deposits and industrial discharge. Essential in tiny amounts, but long-term exposure above the federal limit can cause hair and fingernail loss and circulatory problems.
- **Sodium** — A naturally occurring salt component. Not federally regulated for health; relevant for people on sodium-restricted diets.
- **Zinc** — A naturally occurring metal that can also enter water from corroding pipes. Regulated only as a secondary (cosmetic) standard; high levels cause a metallic taste.
- **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.
- **Color** — A measure of visible tint in the water. Regulated only as a secondary (cosmetic) standard.
- **Hardness** — A measure of dissolved calcium and magnesium minerals. Not federally regulated for health; affects scaling, soap use, and taste.
- **Odor** — A measure of detectable smell in the water. Regulated only as a secondary (cosmetic) standard.
- **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.
- **Specific Conductance** — A measure of how well water conducts electricity, which tracks dissolved mineral content. Not federally regulated for health; used as a proxy for total dissolved solids.
- **TOC** — Total organic carbon — a measure of organic material dissolved in the water. Not harmful itself, but it is the raw material that forms disinfection byproducts; removal is a treatment requirement.
- **Total Dissolved Solids** — Total dissolved solids — the combined content of all dissolved minerals and salts. Regulated only as a secondary (cosmetic) standard; high levels affect taste and hardness.
- **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.
- **Radon** — A naturally occurring radioactive gas that can dissolve into groundwater. No enforceable federal limit in drinking water yet; inhalation of released radon raises lung-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._