Drinking water quality · 2025
· Verified
What's in Rancho Estates Mutual Water Co., CA tap water
85 contaminants were measured in the Rancho Estates Mutual Water Co., CA water system's 2025 annual report. Each is shown below against its federal limit — 1 sit at or above that limit.
- Reporting year
- 2025
- Contaminants measured
- 85
- Over federal limit
- 1
- Approaching the limit
- 1
- Worst contaminant
- Gross Alpha
- Service area
- CA
1.2× the limit
state-level CCR
At or above the federal limit
Approaching the limit (≥ 80%)
Where your water comes from · EPA SDWIS
Rancho Estates Mutual Water Co., CA's drinking water comes from ground water, drawn from 4 sources.
Source
4ground water
- WELL · 4
Treatment
3treatment plants
- WELL 08 DISINFECTION
- NITRATAX BLENDING MONITOR
- WELL 12 DISINFECTION
Distribution
0storage units
Also buys water from YUIMA MUNICIPAL WATER DISTRICT.
Source: EPA SDWIS facilities inventory. Methodology.
Historical readings · EPA Six-Year Review (2012–2019)
3 contaminants historically over EPA limits in Rancho Estates Mutual Water Co., CA
Every U.S. public water system reports compliance-monitoring data to EPA. The Six-Year Review releases the 2012–2019 window as a single dataset — here's what your system reported, year by year. Values shown are the highest detection per analyte per year, compared to the federal MCL.
| Contaminant | Worst detection | EPA limit | Years (2012–2019) |
|---|---|---|---|
THALLIUM worst: 2012 | 0.038 mg/L 19.0× | 0.002 mg/L | '12 |
NITRATE worst: 2019 | 17 mg/L 1.7× | 10 mg/L | '12'13'14'15'16'17'18'19 |
ANTIMONY worst: 2014 | 0.0065 mg/L 1.1× above national p90 | 0.006 mg/L | '12'14 |
SELENIUM worst: 2012 | 0.04 mg/L within | 0.05 mg/L | '12'17'18 |
ARSENIC worst: 2012 | 0.0071 mg/L within near national p90 | 0.01 mg/L | '12'17'18 |
FLUORIDE worst: 2014 | 0.85 mg/L within | 4 mg/L | '12'14'17'18 |
BARIUM worst: 2014 | 0.084 mg/L within below national p90 | 2 mg/L | '12'14'17'18 |
URANIUM worst: 2019 | 0.116 ug/L within 5.5× the national p90 | 30 ug/L | '13'16'17'18'19 |
TOLUENE worst: 2017 | 0.0036 mg/L within | 1 mg/L | '17 |
LEAD worst: 2012 | 0.18 mg/L | — | '12 |
PWSID CA3700936 · Source: EPA Six-Year Review 4 (2012–2019). Values are the highest detection in each calendar year; non-detect years are omitted. Year tags above show every year with a detection.
Radionuclides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Gross AlphaGross alpha particle activity — a combined measure of alpha-emitting radioactive substances. | 18.4 PCI/LAverageSource water | 15 PCI/LMCL | At or above the limit |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Total Dissolved SolidsTotal dissolved solids — the combined content of all dissolved minerals and salts. | 642.5 MG/LAverageSource water | 1000 MG/LMCL | Within the limit |
| Specific ConductanceA measure of how well water conducts electricity, which tracks dissolved mineral content. | 985 UMHO/CMAverageSource water | 1600 UMHO/CMMCL | Within the limit |
| ColorA measure of visible tint in the water. | Not detected UNITSHighest single sampleSource water | 15 UNITSMCL | None detected |
| OdorA measure of detectable smell in the water. | Not detected TONHighest single sampleSource water | 3 TONMCL | None detected |
| TurbidityA measure of cloudiness from suspended particles in the water. | Not detected NTUHighest single sampleSource water | 5 NTUMCL | None detected |
| AlkalinityA measure of the water's capacity to neutralize acids. | 63.5 MG/LAverageSource water | None set | Detected — no federal limit |
| HardnessA measure of dissolved calcium and magnesium minerals. | 280 MG/LAverageSource water | None set | Detected — no federal limit |
| pHA measure of how acidic or basic the water is. | 7.675 PHAverageSource water | None set | Detected — no federal limit |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| SulfateA naturally occurring mineral from rock and soil. | 285 MG/LAverageSource water | 500 MG/LMCL | Within the limit |
| ChlorideA naturally occurring salt compound. | 77.25 MG/LAverageSource water | 500 MG/LMCL | Within the limit |
| Cyanide | Not detected UG/LHighest single sampleSource water | 150 UG/LMCL | None detected |
| NitriteA compound from fertilizer runoff, sewage, and erosion of natural deposits. | Not detected MG/LHighest single sampleSource water | 1 MG/LMCL | None detected |
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| PerchlorateA chemical used in rocket fuel and fireworks that can also form during disinfection. | 1.0571428571428572 UG/LAverageSource water | 6 UG/LMCL | Within the limit |
| TTHMTotal trihalomethanes — a group of four chemicals (including chloroform) formed when chlorine reacts with natural organic matter. | 3 UG/LAverageDistribution | 80 UG/LMCL | Within the limit |
| HAA5Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter. | Not detected UG/LHighest single sampleDistribution | 60 UG/LMCL | None detected |
| BromodichloromethaneA trihalomethane disinfection byproduct. | 1.02 UG/LAverageDistribution | None set | Detected — no federal limit |
| BromoformA trihalomethane disinfection byproduct. | 0.565 UG/LAverageDistribution | None set | Detected — no federal limit |
| ChloroformA trihalomethane formed when chlorine reacts with organic matter in water. | 0.76 UG/LAverageDistribution | None set | Detected — no federal limit |
| DibromochloromethaneA trihalomethane disinfection byproduct. | 0.82 UG/LAverageDistribution | None set | Detected — no federal limit |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| AluminumA common element sometimes used as a treatment coagulant. | 97.25 UG/LAverageSource water | 1000 UG/LMCL | Within the limit |
| ZincA naturally occurring metal that can also enter water from corroding pipes. | 17.5 UG/LAverageSource water | 5000 UG/LMCL | Within the limit |
| Beryllium | Not detected UG/LHighest single sampleSource water | 4 UG/LMCL | None detected |
| Cadmium | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Chromium, HexavalentHexavalent chromium ('chromium-6') — the more toxic form of chromium. | Not detected UG/LHighest single sampleSource water | 10 UG/LMCL | None detected |
| CopperA metal that enters water from corroding household plumbing. | Not detected UG/LHighest single sampleSource water | 1000 UG/LMCL | None detected |
| IronA naturally occurring metal common in groundwater. | Not detected UG/LHighest single sampleSource water | 300 UG/LMCL | None detected |
| ManganeseA naturally occurring metal from soil and rock. | Not detected UG/LHighest single sampleSource water | 50 UG/LMCL | None detected |
| MercuryA toxic metal from erosion of natural deposits and industrial runoff. | Not detected UG/LHighest single sampleSource water | 2 UG/LMCL | None detected |
| NickelA metal from natural deposits and industrial discharge. | Not detected UG/LHighest single sampleSource water | 100 UG/LMCL | None detected |
| CalciumA naturally occurring mineral that contributes to water hardness. | 45 MG/LAverageSource water | None set | Detected — no federal limit |
| MagnesiumA naturally occurring mineral that contributes to water hardness. | 14.9 MG/LAverageSource water | None set | Detected — no federal limit |
| PotassiumA naturally occurring mineral from rock and soil. | 5.625 MG/LAverageSource water | None set | Detected — no federal limit |
| SodiumA naturally occurring salt component. | 107.75 MG/LAverageSource water | None set | Detected — no federal limit |
Other
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Chromium | 0.875 UG/LAverageSource water | 50 UG/LMCL | Within the limit |
| Carbon Tetrachloride | Not detected UG/LHighest single sampleSource water | 0.5 UG/LMCL | None detected |
| Chlorobenzene | Not detected UG/LHighest single sampleSource water | 70 UG/LMCL | None detected |
| Cis Dichloroethylene 12 | Not detected UG/LHighest single sampleSource water | 6 UG/LMCL | None detected |
| Dbaa | Not detected UG/LHighest single sampleDistribution | None set | None detected |
| Dcaa | Not detected UG/LHighest single sampleDistribution | None set | None detected |
| Deha | Not detected UG/LHighest single sampleSource water | 400 UG/LMCL | None detected |
| Dehp | Not detected UG/LHighest single sampleSource water | 4 UG/LMCL | None detected |
| Dichloroethane 12 | Not detected UG/LHighest single sampleSource water | 0.5 UG/LMCL | None detected |
| Dichloroethylene 11 | Not detected UG/LHighest single sampleSource water | 6 UG/LMCL | None detected |
| Dichloropropane 12 | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Dinoseb | Not detected UG/LHighest single sampleSource water | 7 UG/LMCL | None detected |
| Edb | Not detected UG/LHighest single sampleSource water | 0.05 UG/LMCL | None detected |
| Mbaa | Not detected UG/LHighest single sampleDistribution | None set | None detected |
| Mcaa | Not detected UG/LHighest single sampleDistribution | None set | None detected |
| O Dichlorobenzene | Not detected UG/LHighest single sampleSource water | 600 UG/LMCL | None detected |
| P Dichlorobenzene | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Pce | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Pentachlorophenol | Not detected UG/LHighest single sampleSource water | 1 UG/LMCL | None detected |
| Picloram | Not detected UG/LHighest single sampleSource water | 500 UG/LMCL | None detected |
| Styrene | Not detected UG/LHighest single sampleSource water | 100 UG/LMCL | None detected |
| Tcaa | Not detected UG/LHighest single sampleDistribution | None set | None detected |
| Tce | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Trans Dichloroethylene 12 | Not detected UG/LHighest single sampleSource water | 10 UG/LMCL | None detected |
| Trichlorobenzene 124 | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Trichloroethane 111 | Not detected UG/LHighest single sampleSource water | 200 UG/LMCL | None detected |
| Trichloroethane 112 | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Twofourd | Not detected UG/LHighest single sampleSource water | 70 UG/LMCL | None detected |
| Vinyl Chloride | Not detected UG/LHighest single sampleSource water | 0.5 UG/LMCL | None detected |
VOCs & pesticides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| 1,2,3-TCP | Not detected UG/LHighest single sampleSource water | 0.005 UG/LMCL | None detected |
| AtrazineA widely used agricultural herbicide that reaches water through runoff. | Not detected UG/LHighest single sampleSource water | 1 UG/LMCL | None detected |
| Benzene | Not detected UG/LHighest single sampleSource water | 1 UG/LMCL | None detected |
| Benzo(a)pyrene | Not detected UG/LHighest single sampleSource water | 0.2 UG/LMCL | None detected |
| ChloroethaneA volatile organic compound used in some industrial processes. | Not detected UG/LHighest single sampleSource water | None set | None detected |
| Chloromethane | Not detected UG/LHighest single sampleSource water | None set | None detected |
| Dalapon | Not detected UG/LHighest single sampleSource water | 200 UG/LMCL | None detected |
| Dichlorodifluoromethane | Not detected UG/LHighest single sampleSource water | None set | None detected |
| Dichloromethane | Not detected UG/LHighest single sampleSource water | 5 UG/LMCL | None detected |
| Ethylbenzene | Not detected UG/LHighest single sampleSource water | 300 UG/LMCL | None detected |
| Simazine | Not detected UG/LHighest single sampleSource water | 4 UG/LMCL | None detected |
| XylenesA group of industrial solvents found in gasoline and paint. | Not detected UG/LHighest single sampleSource water | 1750 UG/LMCL | None detected |
Source: Rancho Estates Mutual Water Co., CA's 2025 Consumer Confidence Report — the annual drinking-water report every U.S. utility is required to publish. The numbers on this page are the utility's own. A water-quality report covers an entire service area, not a single address.
People also ask about Rancho Estates Mutual Water Co., CA's water
+Is Rancho Estates Mutual Water Co., CA tap water safe to drink in 2025?
The 2025 Consumer Confidence Report for the Rancho Estates Mutual Water Co., CA water utility lists 1 contaminant at or above the federal limit: Gross Alpha. Whether that means the water is "unsafe" depends on which contaminant, how long the exposure, and individual health factors. The table on this page shows the measured value, the federal threshold, and the regulated statistic used for compliance.
+What contaminants are in Rancho Estates Mutual Water Co., CA tap water?
85 contaminants were measured in Rancho Estates Mutual Water Co., CA's 2025 Consumer Confidence Report, spanning other, metals, and vocs & pesticides. 65 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.
+Which contaminants exceed federal limits in Rancho Estates Mutual Water Co., CA tap water?
One contaminant in Rancho Estates Mutual Water Co., CA's 2025 report sits at or above the federal limit: Gross Alpha (1.2× the limit). The EPA enforces these limits against the regulated reporting statistic — typically a running annual average or 90th percentile — not a one-off sample spike.
+What is the worst contaminant in Rancho Estates Mutual Water Co., CA tap water?
The contaminant with the highest measured value relative to its federal limit in the 2025 report is Gross Alpha, at 1.2× the federal threshold. It belongs to the radionuclides family of contaminants.
+Are any contaminants in Rancho Estates Mutual Water Co., CA tap water approaching the federal limit?
One contaminant is between 80% and 100% of the federal limit in this report: Uranium. Approaching means measured but not in violation — a margin that can close quickly if conditions change.
+Where does the data on this page come from?
Every value is transcribed from Rancho Estates Mutual Water Co., CA's 2025 Consumer Confidence Report — the annual drinking-water report every U.S. public water utility is required by federal law to publish. The original source document is archived and viewable on this site. A water-quality report covers an entire service area, not a single address.
+How often is Rancho Estates Mutual Water Co., CA's water quality data updated?
Each U.S. public water utility publishes one Consumer Confidence Report per year, covering the prior calendar year's measurements. This page reflects the 2025 report; a new report will replace it once the utility publishes its next annual update.
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