Drinking water quality · 2026
· Verified
What's in Cal-water Service Co.-chico, CA tap water
124 contaminants were measured in the Cal-water Service Co.-chico, CA water system's 2026 annual report. Each is shown below against its federal limit.
- Reporting year
- 2026
- Contaminants measured
- 124
- Over federal limit
- 0
- Approaching the limit
- 1
- Service area
- CA
state-level CCR
Approaching the limit (≥ 80%)
PFAS — EPA UCMR5 (2023–2025)
3 PFAS compounds above EPA limits in Cal-water Service Co.-chico, CA
The EPA finalized the first-ever federal drinking-water limits for six PFAS compounds in April 2024. These numbers come straight from EPA's UCMR5 lab dataset — every U.S. system serving more than 3,300 people tested every PFAS sample at an entry point to its distribution system. PFAS not listed below were either tested and not detected, or not yet sampled.
PFOS (Perfluorooctane sulfonic acid)
● Over EPA limit (5.6×)Measured 22.5 ng/LEPA limit 4 ng/LSample year 2024Samples 11 detect / 47
above national p90 (19.900000000000006 ng/L across detecting U.S. systems)
PFHxS (Perfluorohexane sulfonic acid)
● Over EPA limit (2.2×)Measured 22.1 ng/LEPA limit 10 ng/LSample year 2024Samples 14 detect / 47
above national p90 (12.049999999999997 ng/L across detecting U.S. systems)
PFOA (Perfluorooctanoic acid)
● Over EPA limit (1.7×)Measured 6.8 ng/LEPA limit 4 ng/LSample year 2024Samples 2 detect / 47
below national p90 (13.649999999999999 ng/L across detecting U.S. systems)
PFBS
● Detected (no federal limit)Measured 9.6 ng/LSample year 2024Samples 4 detect / 47
near national p90 (13.909999999999979 ng/L across detecting U.S. systems)
Lithium
● Detected (no federal limit)Measured 11.7 mg/LSample year 2024Samples 1 detect / 47
below national p90 (76.59999999999991 mg/L across detecting U.S. systems)
PFHxA
● Detected (no federal limit)Measured 6 ng/LSample year 2024Samples 2 detect / 47
below national p90 (12.190000000000003 ng/L across detecting U.S. systems)
PFPeA
● Detected (no federal limit)Measured 5.3 ng/LSample year 2024Samples 2 detect / 47
below national p90 (15.95999999999999 ng/L across detecting U.S. systems)
PWSID CA0410002 · Source: EPA UCMR5. Limits per EPA's April 2024 PFAS National Primary Drinking Water Regulation. PFAS values reported in nanograms per liter (ng/L) — note that 1 ng/L = 1 part per trillion.
Where your water comes from · EPA SDWIS
Cal-water Service Co.-chico, CA's drinking water comes from ground water, drawn from 54 sources.
Source
54ground water
- WELL 20-01
- WELL 75-01
- WELL 21-01
- WELL 24-01 - STANDBY
- + 50 more
Treatment
65treatment plants
- WELL 50-01 - CHLORINATED XCLD
- WELL 62-01 - CHLORINATED XCLD
- WELL 37-01 - CHLORINATED XCLD
- + 62 more
Distribution
0storage units
Source: EPA SDWIS facilities inventory. Methodology.
Historical readings · EPA Six-Year Review (2012–2019)
2 contaminants historically over EPA limits in Cal-water Service Co.-chico, 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) |
|---|---|---|---|
PCE worst: 2016 | 0.22 mg/L 44.0× | 0.005 mg/L | '12'13'16'17'18'19 |
NITRATE worst: 2012 | 13.5 mg/L 1.4× | 10 mg/L | '12'13'14'15'16'17'18'19 |
NITRATE NITRITE worst: 2018 | 6.9 mg/L within | 10 mg/L | '16'17'18'19 |
ARSENIC worst: 2012 | 0.0025 mg/L within below national p90 | 0.01 mg/L | '12'13'14'15 |
TCE worst: 2012 | 0.00118 mg/L within | 0.005 mg/L | '12'13'14'15'16 |
NITRITE worst: 2013 | 0.195 mg/L within | 1 mg/L | '13 |
DICHLOROMETHANE worst: 2017 | 0.00085 mg/L within | 0.005 mg/L | '17 |
TTHM worst: 2013 | 0.0118 mg/L within | 0.08 mg/L | '12'13'14'15'16'17'18'19 |
CARBON TETRACHLORIDE worst: 2017 | 0.00072 mg/L within below national p90 | 0.005 mg/L | '17 |
CIS DICHLOROETHYLENE 12 worst: 2015 | 0.0091 mg/L within near national p90 | 0.07 mg/L | '12'13'14'15'16'17'18'19 |
CHROMIUM worst: 2013 | 0.012 mg/L within above national p90 | 0.1 mg/L | '12'13'14 |
DICHLOROETHYLENE 11 worst: 2012 | 0.00058 mg/L within below national p90 | 0.007 mg/L | '12 |
FLUORIDE worst: 2017 | 0.11 mg/L within | 4 mg/L | '12'17 |
BARIUM worst: 2015 | 0.0424 mg/L within below national p90 | 2 mg/L | '14'15'19 |
STYRENE worst: 2014 | 0.0019 mg/L within | 0.1 mg/L | '14'15 |
SELENIUM worst: 2015 | 0.000217 mg/L within | 0.05 mg/L | '14'15 |
ANTIMONY worst: 2015 | 0.000021 mg/L within below national p90 | 0.006 mg/L | '14'15 |
CADMIUM worst: 2015 | 0.000012 mg/L within below national p90 | 0.005 mg/L | '15 |
TOLUENE worst: 2015 | 0.0022 mg/L within | 1 mg/L | '15'18 |
ETHYLBENZENE worst: 2015 | 0.0012 mg/L within | 0.7 mg/L | '15 |
XYLENES TOTAL worst: 2015 | 0.0094 mg/L within | 10 mg/L | '13'15 |
BERYLLIUM worst: 2015 | 0.000002 mg/L within below national p90 | 0.004 mg/L | '15 |
URANIUM worst: 2015 | 0.00108 ug/L within below national p90 | 30 ug/L | '14'15 |
COPPER worst: 2014 | 0.000394 mg/L below national p90 | — | '14'15 |
LEAD worst: 2014 | 0.000051 mg/L | — | '14'15 |
DCAA worst: 2016 | 0.0012 mg/L | — | '16 |
BROMODICHLOROMETHANE worst: 2013 | 0.00308 mg/L | — | '13'15'16'17'18'19 |
BROMOFORM worst: 2013 | 0.00127 mg/L | — | '13 |
CHLOROFORM worst: 2012 | 0.00194 mg/L | — | '12'13'14'15'16'17'18'19 |
DIBROMOCHLOROMETHANE worst: 2013 | 0.00275 mg/L | — | '13'15'16'17'18'19 |
PWSID CA0410002 · 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.
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| IronA naturally occurring metal common in groundwater. | 181.3 UG/LAverageSource water | 300 UG/LMCL | Within the limit |
| Chromium, HexavalentHexavalent chromium ('chromium-6') — the more toxic form of chromium. | 4.009166666666666 UG/LAverageSource water | 10 UG/LMCL | Within the limit |
| AluminumA common element sometimes used as a treatment coagulant. | 221.25 UG/LAverageSource water | 1000 UG/LMCL | Within the limit |
| ManganeseA naturally occurring metal from soil and rock. | 2.9 UG/LAverageSource water | 50 UG/LMCL | Within the limit |
| ZincA naturally occurring metal that can also enter water from corroding pipes. | 4.25 UG/LAverageSource water | 5000 UG/LMCL | Within the limit |
| 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 |
| Thallium | Not detected UG/LHighest single sampleSource water | 2 UG/LMCL | None detected |
| BoronA naturally occurring element from rock and soil. | 114.875 UG/LAverageSource water | None set | Detected — no federal limit |
| CalciumA naturally occurring mineral that contributes to water hardness. | 13.555555555555555 MG/LAverageSource water | None set | Detected — no federal limit |
| MagnesiumA naturally occurring mineral that contributes to water hardness. | 14.290000000000001 MG/LAverageSource water | None set | Detected — no federal limit |
| PotassiumA naturally occurring mineral from rock and soil. | 1.61375 MG/LAverageSource water | None set | Detected — no federal limit |
| SodiumA naturally occurring salt component. | 14.2 MG/LAverageSource water | None set | Detected — no federal limit |
| Strontium | 160 UG/LAverageSource water | None set | Detected — no federal limit |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Total Dissolved SolidsTotal dissolved solids — the combined content of all dissolved minerals and salts. | 213.75 MG/LAverageSource water | 1000 MG/LMCL | Within the limit |
| Specific ConductanceA measure of how well water conducts electricity, which tracks dissolved mineral content. | 306.25 UMHO/CMAverageSource water | 1600 UMHO/CMMCL | Within the limit |
| TurbidityA measure of cloudiness from suspended particles in the water. | 0.2875 NTUAverageSource water | 5 NTUMCL | 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 |
| AlkalinityA measure of the water's capacity to neutralize acids. | 82.16666666666667 MG/LAverageSource water | None set | Detected — no federal limit |
| HardnessA measure of dissolved calcium and magnesium minerals. | 118.75 MG/LAverageSource water | None set | Detected — no federal limit |
| pHA measure of how acidic or basic the water is. | 7.7 PHAverageSource water | None set | Detected — no federal limit |
| TemperatureThe measured temperature of the water sample. | 18.95 CAverageSource water | None set | Detected — no federal limit |
Radionuclides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Combined RadiumCombined radium-226 and radium-228 — naturally occurring radioactive elements. | 0.39791666666666664 PCI/LAverageSource water | 5 PCI/LMCL | Within the limit |
| Gross AlphaGross alpha particle activity — a combined measure of alpha-emitting radioactive substances. | Not detected PCI/LHighest single sampleSource water | 15 PCI/LMCL | None detected |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChlorideA naturally occurring salt compound. | 11.08 MG/LAverageSource water | 500 MG/LMCL | Within the limit |
| SulfateA naturally occurring mineral from rock and soil. | 8.200000000000001 MG/LAverageEntry point | 500 MG/LMCL | Within the limit |
| Cyanide | Not detected UG/LHighest single sampleSource water | 150 UG/LMCL | None detected |
| BromideA naturally occurring salt found in source water. | 0.056 MG/LAverageSource water | None set | Detected — no federal limit |
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| 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 |
| PerchlorateA chemical used in rocket fuel and fireworks that can also form during disinfection. | Not detected UG/LHighest single sampleSource water | 6 UG/LMCL | None detected |
Other
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Carbofuran | Not detected UG/LHighest single sampleSource water | 18 UG/LMCL | None detected |
| Chlordane | Not detected UG/LHighest single sampleSource water | None set | None detected |
| Chlorobenzene | Not detected UG/LHighest single sampleEntry point | 70 UG/LMCL | None detected |
| Dbaa | 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 sampleEntry point | 0.5 UG/LMCL | None detected |
| Dichloropropane 12 | Not detected UG/LHighest single sampleEntry point | 5 UG/LMCL | None detected |
| Dinoseb | Not detected UG/LHighest single sampleSource water | 7 UG/LMCL | None detected |
| Endothall | Not detected UG/LHighest single sampleSource water | 100 UG/LMCL | None detected |
| Endrin | Not detected UG/LHighest single sampleSource water | 2 UG/LMCL | None detected |
| Glyphosate | Not detected UG/LHighest single sampleSource water | 700 UG/LMCL | None detected |
| Heptachlor | Not detected UG/LHighest single sampleSource water | 0.01 UG/LMCL | None detected |
| Heptachlor Epoxide | Not detected UG/LHighest single sampleSource water | 0.01 UG/LMCL | None detected |
| Hexachlorobenzene | Not detected UG/LHighest single sampleSource water | 1 UG/LMCL | None detected |
| Hexachlorocyclopentadiene | Not detected UG/LHighest single sampleSource water | 50 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 |
| Methoxychlor | Not detected UG/LHighest single sampleSource water | 30 UG/LMCL | None detected |
| O Dichlorobenzene | Not detected UG/LHighest single sampleEntry point | 600 UG/LMCL | None detected |
| Oxamyl | Not detected UG/LHighest single sampleSource water | 50 UG/LMCL | None detected |
| P Dichlorobenzene | 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 |
| Tcaa | Not detected UG/LHighest single sampleDistribution | None set | None detected |
| Trans Dichloroethylene 12 | Not detected UG/LHighest single sampleSource water | 10 UG/LMCL | None detected |
| Trichlorobenzene 124 | Not detected UG/LHighest single sampleEntry point | 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 sampleEntry point | 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 sampleEntry point | 0.5 UG/LMCL | None detected |
PFAS ("forever chemicals")
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| 11-Chloroeicosafluoro-3-oxaundecane-1-sulfonic acid (11Cl-PF3OUdS)11-chloroeicosafluoro-3-oxaundecane-1-sulfonic acid, a chlorinated PFAS compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| 4,8-Dioxa-3H-perfluorononanoic acid (ADONA)ADONA, a newer-generation PFAS replacement compound. | Not detected NG/LHighest single sampleEntry point | None set | None detected |
| 4:2 Fluorotelomer sulfonic acid (4:2 FTS)4:2 fluorotelomer sulfonic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleEntry point | None set | None detected |
| 6:2 Fluorotelomer sulfonic acid (6:2 FTS)6:2 fluorotelomer sulfonic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleEntry point | None set | None detected |
| 8:2 Fluorotelomer sulfonic acid (8:2 FTS)8:2 fluorotelomer sulfonic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| 9-Chlorohexadecafluoro-3-oxanonane-1-sulfonic acid (9Cl-PF3ONS)9-chlorohexadecafluoro-3-oxanonane-1-sulfonic acid, a chlorinated PFAS compound. | Not detected NG/LHighest single sampleEntry point | None set | None detected |
| Hexafluoropropylene oxide dimer acidHFPO-DA ('GenX chemicals'), a newer-generation PFAS replacement compound. | Not detected NG/LHighest single sampleEntry point | None set | None detected |
| N-ethyl perfluorooctanesulfonamidoacetic acid (NEtFOSAA)N-ethyl perfluorooctanesulfonamidoacetic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| N-methyl perfluorooctanesulfonamidoacetic acid (NMeFOSAA)N-methyl perfluorooctanesulfonamidoacetic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleEntry point | None set | None detected |
| Perfluoro-3-methoxypropanoic acid (PFMPA)Perfluoro-3-methoxypropanoic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoro-4-methoxybutanoic acid (PFMBA)Perfluoro-4-methoxybutanoic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoro(2-ethoxyethane)sulfonic acid (PFEESA)Perfluoro(2-ethoxyethane)sulfonic acid, a PFAS-related compound. | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluorodecanoic acid (PFDA)Perfluorodecanoic acid, a longer-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleEntry point | None set | None detected |
| Perfluorododecanoic acid (PFDoA)Perfluorododecanoic acid, a longer-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluoroheptanesulfonic acid (PFHpS)Perfluoroheptanesulfonic acid, a PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluorononanoic acidPerfluorononanoic acid, a PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluorotetradecanoic acid (PFTeDA)Perfluorotetradecanoic acid, a longer-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
| Perfluorotridecanoic acid (PFTrDA)Perfluorotridecanoic acid, a longer-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleEntry point | None set | None detected |
| Perfluoroundecanoic acid (PFUnA)Perfluoroundecanoic acid, a longer-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleEntry point | None set | None detected |
| Perfluoroheptanoic acidPerfluoroheptanoic acid, a PFAS 'forever chemical.' | 1.1767123287671233 NG/LAverageSource water | None set | Detected — no federal limit |
| Perfluoropentanesulfonic acid (PFPeS)Perfluoropentanesulfonic acid, a PFAS 'forever chemical.' | 1.1651162790697676 NG/LAverageSource water | None set | Detected — no federal limit |
| PFBAPerfluorobutanoic acid, a shorter-chain PFAS 'forever chemical.' | 1.0255813953488373 NG/LAverageSource water | None set | Detected — no federal limit |
VOCs & pesticides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| 1,2,3-TCP | Not detected UG/LHighest single sampleEntry point | 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 sampleEntry point | 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 |
| 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: Cal-water Service Co.-chico, CA's 2026 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 Cal-water Service Co.-chico, CA's water
+Is Cal-water Service Co.-chico, CA tap water safe to drink in 2026?
Every one of the 124 contaminants measured in Cal-water Service Co.-chico, CA's 2026 Consumer Confidence Report is below its federal limit. "Safe" under the EPA's drinking-water standards is health-based, not aesthetic — but by those standards, no measured contaminant in this report exceeds its enforceable threshold. Individual health concerns (e.g. immunocompromised, infant, pregnancy) may warrant additional filtering regardless of compliance.
+What contaminants are in Cal-water Service Co.-chico, CA tap water?
124 contaminants were measured in Cal-water Service Co.-chico, CA's 2026 Consumer Confidence Report, spanning other, pfas ("forever chemicals"), and metals. 75 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.
+Are any contaminants in Cal-water Service Co.-chico, CA tap water approaching the federal limit?
One contaminant is between 80% and 100% of the federal limit in this report: Carbon Tetrachloride. 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 Cal-water Service Co.-chico, CA's 2026 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 Cal-water Service Co.-chico, 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 2026 report; a new report will replace it once the utility publishes its next annual update.
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