Drinking water quality · 2023
· Verified
What's in City of Clovis, CA tap water
111 contaminants were measured in the City of Clovis, CA water system's 2023 annual report. Each is shown below against its federal limit — 2 sit at or above that limit.
- Reporting year
- 2023
- Contaminants measured
- 111
- Over federal limit
- 2
- Approaching the limit
- 1
- Worst contaminant
- PFOS
- Service area
- CA
10.3× the limit
state-level CCR
At or above the federal limit
Approaching the limit (≥ 80%)
PFAS — EPA UCMR5 (2023–2025)
2 PFAS compounds above EPA limits in City of Clovis, 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 (10.3×)Measured 41 ng/LEPA limit 4 ng/LSample year 2023Samples 8 detect / 76
2.1× the national p90 (19.900000000000006 ng/L across detecting U.S. systems)
PFOA (Perfluorooctanoic acid)
● Over EPA limit (4.5×)Measured 18 ng/LEPA limit 4 ng/LSample year 2023Samples 9 detect / 76
above national p90 (13.649999999999999 ng/L across detecting U.S. systems)
PFHxS (Perfluorohexane sulfonic acid)
● Approaching limit (88%)Measured 8.8 ng/LEPA limit 10 ng/LSample year 2023Samples 4 detect / 76
near national p90 (12.049999999999997 ng/L across detecting U.S. systems)
PFNA (Perfluorononanoic acid)
● Below limitMeasured 6.9 ng/LEPA limit 10 ng/LSample year 2023Samples 2 detect / 76
below national p90 (25.08 ng/L across detecting U.S. systems)
PFDA
● Detected (no federal limit)Measured 0.0031 µg/LSample year 2023Samples 2 detect / 76
below national p90 (0.00995 µg/L across detecting U.S. systems)
PFHpA
● Detected (no federal limit)Measured 5.7 ng/LSample year 2023Samples 2 detect / 76
near national p90 (9.309999999999999 ng/L across detecting U.S. systems)
PFBS
● Detected (no federal limit)Measured 7.9 ng/LSample year 2023Samples 10 detect / 76
near national p90 (13.909999999999979 ng/L across detecting U.S. systems)
PFPeA
● Detected (no federal limit)Measured 8.4 ng/LSample year 2023Samples 3 detect / 76
near national p90 (15.95999999999999 ng/L across detecting U.S. systems)
PFBA
● Detected (no federal limit)Measured 6.1 ng/LSample year 2023Samples 1 detect / 76
below national p90 (18 ng/L across detecting U.S. systems)
PFHxA
● Detected (no federal limit)Measured 8 ng/LSample year 2023Samples 6 detect / 76
near national p90 (12.190000000000003 ng/L across detecting U.S. systems)
PWSID CA1010003 · 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
City of Clovis, CA's drinking water comes from ground water, drawn from 38 sources.
Source
38ground water
- WELL 40 - RAW STBY2025
- WELL 037 - RAW
- WELL 17 - RAW
- WELL 12 - BEFORE_GAC-DBCP&TCP
- + 34 more
Treatment
38treatment plants
- WELL 41 - TRT CL
- WELL 05A - TRT CL
- WELL 14 - CL2
- + 35 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 City of Clovis, 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) |
|---|---|---|---|
DBCP worst: 2012 | 0.00057 mg/L 2.8× above national p90 | 0.0002 mg/L | '12'13'14'15'16'17'18'19 |
NITRATE worst: 2016 | 13 mg/L 1.3× | 10 mg/L | '12'13'14'15'16'17'18'19 |
TTHM worst: 2018 | 0.079 mg/L 99% | 0.08 mg/L | '12'13'14'15'16'17'18'19 |
NITRATE NITRITE worst: 2019 | 9.8 mg/L 98% | 10 mg/L | '16'17'18'19 |
HAA5 worst: 2016 | 0.045 mg/L within | 0.06 mg/L | '12'13'14'15'16'17'18'19 |
SELENIUM worst: 2014 | 0.024 mg/L within | 0.05 mg/L | '14 |
EDB worst: 2017 | 0.00002 mg/L within | 0.00005 mg/L | '17 |
ARSENIC worst: 2018 | 0.0039 mg/L within below national p90 | 0.01 mg/L | '14'15'16'17'18'19 |
BARIUM worst: 2014 | 0.17 mg/L within near national p90 | 2 mg/L | '14'15'16'17'18'19 |
FLUORIDE worst: 2017 | 0.24 mg/L within | 4 mg/L | '12'14'15'16'17'18'19 |
MCAA worst: 2013 | 0.0066 mg/L | — | '13'14'16'17'18'19 |
TCAA worst: 2012 | 0.0061 mg/L | — | '12'13'14'15'16'17'18'19 |
COPPER worst: 2018 | 0.074 mg/L below national p90 | — | '18 |
LEAD worst: 2018 | 0.0059 mg/L | — | '18 |
DBAA worst: 2013 | 0.0015 mg/L | — | '13'15'16'17'19 |
DCAA worst: 2012 | 0.014 mg/L | — | '12'13'14'15'16'17'18'19 |
MBAA worst: 2014 | 0.001 mg/L | — | '14 |
BROMODICHLOROMETHANE worst: 2012 | 0.007 mg/L | — | '12'13'14'15'16'17'18'19 |
BROMOFORM worst: 2016 | 0.0014 mg/L | — | '16'17 |
CHLOROFORM worst: 2012 | 0.035 mg/L | — | '12'13'14'15'16'17'18'19 |
DIBROMOCHLOROMETHANE worst: 2012 | 0.0024 mg/L | — | '12'13'14'15'16'17'18'19 |
PWSID CA1010003 · 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.
VOCs & pesticides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| 1,2,3-TCP | 0.0037982456140350875 UG/LAverageSource water | 0.005 UG/LMCL | Within the limit |
| 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 |
| Dalapon | Not detected UG/LHighest single sampleSource water | 200 UG/LMCL | 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 |
| Toluene | Not detected UG/LHighest single sampleSource water | 150 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 |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| OdorA measure of detectable smell in the water. | 1.3 TONAverageEntry point | 3 TONMCL | Within the limit |
| Total Dissolved SolidsTotal dissolved solids — the combined content of all dissolved minerals and salts. | 236.35 MG/LAverageSource water | 1000 MG/LMCL | Within the limit |
| Specific ConductanceA measure of how well water conducts electricity, which tracks dissolved mineral content. | 336.2926829268293 UMHO/CMAverageSource water | 1600 UMHO/CMMCL | Within the limit |
| ColorA measure of visible tint in the water. | 3 UNITSAverageSource water | 15 UNITSMCL | Within the limit |
| TurbidityA measure of cloudiness from suspended particles in the water. | 0.46699999999999997 NTUAverageSource water | 5 NTUMCL | Within the limit |
| AlkalinityA measure of the water's capacity to neutralize acids. | 91.88333333333334 MG/LAverageSource water | None set | Detected — no federal limit |
| HardnessA measure of dissolved calcium and magnesium minerals. | 122.2675 MG/LAverageSource water | None set | Detected — no federal limit |
| pHA measure of how acidic or basic the water is. | 7.8225 PHAverageSource water | None set | Detected — no federal limit |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ManganeseA naturally occurring metal from soil and rock. | 20 UG/LAverageSource water | 50 UG/LMCL | Within the limit |
| IronA naturally occurring metal common in groundwater. | 80.73809523809524 UG/LAverageSource water | 300 UG/LMCL | Within the limit |
| AluminumA common element sometimes used as a treatment coagulant. | 26.9 UG/LAverageSource water | 1000 UG/LMCL | Within the limit |
| Antimony | Not detected UG/LHighest single sampleSource water | 6 UG/LMCL | None detected |
| Beryllium | Not detected UG/LHighest single sampleSource water | 4 UG/LMCL | None detected |
| BoronA naturally occurring element from rock and soil. | Not detected UG/LHighest single sampleSource water | None set | None detected |
| Cadmium | Not detected UG/LHighest single sampleEntry point | 5 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 |
| Thallium | Not detected UG/LHighest single sampleSource water | 2 UG/LMCL | None detected |
| ZincA naturally occurring metal that can also enter water from corroding pipes. | Not detected UG/LHighest single sampleSource water | 5000 UG/LMCL | None detected |
| CalciumA naturally occurring mineral that contributes to water hardness. | 13.59875 MG/LAverageSource water | None set | Detected — no federal limit |
| MagnesiumA naturally occurring mineral that contributes to water hardness. | 14.0675 MG/LAverageSource water | None set | Detected — no federal limit |
| PotassiumA naturally occurring mineral from rock and soil. | 2.17 MG/LAverageSource water | None set | Detected — no federal limit |
| SodiumA naturally occurring salt component. | 21.2875 MG/LAverageSource water | None set | Detected — no federal limit |
Radionuclides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Gross AlphaGross alpha particle activity — a combined measure of alpha-emitting radioactive substances. | 2.266625 PCI/LAverageSource water | 15 PCI/LMCL | Within the limit |
| Combined RadiumCombined radium-226 and radium-228 — naturally occurring radioactive elements. | 0.24175 PCI/LAverageSource water | None set | Detected — no federal limit |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| NitriteA compound from fertilizer runoff, sewage, and erosion of natural deposits. | 0.025750000000000002 MG/LAverageSource water | 1 MG/LMCL | Within the limit |
| SulfateA naturally occurring mineral from rock and soil. | 10.71175 MG/LAverageSource water | 500 MG/LMCL | Within the limit |
| ChlorideA naturally occurring salt compound. | 8.915000000000001 MG/LAverageSource water | 500 MG/LMCL | Within the limit |
| Cyanide | 2.5825 UG/LAverageSource water | 150 UG/LMCL | Within the limit |
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| 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 |
|---|---|---|---|
| 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 |
| Chromium | Not detected UG/LHighest single sampleSource water | 50 UG/LMCL | None detected |
| Cis Dichloroethylene 12 | Not detected UG/LHighest single sampleSource water | 6 UG/LMCL | 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 |
| 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 |
| 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 |
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 sampleSource water | 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 sampleSource water | 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 sampleSource water | 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 sampleSource water | None set | None detected |
| Hexafluoropropylene oxide dimer acidHFPO-DA ('GenX chemicals'), a newer-generation PFAS replacement compound. | Not detected NG/LHighest single sampleSource water | 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 sampleSource water | 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 |
| 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 |
| Perfluoropentanesulfonic acid (PFPeS)Perfluoropentanesulfonic 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 sampleSource water | None set | None detected |
| Perfluoroundecanoic acid (PFUnA)Perfluoroundecanoic acid, a longer-chain PFAS 'forever chemical.' | Not detected NG/LHighest single sampleSource water | None set | None detected |
Source: City of Clovis, CA's 2023 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 City of Clovis, CA's water
+Is City of Clovis, CA tap water safe to drink in 2023?
The 2023 Consumer Confidence Report for the City of Clovis, CA water utility lists 2 contaminants at or above the federal limit: PFOS and PFOA. 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 City of Clovis, CA tap water?
111 contaminants were measured in City of Clovis, CA's 2023 Consumer Confidence Report, spanning other, pfas ("forever chemicals"), and metals. 67 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 City of Clovis, CA tap water?
2 contaminants in City of Clovis, CA's 2023 report sit at or above the federal limit: PFOS (10.3× the limit); PFOA (4.5× 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 City of Clovis, CA tap water?
The contaminant with the highest measured value relative to its federal limit in the 2023 report is PFOS, at 10.3× the federal threshold. It belongs to the pfas ("forever chemicals") family of contaminants.
+Are any contaminants in City of Clovis, CA tap water approaching the federal limit?
One contaminant is between 80% and 100% of the federal limit in this report: Perfluorohexanesulfonic acid. 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 City of Clovis, CA's 2023 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 City of Clovis, 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 2023 report; a new report will replace it once the utility publishes its next annual update.
More water systems in CA
City of ClovisCity of ClovisClovisCws - VisaliaCws - VisaliaCws - VisaliaVisaliaBakersfieldBakersfield, City ofBakersfield, City ofBakersfield, City ofTracyTracy, City ofTracy, City ofTracy, City ofCity of StocktonCity of StocktonCity of StocktonStocktonCwsc SalinasCwsc SalinasCwsc SalinasCwsc SalinasCity of San Jose - Evg/edv/coyAll water systems →