Compliance record
Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.
15
health-based violations
97
violations on file
0
still open
| Violation | Type | Status | Period |
|---|---|---|---|
| MCL | Health-based | Resolved | 2001-06-01 → 2001-06-30 |
| MCL | Health-based | Resolved | 2001-06-01 → 2001-06-30 |
| TT | Health-based | Resolved | 1993-07-01 → 1993-07-31 |
| TT | Health-based | Resolved | 1993-07-01 → 1993-07-31 |
| MCL | Health-based | Resolved | 1993-01-01 → 1993-01-31 |
| MCL | Health-based | Resolved | 1993-01-01 → 1993-01-31 |
| MCL | Health-based | Resolved | 1993-01-01 → 1993-01-31 |
| MCL | Health-based | Archived | 1980-10-01 → 1980-12-31 |
| MCL | Health-based | Archived | 1980-08-30 → 1980-10-29 |
| MCL | Health-based | Archived | 1980-06-30 → 1980-07-29 |
PFAS detected
PFAS are industrial “forever chemicals”. These are the EPA's latest
nationwide test results (2023–2025).
Other contaminants detected
Each bar shows the measured level as a share of the EPA limit: green is
well under, amber is close to it, red is over. For lead and copper the
limit applies to exactly the 90th-percentile figure shown, so red there
means a real exceedance. For everything else the limit applies to a
running annual average while the figure is the 95th percentile of this
system's samples — over 100% is worth reading, but is not by itself a
violation. Where a single sample came in higher than that percentile, it
is noted under the bar. Formal violations are listed separately.
| Contaminant | Level vs EPA limit | Detection rate | Source | Period |
|---|---|---|---|---|
| Nitrate | 17000 µg/L 170% of the EPA limit, at the 95th percentile of samples — 10000 µg/L
worst single sample: 58760 µg/L | 15170/16616 | SYR4 | 2012–2019 |
| Fluoride | 820 µg/L 21% of the EPA limit 4000 µg/L
worst single sample: 4600 µg/L | 921/1192 | SYR4 | 2012–2019 |
| TTHM | 36 µg/L 45% of the EPA limit 80 µg/L
worst single sample: 42 µg/L | 236/320 | SYR4 | 2012–2019 |
| Dibromochloromethane | 11 µg/L No EPA limit set
worst single sample: 15 µg/L | 222/335 | SYR4 | 2012–2019 |
| Bromodichloromethane | 10 µg/L No EPA limit set
worst single sample: 12 µg/L | 216/334 | SYR4 | 2012–2019 |
| Bromoform | 11.55 µg/L No EPA limit set
worst single sample: 17 µg/L | 210/334 | SYR4 | 2012–2019 |
| Chloroform | 11 µg/L No EPA limit set
worst single sample: 17 µg/L | 209/331 | SYR4 | 2012–2019 |
| Total Haloacetic Acids (HAA5) | 14 µg/L 23% of the EPA limit 60 µg/L
worst single sample: 26 µg/L | 190/283 | SYR4 | 2012–2019 |
| Dibromoacetic Acid | 4.3 µg/L No EPA limit set
worst single sample: 6.4 µg/L | 178/283 | SYR4 | 2012–2019 |
| Dichloroacetic Acid | 5.765 µg/L No EPA limit set
worst single sample: 15 µg/L | 168/283 | SYR4 | 2012–2019 |
| Trichloroacetic Acid | 4.5 µg/L No EPA limit set
worst single sample: 7.2 µg/L | 130/283 | SYR4 | 2012–2019 |
| Trichloroethylene | 1.765 µg/L 35% of the EPA limit 5 µg/L
worst single sample: 1.9 µg/L | 88/268 | SYR4 | 2012–2019 |
| Combined Uranium | 30.0235 µg/L 100% of the EPA limit, at the 95th percentile of samples — 30 µg/L
worst single sample: 58.11 µg/L | 78/99 | SYR4 | 2012–2019 |
| Arsenic | 14.1 µg/L 141% of the EPA limit, at the 95th percentile of samples — 10 µg/L
worst single sample: 18 µg/L | 70/200 | SYR4 | 2012–2019 |
| Barium | 364.5 µg/L 18% of the EPA limit 2000 µg/L
worst single sample: 460 µg/L | 52/200 | SYR4 | 2012–2019 |
| Monochloroacetic Acid | 6.985 µg/L No EPA limit set
worst single sample: 8.1 µg/L | 34/283 | SYR4 | 2012–2019 |
| Selenium | 29.3 µg/L 59% of the EPA limit 50 µg/L
worst single sample: 35 µg/L | 28/200 | SYR4 | 2012–2019 |
| Lead | 0.0037 mg/L 25% of the EPA limit 0.0150 mg/L | 25/25 | LCR | 2023 |
| Tetrachloroethylene | 0.9460 µg/L 19% of the EPA limit 5 µg/L
worst single sample: 1 µg/L | 24/234 | SYR4 | 2012–2019 |
| Lithium | 55.1 µg/L No EPA limit set | 24/54 | UCMR-5 | 2024 |
| 1,2-DIBROMO-3-CHLOROPROPANE | 0.0420 µg/L 21% of the EPA limit 0.2000 µg/L
worst single sample: 0.0500 µg/L | 21/251 | SYR4 | 2012–2019 |
| Monobromoacetic Acid | 1.845 µg/L No EPA limit set
worst single sample: 2.1 µg/L | 18/283 | SYR4 | 2012–2019 |
| Chromium | 3.8 µg/L 3.8% of the EPA limit 100 µg/L
worst single sample: 4.9 µg/L | 11/200 | SYR4 | 2012–2019 |
| Nitrate-Nitrite | 15600 µg/L 156% of the EPA limit, at the 95th percentile of samples — 10000 µg/L
worst single sample: 16000 µg/L | 5/6 | SYR4 | 2015–2019 |
83 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,3,7,8-TCDD2,4,5-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalAsbestosAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCopperCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebDiquatEthylene DibromideEndothallEndrinEthylbenzeneGlyphosateHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoLeadMercuryMethoxychlorNetfosaaNfdhaNmefosaaNitriteOxamylPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfmbaPfmpaPFNAPFOAPFOSPfpesPftaPftrdaPfunaPentachlorophenolPicloramSimazineStyreneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene
Utility contact
Frequently asked questions about Corona, City of
Is Corona, City of tap water safe to drink?
EPA monitoring detected 28 contaminants in Corona, City of's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.
What contaminants were detected in Corona, City of's water?
EPA monitoring detected Nitrate, Fluoride, TTHM, Dibromochloromethane, Bromodichloromethane, and others. The full list with the level and data source for each is above.
How many people does Corona, City of serve?
Corona, City of reports serving 168,575 people in California, per its EPA record.
Has Corona, City of had any water quality violations?
The EPA has 97 violations on file for Corona, City of, of which 15 are health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.
Where does this data come from?
Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.