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.
13
health-based violations
27
violations on file
3
still open
| Violation | Type | Status | Period |
|---|---|---|---|
| MCL | Health-based | Archived | 1995-07-01 → 1995-07-31 |
| MCL | Health-based | Archived | 1995-07-01 → 1995-07-31 |
| MCL | Health-based | Resolved | 1991-01-30 → 1995-01-29 |
| MCL | Health-based | Resolved | 1991-01-30 → 1995-01-29 |
| MCL | Health-based | Resolved | 1991-01-30 → 1995-01-29 |
| MCL | Health-based | Resolved | 1991-01-30 → 1995-01-29 |
| MCL | Health-based | Resolved | 1991-01-30 → 1995-01-29 |
| MCL | Health-based | Resolved | 1991-01-30 → 1995-01-29 |
| MCL | Health-based | Resolved | 1991-01-30 → 1995-01-29 |
| MCL | Health-based | Resolved | 1991-01-30 → 1995-01-29 |
PFAS detected
PFAS are industrial “forever chemicals”. These are the EPA's latest
nationwide test results (2023–2025).
| Contaminant | Max | Detection rate | Period |
|---|---|---|---|
| PFBS | 0.0043 µg/L | 2/9 | 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 |
|---|---|---|---|---|
| Copper | 217 µg/L 17% of the EPA limit 1300 µg/L
worst single sample: 252 µg/L | 47/60 | SYR4 | 2014–2017 |
| TTHM | 31.05 µg/L 39% of the EPA limit 80 µg/L
worst single sample: 50 µg/L | 35/35 | SYR4 | 2012–2019 |
| Bromodichloromethane | 7.0465 µg/L No EPA limit set
worst single sample: 8.37 µg/L | 34/35 | SYR4 | 2012–2019 |
| Chloroform | 23.8 µg/L No EPA limit set
worst single sample: 42.5 µg/L | 33/35 | SYR4 | 2012–2019 |
| Dibromochloromethane | 9.172 µg/L No EPA limit set
worst single sample: 9.63 µg/L | 33/35 | SYR4 | 2012–2019 |
| Total Haloacetic Acids (HAA5) | 11.275 µg/L 19% of the EPA limit 60 µg/L
worst single sample: 24.3 µg/L | 31/35 | SYR4 | 2012–2019 |
| Nitrate | 613.5 µg/L 6.1% of the EPA limit 10000 µg/L
worst single sample: 690 µg/L | 30/98 | SYR4 | 2012–2019 |
| Fluoride | 1106 µg/L 28% of the EPA limit 4000 µg/L
worst single sample: 1200 µg/L | 25/25 | SYR4 | 2012–2019 |
| Lead | 18.36 µg/L 122% of the EPA limit, at the 95th percentile of samples — 15 µg/L
worst single sample: 140 µg/L | 25/60 | SYR4 | 2014–2017 |
| Bromoform | 4.163 µg/L No EPA limit set
worst single sample: 5.96 µg/L | 22/35 | SYR4 | 2012–2019 |
| Dichloroacetic Acid | 4.8355 µg/L No EPA limit set
worst single sample: 19.2 µg/L | 22/35 | SYR4 | 2012–2019 |
| Lead | 0.0033 mg/L 22% of the EPA limit 0.0150 mg/L | 20/20 | LCR | 2026 |
| Monobromoacetic Acid | 6.019 µg/L No EPA limit set
worst single sample: 7.52 µg/L | 20/35 | SYR4 | 2012–2019 |
| Barium | 1190.5 µg/L 60% of the EPA limit 2000 µg/L
worst single sample: 1420 µg/L | 18/18 | SYR4 | 2012–2018 |
| Trichloroacetic Acid | 2.295 µg/L No EPA limit set
worst single sample: 4.08 µg/L | 15/35 | SYR4 | 2012–2019 |
| Combined Radium (-226 And -228) | 4.677 pCi/L 94% of the EPA limit 5 pCi/L
worst single sample: 5.26 pCi/L | 12/13 | SYR4 | 2012–2019 |
| Nitrate-Nitrite | 480.3 µg/L 4.8% of the EPA limit 10000 µg/L
worst single sample: 495 µg/L | 8/20 | SYR4 | 2012–2018 |
| Dibromoacetic Acid | 4.0625 µg/L No EPA limit set
worst single sample: 4.71 µg/L | 6/35 | SYR4 | 2012–2019 |
| Lithium | 28.6 µg/L No EPA limit set | 6/9 | UCMR-5 | 2025 |
| Arsenic | 0.8115 µg/L 8.1% of the EPA limit 10 µg/L
worst single sample: 0.8210 µg/L | 4/18 | SYR4 | 2012–2018 |
| Chromium | 8 µg/L 8% of the EPA limit 100 µg/L | 4/18 | SYR4 | 2012–2018 |
| Selenium | 5.2 µg/L 10% of the EPA limit 50 µg/L
worst single sample: 5.5 µg/L | 3/18 | SYR4 | 2012–2018 |
| Benzo(A)Pyrene | 0.1470 µg/L 73% of the EPA limit 0.2000 µg/L | 1/43 | SYR4 | 2012–2019 |
| Carbon Tetrachloride | 1.5 µg/L 30% of the EPA limit 5 µg/L | 1/19 | SYR4 | 2014–2019 |
| Nitrite | 12 µg/L 1.2% of the EPA limit 1000 µg/L | 1/47 | SYR4 | 2012–2018 |
82 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,4,5-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalAtrazineBhc-GammaBenzeneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbofuranChlordaneDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebDiquatEthylene DibromideEndothallEndrinEthylbenzeneHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonochloroacetic AcidNetfosaaNfdhaNmefosaaOxamylPfbaPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene
Utility contact
Frequently asked questions about St Charles
Is St Charles tap water safe to drink?
EPA monitoring detected 26 contaminants in St Charles'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 St Charles's water?
EPA monitoring detected Copper, TTHM, Bromodichloromethane, Chloroform, Dibromochloromethane, and others. The full list with the level and data source for each is above.
How many people does St Charles serve?
St Charles reports serving 33,103 people in Illinois, per its EPA record.
Has St Charles had any water quality violations?
The EPA has 27 violations on file for St Charles, of which 13 are health-based (a contaminant limit or required treatment was breached) and 3 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.