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.
| Violation | Type | Status | Period |
|---|---|---|---|
| TT | Health-based | Resolved | 1993-06-01 → 1993-06-30 |
| TT | Health-based | Resolved | 1993-06-01 → 1993-06-30 |
| TT | Health-based | Resolved | 1993-06-01 → 1993-06-30 |
| TT | Health-based | Resolved | 1993-06-01 → 1993-06-30 |
PFAS detected
Other contaminants detected
| Contaminant | Level vs EPA limit | Detection rate | Source | Period |
|---|---|---|---|---|
| Nitrate | 12000 µg/L 120% of the EPA limit, at the 95th percentile of samples — 10000 µg/L
worst single sample: 14000 µg/L | 1814/1956 | SYR4 | 2012–2019 |
| TTHM | 71.5 µg/L 89% of the EPA limit 80 µg/L
worst single sample: 77 µg/L | 171/201 | SYR4 | 2012–2019 |
| Chloroform | 15 µg/L No EPA limit set
worst single sample: 30 µg/L | 168/214 | SYR4 | 2012–2019 |
| Bromodichloromethane | 20.15 µg/L No EPA limit set
worst single sample: 23 µg/L | 158/214 | SYR4 | 2012–2019 |
| Dibromochloromethane | 25 µg/L No EPA limit set
worst single sample: 28 µg/L | 158/214 | SYR4 | 2012–2019 |
| Bromoform | 27.5 µg/L No EPA limit set
worst single sample: 29 µg/L | 151/214 | SYR4 | 2012–2019 |
| 1,2-DIBROMO-3-CHLOROPROPANE | 0.1200 µg/L 60% of the EPA limit 0.2000 µg/L
worst single sample: 0.1600 µg/L | 135/186 | SYR4 | 2012–2019 |
| Total Haloacetic Acids (HAA5) | 31.5 µg/L 53% of the EPA limit 60 µg/L
worst single sample: 43 µg/L | 116/201 | SYR4 | 2012–2019 |
| Dibromoacetic Acid | 10.805 µg/L No EPA limit set
worst single sample: 13 µg/L | 104/201 | SYR4 | 2012–2019 |
| Trichloroacetic Acid | 4.205 µg/L No EPA limit set
worst single sample: 5.6 µg/L | 100/201 | SYR4 | 2012–2019 |
| Fluoride | 400 µg/L 10% of the EPA limit 4000 µg/L
worst single sample: 500 µg/L | 92/93 | SYR4 | 2012–2019 |
| Chromium | 7.45 µg/L 7.5% of the EPA limit 100 µg/L
worst single sample: 8.8 µg/L | 86/87 | SYR4 | 2012–2019 |
| Dichloroacetic Acid | 5.405 µg/L No EPA limit set
worst single sample: 7.8 µg/L | 80/201 | SYR4 | 2012–2019 |
| Monobromoacetic Acid | 7.16 µg/L No EPA limit set
worst single sample: 7.8 µg/L | 69/201 | SYR4 | 2012–2019 |
| Monochloroacetic Acid | 27 µg/L No EPA limit set
worst single sample: 31 µg/L | 36/201 | SYR4 | 2012–2019 |
| Barium | 139.5 µg/L 7% of the EPA limit 2000 µg/L
worst single sample: 140 µg/L | 22/87 | SYR4 | 2012–2019 |
| Lead | 0.00060 mg/L 4% of the EPA limit 0.0150 mg/L | 21/21 | LCR | 2024 |
| Nitrite | 4525 µg/L 453% of the EPA limit, at the 95th percentile of samples — 1000 µg/L
worst single sample: 4900 µg/L | 16/87 | SYR4 | 2012–2019 |
| Nitrate-Nitrite | 9840 µg/L 98% of the EPA limit 10000 µg/L
worst single sample: 12000 µg/L | 13/13 | SYR4 | 2017 |
| Arsenic | 2.39 µg/L 24% of the EPA limit 10 µg/L
worst single sample: 2.4 µg/L | 3/87 | SYR4 | 2012–2019 |
| Ethylene Dibromide | 0.0210 µg/L 42% of the EPA limit 0.0500 µg/L | 1/127 | SYR4 | 2012–2019 |
83 contaminants tested, none detected
Utility contact
Frequently asked questions about Ontario Municipal Utilities Company
Is Ontario Municipal Utilities Company tap water safe to drink?
EPA monitoring detected 27 contaminants in Ontario Municipal Utilities Company'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 Ontario Municipal Utilities Company's water?
EPA monitoring detected Nitrate, TTHM, Chloroform, Bromodichloromethane, Dibromochloromethane, and others. The full list with the level and data source for each is above.
How many people does Ontario Municipal Utilities Company serve?
Ontario Municipal Utilities Company reports serving 185,010 people in California, per its EPA record.
Has Ontario Municipal Utilities Company had any water quality violations?
The EPA has 4 violations on file for Ontario Municipal Utilities Company, of which 4 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.