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 |
|---|---|---|---|
| MCL | Health-based | Archived | 2025-04-01 → 2025-06-30 |
| MCL | Health-based | Archived | 2025-04-01 → 2025-06-30 |
| MCL | Health-based | Archived | 2025-04-01 → 2025-06-30 |
| MCL | Health-based | Archived | 2025-01-01 → 2025-03-31 |
| MCL | Health-based | Archived | 2025-01-01 → 2025-03-31 |
| TT | Health-based | Resolved | 2024-10-17 |
| TT | Health-based | Resolved | 2024-10-17 |
| TT | Health-based | Resolved | 2024-10-17 |
| TT | Health-based | Resolved | 2024-10-17 |
| TT | Health-based | Resolved | 2014-01-01 |
PFAS detected
Other contaminants detected
| Contaminant | Level vs EPA limit | Detection rate | Source | Period |
|---|---|---|---|---|
| Nitrate | 3900 µg/L 39% of the EPA limit 10000 µg/L
worst single sample: 4650 µg/L | 86/96 | SYR4 | 2012–2019 |
| Combined Uranium | 31 µg/L 103% of the EPA limit, at the 95th percentile of samples — 30 µg/L
worst single sample: 35 µg/L | 44/44 | SYR4 | 2013–2019 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L | 17/17 | LCR | 2023 |
| Trichloroethylene | 2.265 µg/L 45% of the EPA limit 5 µg/L
worst single sample: 2.31 µg/L | 16/23 | SYR4 | 2012–2019 |
| Gross Alpha, Excl. Radon And U | 16.095 pCi/L 107% of the EPA limit, at the 95th percentile of samples — 15 pCi/L
worst single sample: 23.7 pCi/L | 14/15 | SYR4 | 2017–2019 |
| Lithium | 24 µg/L No EPA limit set | 8/8 | UCMR-5 | 2023 |
| Nitrate-Nitrite | 3580 µg/L 36% of the EPA limit 10000 µg/L
worst single sample: 4000 µg/L | 5/5 | SYR4 | 2019 |
| Fluoride | 381 µg/L 9.5% of the EPA limit 4000 µg/L
worst single sample: 390 µg/L | 4/4 | SYR4 | 2019 |
| Arsenic | 3.49 µg/L 35% of the EPA limit 10 µg/L
worst single sample: 3.5 µg/L | 3/4 | SYR4 | 2019 |
| Barium | 153 µg/L 7.7% of the EPA limit 2000 µg/L
worst single sample: 160 µg/L | 3/4 | SYR4 | 2019 |
| Combined Radium (-226 And -228) | 0.7018 pCi/L 14% of the EPA limit 5 pCi/L
worst single sample: 0.7020 pCi/L | 2/4 | SYR4 | 2016 |
80 contaminants tested, none detected
Utility contact
Frequently asked questions about Capitol Water Corp
Is Capitol Water Corp tap water safe to drink?
EPA monitoring detected 18 contaminants in Capitol Water Corp'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 Capitol Water Corp's water?
EPA monitoring detected Nitrate, Combined Uranium, Lead, Trichloroethylene, Gross Alpha, Excl. Radon And U, and others. The full list with the level and data source for each is above.
How many people does Capitol Water Corp serve?
Capitol Water Corp reports serving 9,000 people in Idaho, per its EPA record.
Has Capitol Water Corp had any water quality violations?
The EPA has 343 violations on file for Capitol Water Corp, of which 14 are health-based (a contaminant limit or required treatment was breached) and 2 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.