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 | Resolved | 2014-07-01 → 2014-09-30 |
| MCL | Health-based | Resolved | 2014-07-01 → 2014-09-30 |
| MCL | Health-based | Resolved | 2014-07-01 → 2014-09-30 |
| MCL | Health-based | Resolved | 2014-07-01 → 2014-09-30 |
| TT | Health-based | Resolved | 2008-01-01 → 2008-02-01 |
| TT | Health-based | Resolved | 2008-01-01 → 2008-02-01 |
| TT | Health-based | Resolved | 2008-01-01 → 2008-02-01 |
| TT | Health-based | Resolved | 2008-01-01 → 2008-02-01 |
| TT | Health-based | Resolved | 2007-03-01 → 2007-04-01 |
| TT | Health-based | Resolved | 2007-03-01 → 2007-04-01 |
PFAS detected
Other contaminants detected
| Contaminant | Level vs EPA limit | Detection rate | Source | Period |
|---|---|---|---|---|
| Copper | 205.8 µg/L 16% of the EPA limit 1300 µg/L
worst single sample: 362 µg/L | 199/201 | SYR4 | 2016–2019 |
| Nitrate | 6950 µg/L 70% of the EPA limit 10000 µg/L
worst single sample: 7500 µg/L | 106/116 | SYR4 | 2014–2019 |
| Chloroform | 84.4 µg/L No EPA limit set
worst single sample: 94 µg/L | 97/129 | SYR4 | 2014–2019 |
| TTHM | 98 µg/L 123% of the EPA limit, at the 95th percentile of samples — 80 µg/L
worst single sample: 109 µg/L | 91/99 | SYR4 | 2014–2019 |
| Bromodichloromethane | 13 µg/L No EPA limit set
worst single sample: 14 µg/L | 90/129 | SYR4 | 2014–2019 |
| Total Haloacetic Acids (HAA5) | 65.3 µg/L 109% of the EPA limit, at the 95th percentile of samples — 60 µg/L
worst single sample: 75 µg/L | 88/88 | SYR4 | 2014–2019 |
| Trichloroacetic Acid | 40.5742 µg/L No EPA limit set
worst single sample: 46 µg/L | 84/84 | SYR4 | 2014–2019 |
| Dichloroacetic Acid | 23 µg/L No EPA limit set
worst single sample: 28.072 µg/L | 82/84 | SYR4 | 2014–2019 |
| Dibromochloromethane | 2.12 µg/L No EPA limit set
worst single sample: 2.8 µg/L | 80/129 | SYR4 | 2014–2019 |
| Lead | 46.9225 µg/L 313% of the EPA limit, at the 95th percentile of samples — 15 µg/L
worst single sample: 143.986 µg/L | 30/187 | SYR4 | 2016–2019 |
| Nitrate-Nitrite | 6780 µg/L 68% of the EPA limit 10000 µg/L
worst single sample: 7500 µg/L | 27/29 | SYR4 | 2014–2016 |
| Lead | 0.0 mg/L 0% of the EPA limit 0.0150 mg/L | 18/18 | LCR | 2024 |
| Barium | 20.775 µg/L 1% of the EPA limit 2000 µg/L
worst single sample: 22.4 µg/L | 14/15 | SYR4 | 2016–2019 |
| Chromium | 9.01 µg/L 9% of the EPA limit 100 µg/L
worst single sample: 10.3 µg/L | 4/15 | SYR4 | 2016–2019 |
| Combined Uranium | 1.525 µg/L 5.1% of the EPA limit 30 µg/L
worst single sample: 1.6 µg/L | 4/12 | SYR4 | 2016–2019 |
| Gross Alpha, Excl. Radon And U | 1 pCi/L 6.7% of the EPA limit 15 pCi/L | 4/10 | SYR4 | 2016–2018 |
| Monochloroacetic Acid | 9.68415 µg/L No EPA limit set
worst single sample: 10.734 µg/L | 4/84 | SYR4 | 2014–2019 |
| Arsenic | 1.495 µg/L 15% of the EPA limit 10 µg/L
worst single sample: 1.5 µg/L | 2/15 | SYR4 | 2016–2019 |
| Combined Radium (-226 And -228) | 1.998 pCi/L 40% of the EPA limit 5 pCi/L
worst single sample: 2 pCi/L | 2/11 | SYR4 | 2016–2018 |
| Fluoride | 554 µg/L 14% of the EPA limit 4000 µg/L
worst single sample: 560 µg/L | 2/15 | SYR4 | 2016–2019 |
| Lithium | 10 µg/L No EPA limit set | 2/18 | UCMR-5 | 2024 |
80 contaminants tested, none detected
Utility contact
Frequently asked questions about Portsmouth Water Works
Is Portsmouth Water Works tap water safe to drink?
EPA monitoring detected 29 contaminants in Portsmouth Water Works'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 Portsmouth Water Works's water?
EPA monitoring detected Copper, Nitrate, Chloroform, TTHM, Bromodichloromethane, and others. The full list with the level and data source for each is above.
How many people does Portsmouth Water Works serve?
Portsmouth Water Works reports serving 33,000 people in New Hampshire, per its EPA record.
Has Portsmouth Water Works had any water quality violations?
The EPA has 43 violations on file for Portsmouth Water Works, of which 43 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.