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Tap water quality report

Alton Water Works

EPA monitoring tested this supplier for 75 contaminants and detected 17. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

75
contaminants tested
17
detected
1,800
people served
66
health-based violations
New Hampshire rankingsLead in New HampshirePFAS in New Hampshire
Water source
Ground water
Ownership
Local government
Counties served
Belknap

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.

66
health-based violations
413
violations on file
1
still open
ViolationTypeStatusPeriod
MCL Health-based Resolved 2020-07-01 → 2020-09-30
MCL Health-based Resolved 2020-07-01 → 2020-09-30
MCL Health-based Resolved 2020-07-01 → 2020-09-30
MCL Health-based Resolved 2020-07-01 → 2020-09-30
MCL Health-based Resolved 2020-04-01 → 2020-06-30
MCL Health-based Resolved 2020-04-01 → 2020-06-30
MCL Health-based Resolved 2020-04-01 → 2020-06-30
MCL Health-based Resolved 2020-04-01 → 2020-06-30
MCL Health-based Resolved 2011-09-01 → 2011-09-30
MCL Health-based Resolved 2011-09-01 → 2011-09-30

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.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Nitrate
1000 µg/L 10%
of the EPA limit 10000 µg/L
 20/24 SYR4 2014–2019
Copper
892 µg/L 69%
of the EPA limit 1300 µg/L
worst single sample: 1300 µg/L
17/17 SYR4 2014–2018
Lead
14.1 µg/L 94%
of the EPA limit 15 µg/L
worst single sample: 18 µg/L
14/14 SYR4 2015–2018
TTHM
3.185 µg/L 4%
of the EPA limit 80 µg/L
worst single sample: 3.5 µg/L
8/8 SYR4 2014–2017
Bromoform
2.39 µg/L
No EPA limit set
worst single sample: 2.6 µg/L
7/18 SYR4 2014–2019
Dibromochloromethane
0.9700 µg/L
No EPA limit set
worst single sample: 1 µg/L
7/18 SYR4 2014–2019
Lead
0.2100 mg/L 1400%
above the EPA limit of 0.0150 mg/L
 5/5 LCR 2024
Barium
15.9 µg/L 0.8%
of the EPA limit 2000 µg/L
worst single sample: 16 µg/L
3/3 SYR4 2014–2017
Bromodichloromethane
0.7950 µg/L
No EPA limit set
worst single sample: 0.8000 µg/L
2/18 SYR4 2014–2019
Combined Radium (-226 And -228)
0.8950 pCi/L 18%
of the EPA limit 5 pCi/L
worst single sample: 0.9000 pCi/L
2/2 SYR4 2015–2016
Combined Uranium
0.3000 µg/L 1%
of the EPA limit 30 µg/L
 2/3 SYR4 2015–2016
Dichloroacetic Acid
13.455 µg/L
No EPA limit set
worst single sample: 14 µg/L
2/8 SYR4 2014–2017
Total Haloacetic Acids (HAA5)
14.93 µg/L 25%
of the EPA limit 60 µg/L
worst single sample: 15.3 µg/L
2/8 SYR4 2014–2017
Antimony, Total
1 µg/L 17%
of the EPA limit 6 µg/L
 1/3 SYR4 2014–2017
Dibromoacetic Acid
1.3 µg/L
No EPA limit set
 1/8 SYR4 2014–2017
Gross Alpha, Excl. Radon And U
1.6 pCi/L 11%
of the EPA limit 15 pCi/L
 1/2 SYR4 2015–2016
Trichloroacetic Acid
4.8 µg/L
No EPA limit set
 1/8 SYR4 2014–2017
58 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane2,4,5-TP2,4-DArsenicAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCadmiumCarbofuranCarbon TetrachlorideChlordaneChloroformChromiumDichloromethaneDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebEthylene DibromideEndrinEthylbenzeneFluorideGlyphosateHexachlorobenzeneHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonobromoacetic AcidMonochloroacetic AcidNitriteOxamylPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
COURTNEY MITCHELL

Frequently asked questions about Alton Water Works

Is Alton Water Works tap water safe to drink?

EPA monitoring detected 17 contaminants in Alton 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 Alton Water Works's water?

EPA monitoring detected Nitrate, Copper, Lead, TTHM, Bromoform, and others. The full list with the level and data source for each is above.

How many people does Alton Water Works serve?

Alton Water Works reports serving 1,800 people in New Hampshire, per its EPA record.

Has Alton Water Works had any water quality violations?

The EPA has 413 violations on file for Alton Water Works, of which 66 are health-based (a contaminant limit or required treatment was breached) and 1 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.