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Tap water quality report

Hyannis Water System, Town of Barnstable

EPA monitoring tested this supplier for 104 contaminants and detected 25. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

104
contaminants tested
25
detected
35,000
people served
9
health-based violations
Massachusetts rankingsLead in MassachusettsPFAS in Massachusetts
Water source
Ground water
Ownership
Local government
Counties served
Barnstable

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.

9
health-based violations
79
violations on file
0
still open
ViolationTypeStatusPeriod
MCL Health-based Resolved 2009-08-01 → 2009-08-31
MCL Health-based Resolved 2009-08-01 → 2009-08-31
MCL Health-based Resolved 2007-11-01 → 2007-11-30
MCL Health-based Resolved 2007-11-01 → 2007-11-30
MCL Health-based Resolved 2007-10-01 → 2007-10-31
MCL Health-based Resolved 2007-10-01 → 2007-10-31
MCL Health-based Archived 2002-12-01 → 2002-12-31
MCL Health-based Archived 2002-12-01 → 2002-12-31
MCL Health-based Resolved 1997-05-01 → 1997-05-31
Other Monitoring Resolved 2017-07-11

PFAS detected

PFAS are industrial “forever chemicals”. These are the EPA's latest nationwide test results (2023–2025).
ContaminantMaxDetection ratePeriod
Pfpea 0.0298 µg/L 4/6 2024
Pfba 0.0168 µg/L 3/6 2024
Pfhxa 0.0065 µg/L 2/6 2024

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 single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Nitrate
5800 µg/L 58%
of the EPA limit 10000 µg/L
 136/142 SYR4 2012–2019
TTHM
23.6 µg/L 30%
of the EPA limit 80 µg/L
 95/103 SYR4 2012–2019
Dibromochloromethane
9.1 µg/L
No EPA limit set
 92/102 SYR4 2013–2019
Bromoform
3.8 µg/L
No EPA limit set
 71/102 SYR4 2013–2019
Bromodichloromethane
8.3 µg/L
No EPA limit set
 70/102 SYR4 2013–2019
Dibromoacetic Acid
3.5 µg/L
No EPA limit set
 61/102 SYR4 2013–2019
Total Haloacetic Acids (HAA5)
10.3 µg/L 17%
of the EPA limit 60 µg/L
 57/98 SYR4 2012–2019
Chloroform
4.5 µg/L
No EPA limit set
 51/102 SYR4 2013–2019
Barium
123 µg/L 6.2%
of the EPA limit 2000 µg/L
 22/23 SYR4 2012–2019
Tetrachloroethylene
2.8 µg/L 56%
of the EPA limit 5 µg/L
 21/150 SYR4 2012–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 18/18 LCR 2025
Dichloroacetic Acid
2.2 µg/L
No EPA limit set
 15/102 SYR4 2013–2019
Arsenic
4 µg/L 40%
of the EPA limit 10 µg/L
 10/23 SYR4 2012–2019
Trichloroacetic Acid
2.1 µg/L
No EPA limit set
 9/102 SYR4 2013–2019
Copper
604 µg/L 46%
of the EPA limit 1300 µg/L
 8/33 SYR4 2014–2019
Selenium
4 µg/L 8%
of the EPA limit 50 µg/L
 6/23 SYR4 2012–2019
Cadmium
0.2100 µg/L 4.2%
of the EPA limit 5 µg/L
 4/23 SYR4 2012–2019
Monochloroacetic Acid
4.3 µg/L
No EPA limit set
 4/102 SYR4 2013–2019
Fluoride
80 µg/L 2%
of the EPA limit 4000 µg/L
 3/30 SYR4 2012–2019
Monobromoacetic Acid
3.9 µg/L
No EPA limit set
 1/102 SYR4 2013–2019
Trichloroethylene
0.6500 µg/L 13%
of the EPA limit 5 µg/L
 1/78 SYR4 2012–2019
cis-1,2-Dichloroethylene
2 µg/L 2.9%
of the EPA limit 70 µg/L
 1/78 SYR4 2012–2019
79 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, TotalAsbestosAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCyanideCarbofuranCarbon TetrachlorideChlordaneChromiumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebEthylene DibromideEndrinEthylbenzeneGlyphosateHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorNetfosaaNfdhaNmefosaaNitriteOxamylPFBSPfdaPfdoaPfeesaPfhpaPfhpsPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpesPftaPftrdaPfunaPentachlorophenolPicloramSimazineStyreneThallium, TotalTolueneToxapheneVinyl ChlorideXylenes, TotalLithiumO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
HENRICUS C KEIJSER
Phone
5087750063
Email
HANS.KEIJSER@TOWN.BARNSTABLE.MA.US

Frequently asked questions about Hyannis Water System, Town of Barnstable

Is Hyannis Water System, Town of Barnstable tap water safe to drink?

EPA monitoring detected 25 contaminants in Hyannis Water System, Town of Barnstable'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 Hyannis Water System, Town of Barnstable's water?

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

How many people does Hyannis Water System, Town of Barnstable serve?

Hyannis Water System, Town of Barnstable reports serving 35,000 people in Massachusetts, per its EPA record.

Has Hyannis Water System, Town of Barnstable had any water quality violations?

The EPA has 79 violations on file for Hyannis Water System, Town of Barnstable, of which 9 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.