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Tap water quality report

Suffolk County Water Authority

EPA monitoring tested this supplier for 31 contaminants and detected 11. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

31
contaminants tested
11
detected
1,100,000
people served
14
health-based violations
New York rankingsLead in New YorkPFAS in New York
Water source
Ground water
Ownership
Local government
Counties served
Suffolk

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.

14
health-based violations
27
violations on file
0
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 2006-09-01 → 2006-09-30
MCL Health-based Resolved 2006-09-01 → 2006-09-30
MCL Health-based Resolved 2006-09-01 → 2006-09-30
MCL Health-based Resolved 2006-09-01 → 2006-09-30
MCL Health-based Resolved 2006-09-01 → 2006-09-30
MCL Health-based Resolved 2002-01-01 → 2002-12-31
MCL Health-based Resolved 2002-01-01 → 2002-12-31

PFAS detected

PFAS are industrial “forever chemicals”. These are the EPA's latest nationwide test results (2023–2025).
ContaminantMaxDetection ratePeriod
Pfpea 0.0394 µg/L 53/480 2025
Pfhxa 0.0435 µg/L 45/480 2025
PFHXS 0.0108 µg/L 19/480 2025
PFOA 0.0065 µg/L 19/480 2025
PFOS 0.0174 µg/L 13/480 2025
Pfba 0.0126 µg/L 9/480 2025
PFBS 0.0052 µg/L 5/480 2025
Pfhpa 0.0096 µg/L 4/480 2025
6:2 Fts 0.0236 µg/L 2/480 2025
PFNA 0.0057 µg/L 2/480 2025

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
Lead
0.0013 mg/L 8.3%
of the EPA limit 0.0150 mg/L
 21/21 LCR 2027
20 contaminants tested, none detected
11Cl-PF3OUdS4:2 Fts8:2 Fts9Cl-PF3ONSAdonaHfpo-DaNetfosaaNfdhaNmefosaaPfdaPfdoaPfeesaPfhpsPfmbaPfmpaPfpesPftaPftrdaPfunaLithium

Utility contact

Contact
SCHNEIDER, THOMAS
Phone
631-563-0258
Email
[email protected]

Frequently asked questions about Suffolk County Water Authority

Is Suffolk County Water Authority tap water safe to drink?

EPA monitoring detected 11 contaminants in Suffolk County Water Authority'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 Suffolk County Water Authority's water?

EPA monitoring detected Pfpea, Pfhxa, Lead, PFHXS, PFOA, and others. The full list with the level and data source for each is above.

How many people does Suffolk County Water Authority serve?

Suffolk County Water Authority reports serving 1,100,000 people in New York, per its EPA record.

Has Suffolk County Water Authority had any water quality violations?

The EPA has 27 violations on file for Suffolk County Water Authority, of which 14 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.