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Community Water System · PWS NY5110526

Suffolk County Water Authority

Operator location Hauppauge, New York - 33% of 42 violations are health-based (upper-third health share (> 23%)); groundwater source; 1,100,000 served per SDWIS.

1,100,000
People served (this PWS)
42
EPA violations (this PWS)
14
Health-based (this PWS)
10 PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

Suffolk County Water Authority standing, mid SDWIS violation third

33% of 42 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 33% is upper-third health share (> 23%). UCMR5: upper-third PFAS panel (> 4 compounds). Population rank #23 of 29,740 among systems serving 500+.

The verdict

Suffolk County Water Authority lands in the middle third by violation volume (42), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is large (1,100,000; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 33% - most of this ledger is MCL or treatment-technique exceedance. UCMR5 detected 10 PFAS compounds (upper-third PFAS panel (> 4 compounds)).

#23 of 29,740
Population · /systems
#2 of 1,204
Population · NY
42
Total EPA violations on record
33%
Health-based (MCL / treatment failure)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

PFAS Detected

10 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.

System Details

System Type
Community
Owner Type
Local
Connections
336,418
County
Suffolk
School/Daycare
No
MCL Violations
14
Monitoring Violations
13
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Nitrate MCL 6 2002
Coliform (TCR) MCL 5 2006
Revised Total Coliform Rule MON 4 2018
Radium-228 MR 3 2008
Asbestos MCL 3 2020
Endrin MR 1 1985
2,4-D MR 1 1985
Toxaphene MR 1 1985
Methoxychlor MR 1 1985
BHC-GAMMA MR 1 1985
2,4,5-TP MR 1 1985

Violation Count vs. the National Corpus

Suffolk County Water Authority has 42 recorded EPA violations, 52% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 48% carry more. 33% of this system's own violations are health-based (14 of 42), and it ranks #23 of 29,740 by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

42 Around the middle fewer violations than 48% of 29,740 water systems

the national water-system corpus, bucketed by value

Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source EPA SDWIS · 2026-05-15

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 171 of 13936 samples detected PFAS.

Contaminant Date Result MRL Status
PFUnA 9/9/2024 <2.00 ppt 2.00 ppt Not Detected
PFDoA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
NEtFOSAA 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 9/9/2024 <7.00 ppt 7.00 ppt Not Detected
PFTA 9/9/2024 <8.00 ppt 8.00 ppt Not Detected
PFHpS 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeS 9/9/2024 <4.00 ppt 4.00 ppt Not Detected
NFDHA 9/9/2024 <20.00 ppt 20.00 ppt Not Detected
PFEESA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFMBA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFMPA 9/9/2024 <4.00 ppt 4.00 ppt Not Detected
9Cl-PF3ONS 9/9/2024 <2.00 ppt 2.00 ppt Not Detected
NMeFOSAA 9/9/2024 <6.00 ppt 6.00 ppt Not Detected
6:2 FTS 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
PFPeA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFDA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFOA 9/9/2024 <4.00 ppt 4.00 ppt Not Detected
PFOS 9/9/2024 <4.00 ppt 4.00 ppt Not Detected
PFNA 9/9/2024 <4.00 ppt 4.00 ppt Not Detected
PFHxS 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFBS 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFBA 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
ADONA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
11Cl-PF3OUdS 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
PFHxA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
NFDHA 9/9/2024 <20.00 ppt 20.00 ppt Not Detected
6:2 FTS 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
PFMPA 9/9/2024 <4.00 ppt 4.00 ppt Not Detected
PFPeA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFBA 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
PFEESA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpS 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeS 9/9/2024 <4.00 ppt 4.00 ppt Not Detected
PFTA 9/9/2024 <8.00 ppt 8.00 ppt Not Detected
NEtFOSAA 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 9/9/2024 <6.00 ppt 6.00 ppt Not Detected
PFMBA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxS 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFTrDA 9/9/2024 <7.00 ppt 7.00 ppt Not Detected
HFPO-DA 9/9/2024 <5.00 ppt 5.00 ppt Not Detected
PFBS 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/9/2024 <3.00 ppt 3.00 ppt Not Detected
PFNA 9/9/2024 <4.00 ppt 4.00 ppt Not Detected
PFOS 9/9/2024 <4.00 ppt 4.00 ppt Not Detected

Health-based violations on Suffolk County Water Authority

14 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for NY5110526.

Sources: EPA SDWIS · New York State Department of Health, Public Water Systems

Nationwide peers

42 violations · 1,100,000 served: nearest cross-state SDWIS matches.

What to do with Suffolk County Water Authority

Use this system's EPA-reported record as a starting filter, not a final verdict.

  • See how every tracked system in New York compares on the same EPA violation measures. New York systems
  • Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
  • Find and compare another public water system by name or PWSID. Search systems

EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater