CheckPFAS

PORTSMOUTH WATER WORKS

High Risk
PWSID: NH1951010 New Hampshire Surface Water

2 PFAS compound(s) exceed EPA Maximum Contaminant Levels

This utility has until 2029 to install treatment under the EPA's April 2024 PFAS rule. In the meantime, a point-of-use filter certified NSF/ANSI 58 for PFOA/PFOS provides reliable interim protection.

9
PFAS Detected
2
Above EPA Limits
5
ZIPs Served
Surface
Water Source

PFAS Test Results

CompoundDetectedvs. EPA LimitEPA LimitStatus
PFOA
Perfluorooctanoic acid
7.00ppt
175% of limit
4 ppt⚠ Exceeds MCL
PFOS
Perfluorooctane sulfonic acid
5.00ppt
125% of limit
4 ppt⚠ Exceeds MCL
PFHxS
Perfluorohexane sulfonic acid
5.00ppt
50% of limit
10 pptBelow limit
lithium
10000.00pptNo federal limitUnregulated
PFBS
Perfluorobutane sulfonic acid
9.00pptNo federal limitUnregulated
PFPeA
Perfluoropentanoic acid
7.00pptNo federal limitUnregulated
PFHxA
Perfluorohexanoic acid
6.00pptNo federal limitUnregulated
PFBA
Perfluorobutanoic acid
5.00pptNo federal limitUnregulated
Show 1 more compound detected at low levels
PFHpAPerfluoroheptanoic acid3.00 pptNo federal limit

ZIP Codes Served by This Utility

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About this data
Source
EPA UCMR 5 — January 2026 release
Sampling period
January 2023 – December 2025
Water system ID (PWSID)
NH1951010
Detection threshold (MRL)
~1.5–2 ppt — "Not detected" means below this floor