PlainWater
States → Wisconsin

OCONTO WATERWORKS

PWS ID: WI4430495 · OCONTO, Wisconsin 54153-1542

PFAS Detected

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

Population Served
4,610
Total Violations
33
Health-Based Violations
15
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
1,707
County
Oconto
School/Daycare
No
MCL Violations
13
Monitoring Violations
9
Treatment Tech Violations
2

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Combined Radium (-226 and -228) MCL 13 2019
Coliform (TCR) MR 7 1999
Lead and Copper Rule MR 2 1992
LEAD AND COPPER RULE REVISIONS TT 2 2024
Public Notice Other 1 2024

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 3 of 90 samples detected PFAS.

Contaminant Date Result MRL Status
PFPeS 5/21/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFUnA 5/21/2025 <0.002 µg/L 0.002 µg/L Not Detected
PFNA 5/21/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFHxS 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFOS 5/21/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFHpS 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
4:2 FTS 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
lithium 5/21/2025 16.0000 µg/L 9 µg/L Detected
PFTA 5/21/2025 <0.008 µg/L 0.008 µg/L Not Detected
PFTrDA 5/21/2025 <0.007 µg/L 0.007 µg/L Not Detected
NEtFOSAA 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
NMeFOSAA 5/21/2025 <0.006 µg/L 0.006 µg/L Not Detected
PFBS 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFHpA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
9Cl-PF3ONS 5/21/2025 <0.002 µg/L 0.002 µg/L Not Detected
ADONA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
HFPO-DA 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
PFBA 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
8:2 FTS 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
PFEESA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFMBA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
NFDHA 5/21/2025 <0.02 µg/L 0.02 µg/L Not Detected
PFMPA 5/21/2025 <0.004 µg/L 0.004 µg/L Not Detected
6:2 FTS 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
11Cl-PF3OUdS 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
PFHxA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFDoA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFDA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFOA 5/21/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFPeA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFBA 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
HFPO-DA 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
lithium 5/21/2025 14.0000 µg/L 9 µg/L Detected
PFMPA 5/21/2025 <0.004 µg/L 0.004 µg/L Not Detected
8:2 FTS 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
4:2 FTS 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFDA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFTA 5/21/2025 <0.008 µg/L 0.008 µg/L Not Detected
PFTrDA 5/21/2025 <0.007 µg/L 0.007 µg/L Not Detected
NEtFOSAA 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
NMeFOSAA 5/21/2025 <0.006 µg/L 0.006 µg/L Not Detected
PFBS 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFHpA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFHxS 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFNA 5/21/2025 <0.004 µg/L 0.004 µg/L Not Detected
6:2 FTS 5/21/2025 <0.005 µg/L 0.005 µg/L Not Detected
PFOA 5/21/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFDoA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFHpS 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFEESA 5/21/2025 <0.003 µg/L 0.003 µg/L Not Detected
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. PFAS data from EPA UCMR5 monitoring program (2023-2025). This data is provided for informational purposes only.