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Community Water System · PWS WI2670112

Kewaskum Waterworks

Kewaskum, Wisconsin 53040 - drinking water served from groundwater sources to 4,309 people, tracked in EPA SDWIS and UCMR5.

4,309
People served
137
EPA violations
0
Health-based
2 PFAS
UCMR5 result

The verdict

EPA records 137 drinking-water violations at Kewaskum Waterworks - above the Wisconsin per-system average, and UCMR5 testing detected 2 PFAS compounds.

137
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
4,309
People served by this system
2
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Kewaskum Waterworks

Kewaskum Waterworks is a local-owned community water system that delivers drinking water to 4,309 residents in Kewaskum, Wisconsin (Washington County) through 1,559 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 137 total violations for this system , of which 0 (0%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 135 monitoring and reporting violations are on file. The most recent violation on record dates to 2005.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 5 violations (MR). Under EPA's UCMR5 PFAS monitoring program, 2 PFAS compounds were detected in samples collected from this system, with a maximum reported concentration of 15 ppt (parts per trillion). PFAS are persistent synthetic chemicals linked to health effects at very low exposure levels.

Across Wisconsin, EPA tracks 10,988 public water systems serving 5,131,439 people, with 285,161 cumulative violations and 58,688 health-based violations on record. About 72% of systems in the state carry at least one violation, and state-wide the average per system is 26 violations. Statewide, 78 of 202 UCMR5-tested systems have reported PFAS detections (38.6%).

Kewaskum Waterworks's 137 violations sit above the Wisconsin average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

PFAS Detected

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

Population Served
4,309
Total Violations
137
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
1,559
County
Washington
School/Daycare
No
MCL Violations
0
Monitoring Violations
135
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 5 1993
Endrin MR 4 1993
Toxaphene MR 4 1993
Diquat MR 4 1993
Endothall MR 4 1993
Glyphosate MR 4 1993
Simazine MR 4 1993
Dinoseb MR 4 1993
Aldicarb sulfoxide MR 4 1993
Aldicarb sulfone MR 4 1993
LASSO MR 4 1993
Heptachlor MR 4 1993
Heptachlor epoxide MR 4 1993
2,4-D MR 4 1993
2,4,5-TP MR 4 1993
HEXACHLOROBENZENE MR 4 1993
Pentachlorophenol MR 4 1993
Total Polychlorinated Biphenyls (PCB) MR 4 1993
Chlordane MR 4 1993
BHC-GAMMA MR 4 1993
Methoxychlor MR 4 1993
Dalapon MR 4 1993
OXAMYL MR 4 1993
Picloram MR 4 1993
Carbofuran MR 4 1993
Atrazine MR 4 1993
Hexachlorocyclopentadiene MR 4 1993
Aldicarb MR 4 1993
Consumer Confidence Rule Other 2 2005
1,2,4-Trichlorobenzene MR 1 2001

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 6 of 232 samples detected PFAS.

Contaminant Date Result MRL Status
PFTrDA 8/22/2023 <7.00 ppt 7.00 ppt Not Detected
PFHpS 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
PFTA 8/22/2023 <8.00 ppt 8.00 ppt Not Detected
PFPeA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
NMeFOSAA 8/22/2023 <6.00 ppt 6.00 ppt Not Detected
4:2 FTS 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 8/22/2023 <20.00 ppt 20.00 ppt Not Detected
NEtFOSAA 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFMBA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
ADONA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 8/22/2023 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFPeS 8/22/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 8/22/2023 <4.00 ppt 4.00 ppt Not Detected
9Cl-PF3ONS 8/22/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFUnA 8/22/2023 <2.00 ppt 2.00 ppt Not Detected
PFHxA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
PFDoA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
PFEESA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
PFOA 8/22/2023 15.00 ppt 4.00 ppt Detected
6:2 FTS 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFNA 8/22/2023 <4.00 ppt 4.00 ppt Not Detected
PFHxS 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
PFBS 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFDA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
PFBA 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFTA 8/22/2023 <8.00 ppt 8.00 ppt Not Detected
PFMBA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
ADONA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFMPA 8/22/2023 <4.00 ppt 4.00 ppt Not Detected
PFPeA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
PFEESA 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 8/22/2023 <20.00 ppt 20.00 ppt Not Detected
PFPeS 8/22/2023 <4.00 ppt 4.00 ppt Not Detected
HFPO-DA 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 8/22/2023 <7.00 ppt 7.00 ppt Not Detected
NMeFOSAA 8/22/2023 <6.00 ppt 6.00 ppt Not Detected
PFHpS 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
NEtFOSAA 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFHxS 8/22/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 8/22/2023 <5.00 ppt 5.00 ppt Not Detected
PFBS 8/22/2023 6.60 ppt 3.00 ppt Detected
PFNA 8/22/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 8/22/2023 <4.00 ppt 4.00 ppt Not Detected

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Kewaskum Waterworks.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID WI2670112 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Wisconsin Drinking Water Authority

Wisconsin DNR, Drinking Water and Groundwater is the primacy agency that licenses and inspects Kewaskum Waterworks under EPA-delegated authority.

Open WI regulator portal

Source: Wisconsin DNR, Drinking Water and Groundwater

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2005 Consumer Confidence Rule Other 2 SDWIS / WI2670112 / 7000
2001 1,2,4-Trichlorobenzene MR 1 SDWIS / WI2670112 / 2378
2001 cis-1,2-Dichloroethylene MR 1 SDWIS / WI2670112 / 2380
2001 Xylenes, Total MR 1 SDWIS / WI2670112 / 2955
2001 DICHLOROMETHANE MR 1 SDWIS / WI2670112 / 2964
2001 p-Dichlorobenzene MR 1 SDWIS / WI2670112 / 2969
2001 1,1-Dichloroethylene MR 1 SDWIS / WI2670112 / 2977
2001 trans-1,2-Dichloroethylene MR 1 SDWIS / WI2670112 / 2979
2001 1,1,1-Trichloroethane MR 1 SDWIS / WI2670112 / 2981
2001 1,2-Dichloropropane MR 1 SDWIS / WI2670112 / 2983
2001 Trichloroethylene MR 1 SDWIS / WI2670112 / 2984
2001 1,1,2-Trichloroethane MR 1 SDWIS / WI2670112 / 2985
2001 Tetrachloroethylene MR 1 SDWIS / WI2670112 / 2987
2001 CHLOROBENZENE MR 1 SDWIS / WI2670112 / 2989
2001 Benzene MR 1 SDWIS / WI2670112 / 2990

How Kewaskum Waterworks Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Kewaskum Waterworks Wisconsin avg Federal benchmark
Total violations 137 26 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 0 5.3 Indicates a contaminant exceeded a federal MCL
PFAS detection 2 compounds 38.6% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 4,309 467 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 10,988 regulated public water systems in Wisconsin.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Kewaskum Waterworks water safe to drink? ▼
Kewaskum Waterworks (PWS ID: WI2670112) has 137 recorded violations in the EPA SDWIS database. PFAS contamination has been detected in UCMR5 testing, with 2 PFAS compounds found. This system serves 4,309 people using Groundwater sources.
How many people does Kewaskum Waterworks serve? ▼
Kewaskum Waterworks serves 4,309 people in Kewaskum, Wisconsin. It is a Local-owned system using Groundwater water sources with 1,559 service connections.
What type of violations does Kewaskum Waterworks have? ▼
Kewaskum Waterworks has 137 total violations: 0 health-based violations (MCL exceedances or treatment failures), 135 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Kewaskum Waterworks water? ▼
Yes. UCMR5 testing detected 2 PFAS compounds in Kewaskum Waterworks's water supply: PFOA, PFBS. PFAS are persistent "forever chemicals" that do not break down in the environment.
What water source does Kewaskum Waterworks use? ▼
Kewaskum Waterworks uses Groundwater as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
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.

Read our methodology - how this data is sourced, computed, and verified.

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

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.