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Community Water System · PWS WI1250076

Cobb Waterworks

Cobb, Wisconsin 53526 - drinking water served from groundwater sources to 458 people, tracked in EPA SDWIS and UCMR5.

458
People served
137
EPA violations
1
Health-based
Untested
UCMR5 result

The verdict

EPA records 137 drinking-water violations at Cobb Waterworks, 1% of them health-based - above the Wisconsin per-system average.

137
Total EPA violations on record
1%
Health-based (MCL / treatment failure)
458
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Cobb Waterworks

Cobb Waterworks is a local-owned community water system that delivers drinking water to 458 residents in Cobb, Wisconsin (Iowa County) through 169 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 1 (1%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 128 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 10 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

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%).

Cobb 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.

Population Served
458
Total Violations
137
Health-Based Violations
1
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
169
County
Iowa
School/Daycare
No
MCL Violations
0
Monitoring Violations
128
Treatment Tech Violations
1

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 10 2016
Radium-228 MR 8 2020
1,1,1-Trichloroethane MR 4 2020
DICHLOROMETHANE MR 4 2020
Carbon tetrachloride MR 4 2020
Trichloroethylene MR 4 2020
CHLOROBENZENE MR 4 2020
Ethylbenzene MR 4 2020
cis-1,2-Dichloroethylene MR 4 2020
Radium-226 MR 4 2020
Gross Alpha, Excl. Radon and U MR 4 2020
Revised Total Coliform Rule MON 4 2021
1,1,2-Trichloroethane MR 4 2020
Styrene MR 4 2020
Xylenes, Total MR 4 2020
1,2-Dichloropropane MR 4 2020
Benzene MR 4 2020
trans-1,2-Dichloroethylene MR 4 2020
Tetrachloroethylene MR 4 2020
Vinyl chloride MR 4 2020
1,2-Dichloroethane MR 4 2020
1,2,4-Trichlorobenzene MR 4 2020
p-Dichlorobenzene MR 4 2020
1,1-Dichloroethylene MR 4 2020
Combined Uranium MR 4 2020
o-Dichlorobenzene MR 4 2020
Toluene MR 4 2020
Chlorine MR 4 2016
Combined Radium (-226 and -228) MR 4 2020
Lead and Copper Rule MR 2 2012

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 Cobb 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 WI1250076 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 Cobb 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
2025 LEAD AND COPPER RULE REVISIONS RPT 1 SDWIS / WI1250076 / 5200
2024 LEAD AND COPPER RULE REVISIONS TT 1 SDWIS / WI1250076 / 5200
2024 Public Notice Other 1 SDWIS / WI1250076 / 7500
2021 Revised Total Coliform Rule MON 4 SDWIS / WI1250076 / 8000
2020 Radium-228 MR 8 SDWIS / WI1250076 / 4030
2020 1,1,1-Trichloroethane MR 4 SDWIS / WI1250076 / 2981
2020 DICHLOROMETHANE MR 4 SDWIS / WI1250076 / 2964
2020 Carbon tetrachloride MR 4 SDWIS / WI1250076 / 2982
2020 Trichloroethylene MR 4 SDWIS / WI1250076 / 2984
2020 CHLOROBENZENE MR 4 SDWIS / WI1250076 / 2989
2020 Ethylbenzene MR 4 SDWIS / WI1250076 / 2992
2020 cis-1,2-Dichloroethylene MR 4 SDWIS / WI1250076 / 2380
2020 Radium-226 MR 4 SDWIS / WI1250076 / 4020
2020 Gross Alpha, Excl. Radon and U MR 4 SDWIS / WI1250076 / 4000
2020 1,1,2-Trichloroethane MR 4 SDWIS / WI1250076 / 2985

How Cobb Waterworks Compares

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

Metric Cobb Waterworks Wisconsin avg Federal benchmark
Total violations 137 26 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 1 5.3 Indicates a contaminant exceeded a federal MCL
PFAS detection None 38.6% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 458 467 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 Cobb Waterworks water safe to drink? ▼
Cobb Waterworks (PWS ID: WI1250076) has 137 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 458 people using Groundwater sources.
How many people does Cobb Waterworks serve? ▼
Cobb Waterworks serves 458 people in Cobb, Wisconsin. It is a Local-owned system using Groundwater water sources with 169 service connections.
What type of violations does Cobb Waterworks have? ▼
Cobb Waterworks has 137 total violations: 1 health-based violations (MCL exceedances or treatment failures), 128 monitoring/reporting violations, and 1 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Cobb Waterworks water? ▼
No PFAS testing data is available for Cobb Waterworks under the EPA's UCMR5 monitoring program.
What water source does Cobb Waterworks use? ▼
Cobb 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. 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.