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Community Water System · PWS WI1250087

Ridgeway Waterworks

Ridgeway, Wisconsin 53582 - drinking water served from groundwater sources to 690 people, tracked in EPA SDWIS and UCMR5.

690
People served
245
EPA violations
26
Health-based
Untested
UCMR5 result

The verdict

EPA records 245 drinking-water violations at Ridgeway Waterworks, 11% of them health-based - above the Wisconsin per-system average.

245
Total EPA violations on record
11%
Health-based (MCL / treatment failure)
690
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Ridgeway Waterworks

Ridgeway Waterworks is a local-owned community water system that delivers drinking water to 690 residents in Ridgeway, Wisconsin (Iowa County) through 255 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 245 total violations for this system , of which 26 (11%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 209 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 22 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%).

Ridgeway Waterworks's 245 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
690
Total Violations
245
Health-Based Violations
26
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
255
County
Iowa
School/Daycare
No
MCL Violations
26
Monitoring Violations
209
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 22 2003
Coliform (TCR) MCL 18 2005
1,2,4-Trichlorobenzene MR 8 2003
DICHLOROMETHANE MR 8 2003
p-Dichlorobenzene MR 8 2003
trans-1,2-Dichloroethylene MR 8 2003
1,2-Dichloroethane MR 8 2003
Carbon tetrachloride MR 8 2003
1,2-Dichloropropane MR 8 2003
Trichloroethylene MR 8 2003
1,1,2-Trichloroethane MR 8 2003
Tetrachloroethylene MR 8 2003
CHLOROBENZENE MR 8 2003
Benzene MR 8 2003
Toluene MR 8 2003
cis-1,2-Dichloroethylene MR 8 2003
Vinyl chloride MR 8 2003
1,1-Dichloroethylene MR 8 2003
1,1,1-Trichloroethane MR 8 2003
Styrene MR 8 2003
Radium-228 MR 8 2009
o-Dichlorobenzene MR 8 2003
Combined Radium (-226 and -228) MCL 8 2024
Ethylbenzene MR 8 2003
Xylenes, Total MR 8 2003
TTHM MR 4 2015
Total Haloacetic Acids (HAA5) MR 4 2015
Revised Total Coliform Rule MON 3 2025

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 Ridgeway 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 WI1250087 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 Ridgeway 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 Revised Total Coliform Rule MON 3 SDWIS / WI1250087 / 8000
2024 Combined Radium (-226 and -228) MCL 8 SDWIS / WI1250087 / 4010
2015 TTHM MR 4 SDWIS / WI1250087 / 2950
2015 Total Haloacetic Acids (HAA5) MR 4 SDWIS / WI1250087 / 2456
2009 Radium-228 MR 8 SDWIS / WI1250087 / 4030
2005 Coliform (TCR) MCL 18 SDWIS / WI1250087 / 3100
2003 Coliform (TCR) MR 22 SDWIS / WI1250087 / 3100
2003 1,2,4-Trichlorobenzene MR 8 SDWIS / WI1250087 / 2378
2003 DICHLOROMETHANE MR 8 SDWIS / WI1250087 / 2964
2003 p-Dichlorobenzene MR 8 SDWIS / WI1250087 / 2969
2003 trans-1,2-Dichloroethylene MR 8 SDWIS / WI1250087 / 2979
2003 1,2-Dichloroethane MR 8 SDWIS / WI1250087 / 2980
2003 Carbon tetrachloride MR 8 SDWIS / WI1250087 / 2982
2003 1,2-Dichloropropane MR 8 SDWIS / WI1250087 / 2983
2003 Trichloroethylene MR 8 SDWIS / WI1250087 / 2984

How Ridgeway Waterworks Compares

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

Metric Ridgeway Waterworks Wisconsin avg Federal benchmark
Total violations 245 26 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 26 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 690 467 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 Ridgeway Waterworks water safe to drink? ▼
Ridgeway Waterworks (PWS ID: WI1250087) has 245 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 690 people using Groundwater sources.
How many people does Ridgeway Waterworks serve? ▼
Ridgeway Waterworks serves 690 people in Ridgeway, Wisconsin. It is a Local-owned system using Groundwater water sources with 255 service connections.
What type of violations does Ridgeway Waterworks have? ▼
Ridgeway Waterworks has 245 total violations: 26 health-based violations (MCL exceedances or treatment failures), 209 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Ridgeway Waterworks water? ▼
No PFAS testing data is available for Ridgeway Waterworks under the EPA's UCMR5 monitoring program.
What water source does Ridgeway Waterworks use? ▼
Ridgeway 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.