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Community Water System · PWS WI2680761

St Johns Northwestern Academies

Delafield, Wisconsin 53018 - drinking water served from groundwater sources to 340 people, tracked in EPA SDWIS and UCMR5.

340
People served
222
EPA violations
12
Health-based
Untested
UCMR5 result

The verdict

EPA records 222 drinking-water violations at St Johns Northwestern Academies, 5% of them health-based - above the Wisconsin per-system average.

222
Total EPA violations on record
5%
Health-based (MCL / treatment failure)
340
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: St Johns Northwestern Academies

St Johns Northwestern Academies is a private-owned community water system that delivers drinking water to 340 residents in Delafield, Wisconsin (Waukesha County) through 12 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 222 total violations for this system , of which 12 (5%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 192 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 15 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, 51 of 202 UCMR5-tested systems have reported PFAS detections (25.2%).

St Johns Northwestern Academies's 222 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
340
Total Violations
222
Health-Based Violations
12
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
12
County
Waukesha
School/Daycare
Yes
MCL Violations
9
Monitoring Violations
192
Treatment Tech Violations
3

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 15 2009
Consumer Confidence Rule Other 14 2015
Revised Total Coliform Rule MON 13 2022
Coliform (TCR) MCL 9 2001
Chlorine MR 8 2022
Nitrate MR 6 2002
1,2,4-Trichlorobenzene MR 6 2010
cis-1,2-Dichloroethylene MR 6 2010
Xylenes, Total MR 6 2010
o-Dichlorobenzene MR 6 2010
Vinyl chloride MR 6 2010
1,1-Dichloroethylene MR 6 2010
trans-1,2-Dichloroethylene MR 6 2010
Trichloroethylene MR 6 2010
CHLOROBENZENE MR 6 2010
Ethylbenzene MR 6 2010
Gross Alpha, Excl. Radon and U MR 6 2010
Radium-228 MR 6 2010
Lead and Copper Rule MR 6 2022
Styrene MR 6 2010
Tetrachloroethylene MR 6 2010
Benzene MR 6 2010
Toluene MR 6 2010
1,1,1-Trichloroethane MR 6 2010
Carbon tetrachloride MR 6 2010
Combined Radium (-226 and -228) MR 6 2010
p-Dichlorobenzene MR 6 2010
1,2-Dichloropropane MR 6 2010
DICHLOROMETHANE MR 6 2010
1,1,2-Trichloroethane MR 6 2010

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 St Johns Northwestern Academies.

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 WI2680761 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 St Johns Northwestern Academies 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
2024 Public Notice Other 3 SDWIS / WI2680761 / 7500
2024 LEAD AND COPPER RULE REVISIONS TT 1 SDWIS / WI2680761 / 5200
2024 LEAD AND COPPER RULE REVISIONS RPT 1 SDWIS / WI2680761 / 5200
2022 Revised Total Coliform Rule MON 13 SDWIS / WI2680761 / 8000
2022 Chlorine MR 8 SDWIS / WI2680761 / 0999
2022 Lead and Copper Rule MR 6 SDWIS / WI2680761 / 5000
2021 Stage 1 Disinfectants and Disinfection Byproducts Rule TT 2 SDWIS / WI2680761 / 0400
2015 Consumer Confidence Rule Other 14 SDWIS / WI2680761 / 7000
2010 1,2,4-Trichlorobenzene MR 6 SDWIS / WI2680761 / 2378
2010 cis-1,2-Dichloroethylene MR 6 SDWIS / WI2680761 / 2380
2010 Xylenes, Total MR 6 SDWIS / WI2680761 / 2955
2010 o-Dichlorobenzene MR 6 SDWIS / WI2680761 / 2968
2010 Vinyl chloride MR 6 SDWIS / WI2680761 / 2976
2010 1,1-Dichloroethylene MR 6 SDWIS / WI2680761 / 2977
2010 trans-1,2-Dichloroethylene MR 6 SDWIS / WI2680761 / 2979

How St Johns Northwestern Academies Compares

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

Metric St Johns Northwestern Academies Wisconsin avg Federal benchmark
Total violations 222 26 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 12 5.3 Indicates a contaminant exceeded a federal MCL
PFAS detection None 25.2% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 340 467 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 St Johns Northwestern Academies water safe to drink? ▼
St Johns Northwestern Academies (PWS ID: WI2680761) has 222 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 340 people using Groundwater sources.
How many people does St Johns Northwestern Academies serve? ▼
St Johns Northwestern Academies serves 340 people in Delafield, Wisconsin. It is a Private-owned system using Groundwater water sources with 12 service connections.
What type of violations does St Johns Northwestern Academies have? ▼
St Johns Northwestern Academies has 222 total violations: 12 health-based violations (MCL exceedances or treatment failures), 192 monitoring/reporting violations, and 3 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in St Johns Northwestern Academies water? ▼
No PFAS testing data is available for St Johns Northwestern Academies under the EPA's UCMR5 monitoring program.
What water source does St Johns Northwestern Academies use? ▼
St Johns Northwestern Academies 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.