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Non-Transient Non-Community Water System · PWS WI2680511

St Marys School & St Marys Parish

Elm Grove, Wisconsin 53122 - drinking water served from groundwater sources to 606 people, tracked in EPA SDWIS and UCMR5.

606
People served
95
EPA violations
0
Health-based
Untested
UCMR5 result

The verdict

EPA records 95 drinking-water violations at St Marys School & St Marys Parish - above the Wisconsin per-system average.

95
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
606
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: St Marys School & St Marys Parish

St Marys School & St Marys Parish is a private-owned non-transient non-community water system that delivers drinking water to 606 residents in Elm Grove, Wisconsin (Waukesha County) through 1 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 95 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 88 monitoring and reporting violations are on file. The most recent violation on record dates to 2014.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 7 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%).

St Marys School & St Marys Parish's 95 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
606
Total Violations
95
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Non-Transient Non-Community
Owner Type
Private
Connections
1
County
Waukesha
School/Daycare
Yes
MCL Violations
0
Monitoring Violations
88
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 7 1995
Mercury MR 6 2001
Fluoride MR 3 1999
Nitrite MR 3 1999
Selenium MR 3 1999
Arsenic MR 3 1999
Nitrate MR 3 1999
Nitrate-Nitrite MR 3 1999
Chromium MR 3 1999
Cadmium MR 3 1999
Barium MR 3 1999
Lead and Copper Rule MR 2 2014
1,1,2-Trichloroethane MR 2 1995
CHLOROBENZENE MR 2 1995
o-Dichlorobenzene MR 2 1995
Vinyl chloride MR 2 1995
trans-1,2-Dichloroethylene MR 2 1995
1,2-Dichloroethane MR 2 1995
1,1,1-Trichloroethane MR 2 1995
Carbon tetrachloride MR 2 1995
Benzene MR 2 1995
Toluene MR 2 1995
Styrene MR 2 1995
1,2,4-Trichlorobenzene MR 2 1995
DICHLOROMETHANE MR 2 1995
cis-1,2-Dichloroethylene MR 2 1995
Trichloroethylene MR 2 1995
Ethylbenzene MR 2 1995
Xylenes, Total MR 2 1995
1,1-Dichloroethylene MR 2 1995

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 Marys School & St Marys Parish.

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 WI2680511 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 Marys School & St Marys Parish 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
2014 Lead and Copper Rule MR 2 SDWIS / WI2680511 / 5000
2001 Mercury MR 6 SDWIS / WI2680511 / 1035
1999 Fluoride MR 3 SDWIS / WI2680511 / 1025
1999 Nitrite MR 3 SDWIS / WI2680511 / 1041
1999 Selenium MR 3 SDWIS / WI2680511 / 1045
1999 Arsenic MR 3 SDWIS / WI2680511 / 1005
1999 Nitrate MR 3 SDWIS / WI2680511 / 1040
1999 Nitrate-Nitrite MR 3 SDWIS / WI2680511 / 1038
1999 Chromium MR 3 SDWIS / WI2680511 / 1020
1999 Cadmium MR 3 SDWIS / WI2680511 / 1015
1999 Barium MR 3 SDWIS / WI2680511 / 1010
1999 Antimony, Total MR 1 SDWIS / WI2680511 / 1074
1999 Beryllium, Total MR 1 SDWIS / WI2680511 / 1075
1999 Thallium, Total MR 1 SDWIS / WI2680511 / 1085
1999 Nickel MR 1 SDWIS / WI2680511 / 1036

How St Marys School & St Marys Parish Compares

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

Metric St Marys School & St Marys Parish Wisconsin avg Federal benchmark
Total violations 95 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 None 38.6% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 606 467 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 Marys School & St Marys Parish water safe to drink? ▼
St Marys School & St Marys Parish (PWS ID: WI2680511) has 95 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 606 people using Groundwater sources.
How many people does St Marys School & St Marys Parish serve? ▼
St Marys School & St Marys Parish serves 606 people in Elm Grove, Wisconsin. It is a Private-owned system using Groundwater water sources with 1 service connections.
What type of violations does St Marys School & St Marys Parish have? ▼
St Marys School & St Marys Parish has 95 total violations: 0 health-based violations (MCL exceedances or treatment failures), 88 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in St Marys School & St Marys Parish water? ▼
No PFAS testing data is available for St Marys School & St Marys Parish under the EPA's UCMR5 monitoring program.
What water source does St Marys School & St Marys Parish use? ▼
St Marys School & St Marys Parish uses Groundwater as its primary water source. It is classified as a Non-Transient Non-Community Water System, serving the same people for at least 6 months per year.
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.