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Community Water System · PWS WI7010114

Preston Pines

Oconomowoc, Wisconsin 53066 - drinking water served from groundwater sources to 38 people, tracked in EPA SDWIS and UCMR5.

38
People served
77
EPA violations
0
Health-based
Untested
UCMR5 result

The verdict

EPA records 77 drinking-water violations at Preston Pines - above the Wisconsin per-system average.

77
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
38
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Preston Pines

Preston Pines is a private-owned community water system that delivers drinking water to 38 residents in Oconomowoc, Wisconsin (Adams County) through 24 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 77 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 64 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 14 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%).

Preston Pines's 77 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
38
Total Violations
77
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
24
County
Adams
School/Daycare
No
MCL Violations
0
Monitoring Violations
64
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 14 2010
Consumer Confidence Rule Other 13 2018
Lead and Copper Rule MR 4 2019
Revised Total Coliform Rule MON 4 2024
1,2-Dichloroethane MR 2 1996
Vinyl chloride MR 2 1996
Toluene MR 2 1996
DICHLOROMETHANE MR 2 1996
1,1,2-Trichloroethane MR 2 1996
1,2-Dichloropropane MR 2 1996
trans-1,2-Dichloroethylene MR 2 1996
1,1-Dichloroethylene MR 2 1996
p-Dichlorobenzene MR 2 1996
CHLOROBENZENE MR 2 1996
Tetrachloroethylene MR 2 1996
1,2,4-Trichlorobenzene MR 2 1996
cis-1,2-Dichloroethylene MR 2 1996
o-Dichlorobenzene MR 2 1996
Styrene MR 2 1996
Benzene MR 2 1996
Trichloroethylene MR 2 1996
1,1,1-Trichloroethane MR 2 1996
Ethylbenzene MR 2 1996
Xylenes, Total MR 2 1996
Carbon tetrachloride MR 2 1996

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 Preston Pines.

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 WI7010114 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 Preston Pines 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 Revised Total Coliform Rule MON 4 SDWIS / WI7010114 / 8000
2019 Lead and Copper Rule MR 4 SDWIS / WI7010114 / 5000
2018 Consumer Confidence Rule Other 13 SDWIS / WI7010114 / 7000
2010 Coliform (TCR) MR 14 SDWIS / WI7010114 / 3100
1996 1,2-Dichloroethane MR 2 SDWIS / WI7010114 / 2980
1996 Vinyl chloride MR 2 SDWIS / WI7010114 / 2976
1996 Toluene MR 2 SDWIS / WI7010114 / 2991
1996 DICHLOROMETHANE MR 2 SDWIS / WI7010114 / 2964
1996 1,1,2-Trichloroethane MR 2 SDWIS / WI7010114 / 2985
1996 1,2-Dichloropropane MR 2 SDWIS / WI7010114 / 2983
1996 trans-1,2-Dichloroethylene MR 2 SDWIS / WI7010114 / 2979
1996 1,1-Dichloroethylene MR 2 SDWIS / WI7010114 / 2977
1996 p-Dichlorobenzene MR 2 SDWIS / WI7010114 / 2969
1996 CHLOROBENZENE MR 2 SDWIS / WI7010114 / 2989
1996 Tetrachloroethylene MR 2 SDWIS / WI7010114 / 2987

How Preston Pines Compares

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

Metric Preston Pines Wisconsin avg Federal benchmark
Total violations 77 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 25.2% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 38 467 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 Preston Pines water safe to drink? ▼
Preston Pines (PWS ID: WI7010114) has 77 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 38 people using Groundwater sources.
How many people does Preston Pines serve? ▼
Preston Pines serves 38 people in Oconomowoc, Wisconsin. It is a Private-owned system using Groundwater water sources with 24 service connections.
What type of violations does Preston Pines have? ▼
Preston Pines has 77 total violations: 0 health-based violations (MCL exceedances or treatment failures), 64 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Preston Pines water? ▼
No PFAS testing data is available for Preston Pines under the EPA's UCMR5 monitoring program.
What water source does Preston Pines use? ▼
Preston Pines 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.