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Community Water System · PWS IL0974540

Island Lake

Island Lake, Illinois 60042 - drinking water served from groundwater sources to 8,066 people, tracked in EPA SDWIS and UCMR5.

8,066
People served
10
EPA violations
3
Health-based
No PFAS
UCMR5 result

The verdict

EPA records 10 drinking-water violations at Island Lake, 30% of them health-based - below the Illinois per-system average.

10
Total EPA violations on record
30%
Health-based (MCL / treatment failure)
8,066
People served by this system
0
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Island Lake

Island Lake is a local-owned community water system that delivers drinking water to 8,066 residents in Island Lake, Illinois (Lake County) through 3,103 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 10 total violations for this system , of which 3 (30%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 3 monitoring and reporting violations are on file. The most recent violation on record dates to 1997.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 3 violations (MR). This system was sampled under EPA's UCMR5 PFAS monitoring program and no PFAS compounds were detected above the minimum reporting level.

Across Illinois, EPA tracks 5,117 public water systems serving 12,576,876 people, with 355,322 cumulative violations and 52,932 health-based violations on record. About 81% of systems in the state carry at least one violation, and state-wide the average per system is 69.4 violations. Statewide, 199 of 487 UCMR5-tested systems have reported PFAS detections (40.9%).

Island Lake's 10 violations sit below the Illinois 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
8,066
Total Violations
10
Health-Based Violations
3
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
3,103
County
Lake
School/Daycare
No
MCL Violations
3
Monitoring Violations
3
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 3 1992
Coliform (TCR) MCL 3 1997

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 116 samples detected PFAS.

Contaminant Date Result MRL Status
9Cl-PF3ONS 5/8/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 5/8/2023 <5.00 ppt 5.00 ppt Not Detected
PFUnA 5/8/2023 <2.00 ppt 2.00 ppt Not Detected
4:2 FTS 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
ADONA 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 5/8/2023 <4.00 ppt 4.00 ppt Not Detected
PFBA 5/8/2023 <5.00 ppt 5.00 ppt Not Detected
PFDoA 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
PFDA 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
PFOA 5/8/2023 <4.00 ppt 4.00 ppt Not Detected
PFTA 5/8/2023 <8.00 ppt 8.00 ppt Not Detected
PFHxA 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpS 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 5/8/2023 <5.00 ppt 5.00 ppt Not Detected
PFHxS 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
PFTrDA 5/8/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 5/8/2023 <5.00 ppt 5.00 ppt Not Detected
PFOS 5/8/2023 <4.00 ppt 4.00 ppt Not Detected
PFBS 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 5/8/2023 <5.00 ppt 5.00 ppt Not Detected
PFPeS 5/8/2023 <4.00 ppt 4.00 ppt Not Detected
NFDHA 5/8/2023 <20.00 ppt 20.00 ppt Not Detected
PFEESA 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
PFMBA 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeA 5/8/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 5/8/2023 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 5/8/2023 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 5/8/2023 <6.00 ppt 6.00 ppt Not Detected
HFPO-DA 4/11/2023 <5.00 ppt 5.00 ppt Not Detected
PFUnA 4/11/2023 <2.00 ppt 2.00 ppt Not Detected
PFHpS 4/11/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeS 4/11/2023 <4.00 ppt 4.00 ppt Not Detected
NFDHA 4/11/2023 <20.00 ppt 20.00 ppt Not Detected
PFEESA 4/11/2023 <3.00 ppt 3.00 ppt Not Detected
PFMBA 4/11/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeA 4/11/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 4/11/2023 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 4/11/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 4/11/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 4/11/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 4/11/2023 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 4/11/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 4/11/2023 <5.00 ppt 5.00 ppt Not Detected
PFHxS 4/11/2023 <3.00 ppt 3.00 ppt Not Detected
PFTA 4/11/2023 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 4/11/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 4/11/2023 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 4/11/2023 <6.00 ppt 6.00 ppt Not Detected
ADONA 4/11/2023 <3.00 ppt 3.00 ppt Not Detected

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 Island Lake.

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 IL0974540 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Illinois Drinking Water Authority

Illinois EPA, Bureau of Water is the primacy agency that licenses and inspects Island Lake under EPA-delegated authority.

Open IL regulator portal

Source: Illinois EPA, Bureau of Water

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
1997 Coliform (TCR) MCL 3 SDWIS / IL0974540 / 3100
1992 Coliform (TCR) MR 3 SDWIS / IL0974540 / 3100

How Island Lake Compares

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

Metric Island Lake Illinois avg Federal benchmark
Total violations 10 69.4 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 3 10.3 Indicates a contaminant exceeded a federal MCL
PFAS detection None 40.9% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 8,066 2,458 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 5,117 regulated public water systems in Illinois.

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 Island Lake water safe to drink?
Island Lake (PWS ID: IL0974540) has 10 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 8,066 people using Groundwater sources.
How many people does Island Lake serve?
Island Lake serves 8,066 people in Island Lake, Illinois. It is a Local-owned system using Groundwater water sources with 3,103 service connections.
What type of violations does Island Lake have?
Island Lake has 10 total violations: 3 health-based violations (MCL exceedances or treatment failures), 3 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Island Lake water?
No. Island Lake was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does Island Lake use?
Island Lake 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. PFAS data from EPA UCMR5 monitoring program (2023-2025). This data is provided for informational purposes only.
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.