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Community Water System · PWS IL1110200

Fox River Grove

Fox River Grove, Illinois 60021 - drinking water served from groundwater sources to 4,702 people, tracked in EPA SDWIS and UCMR5.

4,702
People served
51
EPA violations
30
Health-based
4 PFAS
UCMR5 result

The verdict

EPA records 51 drinking-water violations at Fox River Grove, 59% of them health-based - below the Illinois per-system average, and UCMR5 testing detected 4 PFAS compounds.

51
Total EPA violations on record
59%
Health-based (MCL / treatment failure)
4,702
People served by this system
4
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Fox River Grove

Fox River Grove is a local-owned community water system that delivers drinking water to 4,702 residents in Fox River Grove, Illinois (McHenry County) through 1,642 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 51 total violations for this system , of which 30 (59%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 13 monitoring and reporting violations are on file. The most recent violation on record dates to 2020.

The most frequently cited contaminant at this system is Trichloroethylene, recorded in 17 violations (MCL, health-based). Under EPA's UCMR5 PFAS monitoring program, 4 PFAS compounds were detected in samples collected from this system, with a maximum reported concentration of 5.6 ppt (parts per trillion). PFAS are persistent synthetic chemicals linked to health effects at very low exposure levels.

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%).

Fox River Grove's 51 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.

PFAS Detected

4 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.

Population Served
4,702
Total Violations
51
Health-Based Violations
30
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
1,642
County
McHenry
School/Daycare
No
MCL Violations
19
Monitoring Violations
13
Treatment Tech Violations
11

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Trichloroethylene MCL 17 1992
Lead and Copper Rule TT 11 2020
Coliform (TCR) MR 6 1998
Lead and Copper Rule MR 4 2009
Coliform (TCR) MCL 2 2000
Total Haloacetic Acids (HAA5) MR 2 2004
Consumer Confidence Rule Other 2 2014
Gross Alpha, Excl. Radon and U MR 1 1977

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 5 of 116 samples detected PFAS.

Contaminant Date Result MRL Status
PFHpS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 9/12/2023 <2.00 ppt 2.00 ppt Not Detected
PFHxS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
PFPeS 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFTA 9/12/2023 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 9/12/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 9/12/2023 <6.00 ppt 6.00 ppt Not Detected
PFHpA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFDA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFDoA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 9/12/2023 3.70 ppt 3.00 ppt Detected
4:2 FTS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/12/2023 <20.00 ppt 20.00 ppt Not Detected
PFBS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 9/12/2023 <2.00 ppt 2.00 ppt Not Detected
PFPeA 9/12/2023 5.60 ppt 3.00 ppt Detected
PFEESA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
PFMBA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 9/12/2023 5.20 ppt 5.00 ppt Detected
ADONA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
11Cl-PF3OUdS 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
PFMPA 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFPeS 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
PFMPA 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFMBA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/12/2023 <20.00 ppt 20.00 ppt Not Detected
PFHpS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFTA 9/12/2023 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 9/12/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 9/12/2023 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 9/12/2023 <6.00 ppt 6.00 ppt Not Detected
PFPeA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFBS 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 9/12/2023 4.50 ppt 3.00 ppt Detected
PFNA 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 9/12/2023 <4.00 ppt 4.00 ppt Not Detected
PFDA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFDoA 9/12/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 9/12/2023 <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 Fox River Grove.

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 IL1110200 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 Fox River Grove 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
2020 Lead and Copper Rule TT 11 SDWIS / IL1110200 / 5000
2014 Consumer Confidence Rule Other 2 SDWIS / IL1110200 / 7000
2009 Lead and Copper Rule MR 4 SDWIS / IL1110200 / 5000
2004 Total Haloacetic Acids (HAA5) MR 2 SDWIS / IL1110200 / 2456
2000 Coliform (TCR) MCL 2 SDWIS / IL1110200 / 3100
1998 Coliform (TCR) MR 6 SDWIS / IL1110200 / 3100
1992 Trichloroethylene MCL 17 SDWIS / IL1110200 / 2984
1977 Gross Alpha, Excl. Radon and U MR 1 SDWIS / IL1110200 / 4000

How Fox River Grove Compares

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

Metric Fox River Grove Illinois avg Federal benchmark
Total violations 51 69.4 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 30 10.3 Indicates a contaminant exceeded a federal MCL
PFAS detection 4 compounds 40.9% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 4,702 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 Fox River Grove water safe to drink? ▼
Fox River Grove (PWS ID: IL1110200) has 51 recorded violations in the EPA SDWIS database. PFAS contamination has been detected in UCMR5 testing, with 4 PFAS compounds found. This system serves 4,702 people using Groundwater sources.
How many people does Fox River Grove serve? ▼
Fox River Grove serves 4,702 people in Fox River Grove, Illinois. It is a Local-owned system using Groundwater water sources with 1,642 service connections.
What type of violations does Fox River Grove have? ▼
Fox River Grove has 51 total violations: 30 health-based violations (MCL exceedances or treatment failures), 13 monitoring/reporting violations, and 11 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Fox River Grove water? ▼
Yes. UCMR5 testing detected 4 PFAS compounds in Fox River Grove's water supply: PFHxA, PFPeA, PFBA, PFHxS. PFAS are persistent "forever chemicals" that do not break down in the environment.
What water source does Fox River Grove use? ▼
Fox River Grove 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.

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.