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Community Water System · PWS IL0974080

Barrington

Barrington, Illinois 60010 - drinking water served from groundwater sources to 10,327 people, tracked in EPA SDWIS and UCMR5.

10,327
People served
16
EPA violations
1
Health-based
No PFAS
UCMR5 result

The verdict

EPA records 16 drinking-water violations at Barrington, 6% of them health-based - below the Illinois per-system average.

16
Total EPA violations on record
6%
Health-based (MCL / treatment failure)
10,327
People served by this system
0
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Barrington

Barrington is a local-owned community water system that delivers drinking water to 10,327 residents in Barrington, Illinois (Lake County) through 4,613 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 16 total violations for this system , of which 1 (6%) 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 1998.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 2 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%).

Barrington's 16 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
10,327
Total Violations
16
Health-Based Violations
1
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
4,613
County
Lake
School/Daycare
No
MCL Violations
0
Monitoring Violations
3
Treatment Tech Violations
1

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 2 1998
Lead and Copper Rule TT 1 1993
Gross Alpha, Excl. Radon and U MR 1 1977

PFAS Testing Results (UCMR5)

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

Contaminant Date Result MRL Status
PFHxS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
NEtFOSAA 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 8/15/2023 <6.00 ppt 6.00 ppt Not Detected
PFDA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFOA 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
PFNA 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
PFHpA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFBS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFOS 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
6:2 FTS 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 8/15/2023 <7.00 ppt 7.00 ppt Not Detected
PFHpS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeS 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
NFDHA 8/15/2023 <20.00 ppt 20.00 ppt Not Detected
PFEESA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFMBA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
9Cl-PF3ONS 8/15/2023 <2.00 ppt 2.00 ppt Not Detected
4:2 FTS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFDoA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFBA 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
PFTA 8/15/2023 <8.00 ppt 8.00 ppt Not Detected
ADONA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
11Cl-PF3OUdS 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
PFUnA 8/15/2023 <2.00 ppt 2.00 ppt Not Detected
PFHxA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
NEtFOSAA 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 8/15/2023 <7.00 ppt 7.00 ppt Not Detected
PFTA 8/15/2023 <8.00 ppt 8.00 ppt Not Detected
PFDA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFBS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 8/15/2023 <2.00 ppt 2.00 ppt Not Detected
PFOA 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
PFNA 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
PFDoA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
NMeFOSAA 8/15/2023 <6.00 ppt 6.00 ppt Not Detected
11Cl-PF3OUdS 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 8/15/2023 <2.00 ppt 2.00 ppt Not Detected
ADONA 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 8/15/2023 <5.00 ppt 5.00 ppt Not Detected
PFPeS 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 8/15/2023 <4.00 ppt 4.00 ppt Not Detected
PFHpS 8/15/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 8/15/2023 <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 Barrington.

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 IL0974080 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 Barrington 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
1998 Coliform (TCR) MR 2 SDWIS / IL0974080 / 3100
1993 Lead and Copper Rule TT 1 SDWIS / IL0974080 / 5000
1977 Gross Alpha, Excl. Radon and U MR 1 SDWIS / IL0974080 / 4000

How Barrington Compares

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

Metric Barrington Illinois avg Federal benchmark
Total violations 16 69.4 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 1 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 10,327 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 Barrington water safe to drink? ▼
Barrington (PWS ID: IL0974080) has 16 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 10,327 people using Groundwater sources.
How many people does Barrington serve? ▼
Barrington serves 10,327 people in Barrington, Illinois. It is a Local-owned system using Groundwater water sources with 4,613 service connections.
What type of violations does Barrington have? ▼
Barrington has 16 total violations: 1 health-based violations (MCL exceedances or treatment failures), 3 monitoring/reporting violations, and 1 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Barrington water? ▼
No. Barrington was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does Barrington use? ▼
Barrington 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.