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Crystal Lake, IL Tap Water Quality 2026

Water quality report for Crystal Lake, IL — PFAS, lead and copper results, violation history and state inspection findings from EPA SDWIS.

A look at Crystal Lake's drinking water using EPA enforcement records: violations, lead and copper results, PFAS sampling and state inspection findings.

Main Utility: Crystal Lake PWSID: IL1110150 Updated: 2026 Q2
✅

No federal limits exceeded on record

Lead is 4.30 ppb, 29% of the action level and no violations are open. No PFAS was detected.

A

Crystal Lake earns an A for water quality

Graded on violations, lead, and PFAS, with state inspection findings.

Lead: 4.30 ppb — 29% of the federal action level
PFAS tested, none detected
12 violations since 2015, 0 health-based
No violations currently open
Crystal Lake's lead level vs. all Illinois community water systems
0 ppb5 ppb10 ppb15 ppb
Lead level: 4.30 ppb — 29% of the federal action level
✓ Lower lead than 36% of Illinois utilities
Population Served
39445
~14101 connections
Water Source
Groundwater
Drawn from wells — SDWIS source code GW
Active Violations
0
12 since 2015, all resolved

Lead & Copper Testing

Lead (Pb)
90th percentile of tap samples collected across the distribution system
29% of EPA action level
4.30 ppb
Action level: 15 ppb
The 90th-percentile lead result is 4.30 ppb, 29% of the 15 ppb federal action level. The action level is a treatment trigger, not a legal maximum, and it is measured across sampled taps rather than at any single home.

Contaminant Violations (2015–Present)

ContaminantTypeMeasuredLimitPeriodStatus
Atrazine MONITORING AND REPORTING — 0.003 mg/L 2026 Archived
Simazine MONITORING AND REPORTING — 0.004 mg/L 2026 Archived
LASSO MONITORING AND REPORTING — — 2026 Archived
HEXACHLOROBENZENE MONITORING AND REPORTING — 0.001 mg/L 2026 Archived
Di(2-ethylhexyl) phthalate MONITORING AND REPORTING — 0.006 mg/L 2026 Archived
BHC-GAMMA MONITORING AND REPORTING — 0.0002 mg/L 2026 Archived
Di(2-ethylhexyl) adipate MONITORING AND REPORTING — 0.4 mg/L 2026 Archived
Endrin MONITORING AND REPORTING — 0.002 mg/L 2026 Archived
Heptachlor MONITORING AND REPORTING — 0.0004 mg/L 2026 Archived
Hexachlorocyclopentadiene MONITORING AND REPORTING — 0.05 mg/L 2026 Archived
Heptachlor epoxide MONITORING AND REPORTING — 0.0002 mg/L 2026 Archived
Methoxychlor MONITORING AND REPORTING — 0.04 mg/L 2026 Archived
Understanding violation types MCL violations mean a contaminant exceeded the federal maximum limit — the most serious type.
TT (Treatment Technique) violations mean required treatment procedures weren't followed, but don't necessarily mean contamination occurred.

Violation History

12 violations are on record since 2015, of which 0 were health-based. All have been resolved and none remain open.

About the Main Water System

Utility Crystal Lake
PWSID IL1110150
Water source Groundwater — Drawn from wells — SDWIS source code GW
Population served 39,445
Service connections 14,101
Systems serving this area 10
Regulator State primacy agency
Data through 2026 Q2 — EPA SDWIS

Frequently Asked Questions

Is Crystal Lake tap water safe to drink? ▼
No federal limit is exceeded on record. No violations are currently open. Lead is 4.30 ppb, 29% of the action level.
Does Crystal Lake water have PFAS? ▼
It was tested for the six regulated PFAS compounds and none were detected.
Who supplies water to Crystal Lake? ▼
Crystal Lake (PWSID IL1110150), one of 10 systems serving this area. Groundwater. Drawn from wells — SDWIS source code GW
When was this system last inspected? ▼
It was last inspected on 2025-01-21. No significant deficiencies were recorded.

What Should Crystal Lake Residents Do?

1
Read your annual water report
Your supplier publishes a Consumer Confidence Report each July covering the prior year.
2
Check for a lead service line
Lead reaches tap water mainly through service lines and household plumbing. Suppliers now publish an inventory identifying lead lines.
3
Flush before drinking
If water has sat in pipes more than six hours, run the cold tap for two minutes before drinking or cooking.

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