C53/100
NILWOOD — Water Quality Report 2026
Serving 1,394 people · Illinois
Water Source
Purchased Surface Water
County
—
System ID
IL1170750
Violations
23
Contaminant Test Results
EPA Violation History
5
Violations (last 5yr)
0
Unresolved
0
Health-Related
TIER 3Resolved
Monitoring Violation
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: March 1, 2025 – March 31, 2025Rule: Total Coliform RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Failed Level 2 Assessment under Revised Total Coliform Rule
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: March 1, 2025 – March 31, 2025Rule: Stage 1 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved
Disinfection byproduct treatment technique failure
When: January 13, 2022 – March 28, 2022Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Disinfection byproduct treatment technique failure
When: January 13, 2022 – March 28, 2022Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 3Resolved
Monitoring / Reporting Violation
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: December 30, 2021 – May 6, 2022Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Frequently Asked Questions About NILWOOD
Is NILWOOD water safe to drink?
NILWOOD water receives a grade of C (53/100), which is considered fair. 0 contaminant(s) exceed EPA legal limits and 23 violation(s) are on record. Customers may want to consider using a water filter.
What contaminants has NILWOOD detected?
1 contaminants were tested in NILWOOD's water. No contaminants exceed EPA legal limits or health goals, indicating good water quality management.
Does NILWOOD have any EPA violations?
Yes, NILWOOD has 23 EPA violation(s) on record, with the most recent in 2025. Violation types include MON, MR, Other. 6 are health-based violations.
How many people does NILWOOD serve?
NILWOOD serves approximately 1,394 people, Illinois. The system provides water to 1 community: Nilwood.
What type of water does NILWOOD provide?
NILWOOD sources its water from purchased surface water. Surface water comes from rivers, lakes, or reservoirs and typically requires more extensive treatment. The utility's system ID is IL1170750.
How does NILWOOD compare to other utilities in Illinois?
NILWOOD scores 53/100 with a grade of C (fair). This score indicates room for improvement compared to other utilities. Visit our Illinois state page for a full comparison of water systems.