A83/100
JOHNSTON CITY — Water Quality Report 2026
Serving 3,509 people · Illinois
Water Source
Purchased Surface Water
County
—
System ID
IL1990500
Violations
9
Contaminant Test Results
EPA Violation History
4
Violations (last 5yr)
2
Unresolved
1
Health-Related
TIER 3Resolved
Disinfection byproduct treatment technique failure
When: August 22, 2025 – September 19, 2025Rule: Ground Water RuleEnforcement: Resolving — corrective action underway
TIER 3Unresolved
Failed to issue ongoing public notification
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: July 1, 2025Rule: Ground Water RuleEnforcement: Informal — resolved cooperativelyVerify on EPA.gov
TIER 2Unresolved
Treatment technique violation
When: October 17, 2024Rule: Ground Water RuleEnforcement: Informal — resolved cooperativelyVerify on EPA.gov
TIER 3Resolved
Surface water treatment technique failure
When: July 1, 2024 – November 1, 2024Enforcement: 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 JOHNSTON CITY
Is JOHNSTON CITY water safe to drink?
JOHNSTON CITY water receives a grade of A (83/100), which is considered excellent. Out of 38 contaminants tested, none exceed EPA legal limits. The water meets federal safety standards.
What contaminants has JOHNSTON CITY detected?
38 contaminants were tested in JOHNSTON CITY's water. No contaminants exceed EPA legal limits or health goals, indicating good water quality management.
Does JOHNSTON CITY have any EPA violations?
Yes, JOHNSTON CITY has 9 EPA violation(s) on record, with the most recent in 2025. Violation types include Other, MR, TT. 2 are health-based violations.
How many people does JOHNSTON CITY serve?
JOHNSTON CITY serves approximately 3,509 people, Illinois. The system provides water to 1 community: Johnston City.
What type of water does JOHNSTON CITY provide?
JOHNSTON CITY 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 IL1990500.
How does JOHNSTON CITY compare to other utilities in Illinois?
JOHNSTON CITY scores 83/100 with a grade of A (excellent). This places it among the higher-performing utilities in the state. Visit our Illinois state page for a full comparison of water systems.