F0/100
OSWEGO — Water Quality Report 2026
Serving 38,169 people · Illinois
Water Source
Groundwater
County
—
System ID
IL0930150
Violations
56
Contaminant Test Results
2 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
strontium | 2638.60 µg/L | — | Above Goal |
Lead (90th percentile) | 0.001 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
2
Violations (last 5yr)
0
Unresolved
0
Health-Related
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: September 1, 2024 – September 30, 2024Rule: Stage 1 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved
Surface water treatment technique failure
When: July 1, 2022 – June 9, 2023Enforcement: 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 OSWEGO
Is OSWEGO water safe to drink?
OSWEGO water receives a grade of F (0/100), which is considered failing. 0 contaminant(s) exceed EPA legal limits and 56 violation(s) are on record. Customers may want to consider using a water filter.
What contaminants has OSWEGO detected?
66 contaminants were tested in OSWEGO's water. Notable contaminants include Lead (90th percentile), strontium. No contaminants exceed EPA legal limits. 2 exceed EPA health goals (MCLGs).
Does OSWEGO have any EPA violations?
Yes, OSWEGO has 56 EPA violation(s) on record, with the most recent in 2024. Violation types include MR, Other, MCL. 24 are health-based violations.
How many people does OSWEGO serve?
OSWEGO serves approximately 38,169 people, Illinois. The system provides water to 1 community: Oswego.
What type of water does OSWEGO provide?
OSWEGO sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is IL0930150.
How does OSWEGO compare to other utilities in Illinois?
OSWEGO scores 0/100 with a grade of F (failing). This score suggests significant water quality concerns relative to other utilities. Visit our Illinois state page for a full comparison of water systems.