B79/100
MACKINAW — Water Quality Report 2026
Serving 3,399 people · Illinois
Water Source
Groundwater
County
—
System ID
IL1790350
Violations
6
Contaminant Test Results
2 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 1.80 mg/L | 1.30 mg/L | Over Limit |
Lead (90th percentile) | 0.010 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
No violations in the past 5 years
Full EPA compliance since 2005.
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 MACKINAW
Is MACKINAW water safe to drink?
MACKINAW water receives a grade of B (79/100), which is considered good. Out of 32 contaminants tested, 1 exceed EPA legal limits. 2 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has MACKINAW detected?
32 contaminants were tested in MACKINAW's water. Notable contaminants include Copper (90th percentile), Lead (90th percentile). 1 exceed EPA legal limits (MCLs). 2 exceed EPA health goals (MCLGs).
Does MACKINAW have any EPA violations?
Yes, MACKINAW has 6 EPA violation(s) on record, with the most recent in 2005. Violation types include MR, MCL. 1 are health-based violations.
How many people does MACKINAW serve?
MACKINAW serves approximately 3,399 people, Illinois.
What type of water does MACKINAW provide?
MACKINAW sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is IL1790350.
How does MACKINAW compare to other utilities in Illinois?
MACKINAW scores 79/100 with a grade of B (good). This is an above-average performance for utilities statewide. Visit our Illinois state page for a full comparison of water systems.