A87/100
Wilmette Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 27,087 residents · Illinois
What's In Wilmette's Tap Water?
69
Contaminants Tested
0
Exceed EPA Limits
1
Above EPA Goals
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | 0.007 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
1
Violation (last 5yr)
1
Unresolved
0
Health-Related
TIER 3Unresolved
Surface water treatment technique failure
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
Water Utility Details
WILMETTE
Population Served
27,087
Water Source
Surface Water
System ID
IL0313300
Frequently Asked Questions About Wilmette Water
Is Wilmette tap water safe to drink?
Wilmette, Illinois tap water receives a grade of A (87/100), which is considered excellent. Out of 69 contaminants tested, none exceed EPA maximum contaminant levels (MCLs) and 1 exceed health guidelines (MCLGs). While the water meets federal standards, some residents may still choose to use a filter for additional peace of mind.
What contaminants are in Wilmette's water?
Of the 69 contaminants tested in Wilmette's water supply, the most notable include Lead (90th percentile). No contaminants exceed EPA legal limits. 1 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Wilmette have any water quality violations?
Yes, Wilmette has 10 EPA violation(s) on record, with the most recent in 2025. Violation types include Other, MR. None of these are classified as health-based violations.
Do I need a water filter in Wilmette?
Wilmette water meets EPA standards, so a filter is not strictly necessary. However, some residents prefer the added security of a water filter. EPA health goals (MCLGs) are stricter than legal limits and are set at levels with zero expected health risk. 1 contaminant(s) exceed these stricter goals.
Where does Wilmette's tap water come from?
Wilmette's drinking water is sourced from surface water and supplied by WILMETTE. The system serves approximately 27,087 people. Surface water sources include rivers, lakes, and reservoirs.
How often is Wilmette's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Wilmette's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Wilmette's water compare to other cities in Illinois?
Wilmette's water quality score of 87/100 earns a grade of A, which is considered excellent. This places Wilmette among the better-performing water systems in Illinois. Visit our Illinois state page to see how all cities in the state compare.
What should I do if I'm concerned about Wilmette's water quality?
If you have concerns about Wilmette's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (WILMETTE) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.