B79/100
Mount Vernon Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 15,793 residents · Illinois
What's In Mount Vernon'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 |
|---|---|---|---|
chlorate | 230.00 µg/L | — | Above Goal |
EPA Violation History
3
Violations (last 5yr)
0
Unresolved
0
Health-Related
TIER 3Resolved
Surface water treatment technique failure
When: July 1, 2024 – December 6, 2024Enforcement: 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: October 1, 2023 – December 31, 2023Rule: Stage 2 DBPREnforcement: 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: April 1, 2023 – June 30, 2023Rule: Stage 2 DBPREnforcement: 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
Water Utility Details
MOUNT VERNON
Population Served
15,793
Water Source
Purchased Surface Water
System ID
IL0810300
Frequently Asked Questions About Mount Vernon Water
Is Mount Vernon tap water safe to drink?
Mount Vernon, Illinois tap water receives a grade of B (79/100), which is considered good. 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 Mount Vernon's water?
Of the 69 contaminants tested in Mount Vernon's water supply, the most notable include chlorate. 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 Mount Vernon have any water quality violations?
Yes, Mount Vernon has 10 EPA violation(s) on record, with the most recent in 2024. Violation types include Other, MR, MCL. 2 of these are health-based violations, which are the most serious category.
Do I need a water filter in Mount Vernon?
Mount Vernon 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 Mount Vernon's tap water come from?
Mount Vernon's drinking water is sourced from purchased surface water and supplied by MOUNT VERNON. The system serves approximately 15,793 people. Surface water sources include rivers, lakes, and reservoirs.
How often is Mount Vernon'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. Mount Vernon'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 Mount Vernon's water compare to other cities in Illinois?
Mount Vernon's water quality score of 79/100 earns a grade of B, which is considered good. This is an above-average score compared to many cities nationwide. Visit our Illinois state page to see how all cities in the state compare.
What should I do if I'm concerned about Mount Vernon's water quality?
If you have concerns about Mount Vernon'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 (MOUNT VERNON) 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.