C58/100
Northbrook Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 42,671 residents · Illinois
What's In Northbrook's Tap Water?
69
Contaminants Tested
1
Exceed EPA Limits
0
Above EPA Goals
1 contaminant above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Lead (90th percentile) | 0.016 mg/L | 0.015 mg/L | Over Limit |
EPA Violation History
1
Violation (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: July 1, 2023 – September 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
SUNSET MHP
Population Served
1,400
Water Source
Purchased Surface Water
System ID
IL0310080
OASIS MHP
Population Served
3,000
Water Source
Groundwater
System ID
IL0315185
NORTHBROOK
Population Served
34,407
Water Source
Surface Water
System ID
IL0312070
MISSION BROOK SD
Population Served
2,852
Water Source
Purchased Surface Water
System ID
IL0315920
OAKBROOK ESTATES MHP
Population Served
1,012
Water Source
Purchased Groundwater
System ID
IL1115125
Frequently Asked Questions About Northbrook Water
Is Northbrook tap water safe to drink?
Northbrook, Illinois tap water receives a grade of C (58/100), which is considered fair. 1 contaminant(s) exceed EPA maximum contaminant levels and 99 violation(s) are on record. Residents should consider using an NSF-certified water filter to reduce contaminant exposure.
What contaminants are in Northbrook's water?
Of the 69 contaminants tested in Northbrook's water supply, the most notable include Lead (90th percentile). 1 contaminant(s) exceed EPA legal limits (MCLs). 1 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Northbrook have any water quality violations?
Yes, Northbrook has 99 EPA violation(s) on record, with the most recent in 2025. Violation types include RPT, MR, Other. 47 of these are health-based violations, which are the most serious category.
Do I need a water filter in Northbrook?
Based on EPA data, using a water filter in Northbrook is recommended. 1 contaminant(s) exceed legal limits. An NSF-certified filter — such as a reverse osmosis or activated carbon system — can effectively reduce many common contaminants. Choose a filter certified to remove the specific contaminants found in your area.
Where does Northbrook's tap water come from?
Northbrook's drinking water is sourced from purchased surface water and supplied by SUNSET MHP and 4 other water system(s). The system serves approximately 42,671 people. Surface water sources include rivers, lakes, and reservoirs.
How often is Northbrook'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. Northbrook'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 Northbrook's water compare to other cities in Illinois?
Northbrook's water quality score of 58/100 earns a grade of C, which is considered fair. This is a below-average score that indicates room for improvement. Visit our Illinois state page to see how all cities in the state compare.
What should I do if I'm concerned about Northbrook's water quality?
If you have concerns about Northbrook'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 (SUNSET MHP) 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.