Is Green Oaks, IL Tap Water Safe to Drink?
Graded B-, with 7 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
73.8/100
waterverge.com Green Oaks, IL — Water Quality Report
Green Oaks's drinking water received a grade of B- (73.8 out of 100), indicating fair water quality. The city's 1 water system serves approximately 1,470 residents using purchased surface water.
Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.
The system has 11 violations on record, including 2 health-based violations. 7 remain unresolved.
What to know about Green Oaks's water
Green Oaks ranks #691 out of 891 cities in Illinois for water quality, placing it among the lowest-rated in the state.
The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.
As a small community water system, Green Oaks may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Green Oaks, IL water safe to drink?
Green Oaks's drinking water has significant quality concerns based on EPA testing data. With a grade of B- (73.8/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 1,470 residents using surface water (rivers, lakes, or reservoirs).
Recent water quality updates for Green Oaks
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Green Oaks's water quality assessment. Grade: B- (73.8/100).
Contaminants: Public Notice.
Contaminants: LEAD AND COPPER RULE REVISIONS, Consumer Confidence Rule.
1 health-based. Contaminants: LEAD AND COPPER RULE REVISIONS.
Federal disaster declaration (FEMA DR-4116). Flood event — may have impacted local water infrastructure.
Federal disaster declaration (FEMA DR-3230). Hurricane event — may have impacted local water infrastructure.
Key contaminant findings
Based on the most recent EPA sampling data for Green Oaks's water supply.
Well within EPA limits.
Violation history
Green Oaks's water system has 11 total violations on record, including 2 health-based violations. 7 remain unresolved. 5 violations were issued in the last 5 years.
Flood & environmental risk
Lake County has experienced 5 federally declared disasters since 1973. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Mill Creek, Des Plaines River, Buffalo Creek, North Branch Chicago River, Skokie River.
Where does Green Oaks's water come from?
Green Oaks's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 1 water system serving approximately 1,470 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Mill Creek (river), Des Plaines River (river), Buffalo Creek (river), North Branch Chicago River (river), Skokie River (river).
What Green Oaks residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Green Oaks's water.
Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.
Green Oaks's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Green Oaks
Industrial polluters nearby
Reported releases to surface water by facilities near Green Oaks, ranked by pounds discharged annually.
Total reported releases to surface water: 0 lbs
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
NORTHFIELD BLOCK CO MUNDELEIN, IL60060 | Lead | 0 | 5.4 mi |
THE IMAGINE GROUP LLC GRAYSLAKE, IL60030 | — | — | 7.1 mi |
HARGER INC. GRAYSLAKE, IL60030 | — | — | 7.0 mi |
GALLAGHER CORP GURNEE, IL60031 | — | — | 5.6 mi |
VANTAGE SPECIALTIES GURNEE, IL60031 | — | — | 5.8 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Superfund sites within 10 miles of Green Oaks
Superfund sites nearby
Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.
- OUTBOARD MARINE CORP6.4 mi
- YEOMAN CREEK LANDFILL6.9 mi
- JOHNS MANVILLE CORP7.8 mi
Source: EPA Superfund National Priorities List
Flood & disaster history
Lake County has experienced 5 federally declared disasters since 1973. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 0.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Green Oaks compares by contaminant
Explore where Green Oaks ranks among all Illinois cities for specific contaminants.
Water source & infrastructure
Where Green Oaks's water comes from
Green Oaks's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.
These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.
The system is operated by local government ownership and serves approximately 1,470 people through 1 water system.
Water bodies near Green Oaks
Green Oaks is located near 5 notable water bodies. As a surface water system, these water bodies may directly influence the city's drinking water supply.
Water systems serving Green Oaks
| System Name | PWSID | Population | Source |
|---|---|---|---|
| GREEN OAKS | IL0970040 | 1,470 | SWP |
How Green Oaks compares
Full Illinois rankings →Green Oaks's score of 73.8/100 is above the average of 56/100 among major Illinois cities. It outscores 7 of 10 nearby cities.
Nearby cities
View Illinois rankings →About Green Oaks, IL
Learn more about your water
Guides and resources related to Green Oaks's water quality findings.
Explore water quality across Lake
Frequently asked questions
Is Green Oaks, IL tap water safe to drink?
Green Oaks's water quality earned a grade of B- (73.8/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #691 out of 891 cities tested in Illinois.
What contaminants are in Green Oaks's water?
Lead was measured at 0.0 ppb (90th percentile). 11 violations are on record.
How is Green Oaks's water quality grade calculated?
The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.
Do I need a water filter in Green Oaks?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Green Oaks's water come from?
Green Oaks's water is sourced from Purchased surface water. The city has 1 water system serving approximately 1,470 residents.
What health violations has Green Oaks's water system had?
Green Oaks has 2 health-based violations on record. The most recent violation was recorded in August 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 7 violations remain unresolved.
How does Green Oaks's water compare to other cities?
Green Oaks ranks #691 out of 891 cities in Illinois (better than 22% of state cities) and #10018 out of 15744 cities nationally (36th percentile). The grade of B- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Green Oaks's small water system affect quality?
Green Oaks's system serves approximately 1,470 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 11 violations on record.