Is Grayslake, IL Tap Water Safe to Drink?
Graded B+ — but Copper was detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓
80.9/100
waterverge.com Grayslake, IL — Water Quality Report
Grayslake's drinking water received a grade of B+ (80.9 out of 100), indicating good water quality. The city's 2 water systems serve approximately 2,642 residents using groundwater.
Lead levels were measured at 4.2 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 26 violations on record, including 7 health-based violations. 10 remain unresolved.
What to know about Grayslake's water
Grayslake ranks #537 out of 891 cities in Illinois for water quality, placing it below average in the state.
Grayslake relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.
As a small community water system, Grayslake may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Grayslake, IL water safe to drink?
Grayslake's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (80.9/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 2,642 residents using groundwater (wells).
Recent water quality updates for Grayslake
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Grayslake's water quality assessment. Grade: B+ (80.9/100).
Contaminants: Consumer Confidence Rule.
Contaminants: Consumer Confidence Rule.
Federal disaster declaration (FEMA DR-4116). Flood event — may have impacted local water infrastructure.
Contaminants: Consumer Confidence Rule.
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 Grayslake's water supply.
Well within EPA limits.
Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.
Violation history
Grayslake's water system has 26 total violations on record, including 7 health-based violations. 10 remain unresolved. 1 violation was 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 Des Plaines River, Mill Creek, Channel Lake, Fox Lake, Nippersink Lake.
Where does Grayslake's water come from?
Grayslake's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 2,642 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Des Plaines River (river), Mill Creek (river), Channel Lake (lake), Fox Lake (lake), Nippersink Lake (lake).
What Grayslake residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Grayslake'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.
Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.
Grayslake'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 Grayslake
Industrial polluters nearby
Reported releases to surface water by facilities near Grayslake, 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 | 7.2 mi |
SKACH MANUFACTURING CO. ANTIOCH, IL60002 | — | — | 9.9 mi |
THE IMAGINE GROUP LLC GRAYSLAKE, IL60030 | — | — | 0.5 mi |
HARGER INC. GRAYSLAKE, IL60030 | — | — | 0.6 mi |
GALLAGHER CORP GURNEE, IL60031 | — | — | 7.3 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Superfund sites within 10 miles of Grayslake
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.
- WAUCONDA SAND GRAVEL6.7 mi
- H O D LANDFILL9.6 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.
Recommended water filters
Based on contaminants detected in Grayslake's water supply, we recommend the following filter types.
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. | 4.2 | 15 | ppb | Inorganic | Safe |
| Copper (90th percentile) CopperInorganic A metal that enters drinking water mainly through corrosion of copper plumbing. Small amounts are essential for health, but excess levels are harmful. Health EffectsGastrointestinal distress (nausea, vomiting, diarrhea) at short-term high levels; liver and kidney damage from long-term exposure. EPA Limit1.3 mg/L action level Common SourcesCorrosion of copper household plumbing, erosion of natural deposits. | 2.38 | 1.3 | mg/L | Inorganic | Over Limit |
Lead level trend (90th percentile)
Copper level (90th percentile)
Latest reading: 2.380 mg/L (2003)
EPA action level: 1.3 mg/L
See how Grayslake compares by contaminant
Explore where Grayslake ranks among all Illinois cities for specific contaminants.
Water source & infrastructure
Where Grayslake's water comes from
Grayslake's drinking water is drawn from underground aquifers through wells.
Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.
Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.
The system is operated by private ownership and serves approximately 2,642 people through 2 water systems.
Water bodies near Grayslake
Grayslake is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Grayslake
| System Name | PWSID | Population | Source |
|---|---|---|---|
| SADDLEBROOK FARMS | IL0970120 | 2,558 | GW |
| CHAIN-O-LAKES MHP | IL0975165 | 84 | GW |
How Grayslake compares
Full Illinois rankings →Grayslake's score of 80.9/100 is above the average of 56/100 among major Illinois cities. It outscores 7 of 10 nearby cities.
Nearby cities
View Illinois rankings →About Grayslake, IL
Wikipedia →Grayslake is a village in Lake County, Illinois, United States. The village's population at the 2020 census was 21,248. It is located in the Chicago metropolitan area, about 40 miles (64 km) north of Chicago's downtown, 14 miles (23 km) west of Lake Michigan, and 15 miles (24 km) south of the Wisconsin border.
Learn more about your water
Guides and resources related to Grayslake's water quality findings.
Explore water quality across Lake
Frequently asked questions
Is Grayslake, IL tap water safe to drink?
Grayslake's water quality earned a grade of B+ (80.9/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #537 out of 891 cities tested in Illinois.
What contaminants are in Grayslake's water?
Lead was measured at 4.2 ppb (90th percentile). 26 violations are on record.
How is Grayslake'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 Grayslake?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Grayslake's water come from?
Grayslake's water is sourced from Groundwater. The city has 2 water systems serving approximately 2,642 residents.
What health violations has Grayslake's water system had?
Grayslake has 7 health-based violations on record. The most recent violation was recorded in July 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 10 violations remain unresolved.
Is Grayslake's groundwater at risk of contamination?
Grayslake uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 26 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.
How does Grayslake's water compare to other cities?
Grayslake ranks #537 out of 891 cities in Illinois (better than 40% of state cities) and #7665 out of 15744 cities nationally (51th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.