Is Johnsburg, IL Tap Water Safe to Drink?
Graded B-, with 23 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
73.7/100
waterverge.com Johnsburg, IL — Water Quality Report
Johnsburg's drinking water received a grade of B- (73.7 out of 100), indicating fair water quality. The city's 2 water systems serve approximately 1,298 residents using groundwater.
Lead levels were measured at 1.3 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 78 violations on record, including 5 health-based violations. 23 remain unresolved.
What to know about Johnsburg's water
Johnsburg ranks #695 out of 891 cities in Illinois for water quality, placing it among the lowest-rated in the state.
Johnsburg 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, Johnsburg may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
The system has seen 8 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
Water quality score
See methodology →Is Johnsburg, IL water safe to drink?
Johnsburg's drinking water has significant quality concerns based on EPA testing data. With a grade of B- (73.7/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 2 water systems serve approximately 1,298 residents using groundwater (wells).
Recent water quality updates for Johnsburg
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Johnsburg's water quality assessment. Grade: B- (73.7/100).
Contaminants: Public Notice, Lead and Copper Rule.
Contaminants: Lead and Copper Rule.
Contaminants: Consumer Confidence Rule.
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 Johnsburg's water supply.
Well within EPA limits.
Violation history
Johnsburg's water system has 78 total violations on record, including 5 health-based violations. 23 remain unresolved. 8 violations were issued in the last 5 years.
Flood & environmental risk
McHenry County has experienced 6 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 Channel Lake, Fox Lake, Nippersink Lake, Nippersink Creek Above Wonder Lake, Elizabeth Lake Drain Nr Twin Lakes, Wi-Il.
Where does Johnsburg's water come from?
Johnsburg's drinking water comes from groundwater (wells), supplied by 2 water systems serving approximately 1,298 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Channel Lake (lake), Fox Lake (lake), Nippersink Lake (lake), Nippersink Creek Above Wonder Lake (river), Elizabeth Lake Drain Nr Twin Lakes, Wi-Il (river).
What Johnsburg residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Johnsburg'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.
Johnsburg'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 Johnsburg
Industrial polluters nearby
Reported releases to surface water by facilities near Johnsburg, ranked by pounds discharged annually.
Total reported releases to surface water: 9 lbs
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
SCOT FORGE CO SPRING GROVE, IL60081 | Nickel | 9 | 4.1 mi |
MATHEWS CO CRYSTAL LAKE, IL60012 | — | — | 9.6 mi |
WERNER CO. CRYSTAL LAKE, IL60014 | — | — | 9.8 mi |
TC INDUSTRIES INC CRYSTAL LAKE, IL60012 | — | — | 7.7 mi |
OZINGA READY-MIX CONCRETE - MCHENRY MCHENRY, IL60050 | — | — | 3.9 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Superfund sites within 10 miles of Johnsburg
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 GRAVEL9.0 mi
Source: EPA Superfund National Priorities List
Flood & disaster history
McHenry County has experienced 6 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. | 1.3 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Johnsburg compares by contaminant
Explore where Johnsburg ranks among all Illinois cities for specific contaminants.
Water source & infrastructure
Where Johnsburg's water comes from
Johnsburg'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 local government ownership and serves approximately 1,298 people through 2 water systems.
Water bodies near Johnsburg
Johnsburg is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Johnsburg
| System Name | PWSID | Population | Source |
|---|---|---|---|
| JOHNSBURG NO.2 | IL1115080 | 1,124 | GW |
| JOHNSBURG 1 | IL1110040 | 174 | GW |
How Johnsburg compares
Full Illinois rankings →Johnsburg's score of 73.7/100 is above the average of 56/100 among major Illinois cities. It outscores 7 of 10 nearby cities.
Nearby cities
View Illinois rankings →About Johnsburg, IL
Wikipedia →Johnsburg is a village in McHenry County, Illinois, with a population of 6,355 as of the 2020 U.S. census.
Learn more about your water
Guides and resources related to Johnsburg's water quality findings.
Explore water quality across Mchenry
Frequently asked questions
Is Johnsburg, IL tap water safe to drink?
Johnsburg's water quality earned a grade of B- (73.7/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #695 out of 891 cities tested in Illinois.
What contaminants are in Johnsburg's water?
Lead was measured at 1.3 ppb (90th percentile). 78 violations are on record.
How is Johnsburg'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 Johnsburg?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Johnsburg's water come from?
Johnsburg's water is sourced from Groundwater. The city has 2 water systems serving approximately 1,298 residents.
What health violations has Johnsburg's water system had?
Johnsburg has 5 health-based violations on record. The most recent violation was recorded in October 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 23 violations remain unresolved.
Is Johnsburg's groundwater at risk of contamination?
Johnsburg 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 78 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 Johnsburg's water compare to other cities?
Johnsburg ranks #695 out of 891 cities in Illinois (better than 22% of state cities) and #10041 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.