Is Mount Carroll, IL Tap Water Safe to Drink?
Graded A, with 3 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓
92.7/100
waterverge.com Mount Carroll, IL — Water Quality Report
Mount Carroll's drinking water received a grade of A (92.7 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 1,479 residents using groundwater.
Lead levels were measured at 1.1 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 21 violations on record, including 8 health-based violations. 3 remain unresolved.
What to know about Mount Carroll's water
Mount Carroll ranks #62 out of 891 cities in Illinois for water quality, placing it one of the best in the state.
Mount Carroll 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, Mount Carroll may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Mount Carroll, IL water safe to drink?
Mount Carroll's drinking water has significant quality concerns based on EPA testing data. With a grade of A (92.7/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 1,479 residents using groundwater (wells).
Recent water quality updates for Mount Carroll
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Mount Carroll's water quality assessment. Grade: A (92.7/100).
Federal disaster declaration (FEMA DR-4461). Flood event — may have impacted local water infrastructure.
Contaminants: Combined Radium (-226 and -228).
Federal disaster declaration (FEMA DR-4116). Flood event — may have impacted local water infrastructure.
1 health-based. Contaminants: Combined Radium (-226 and -228).
1 health-based. Contaminants: Public Notice, Combined Radium (-226 and -228).
Key contaminant findings
Based on the most recent EPA sampling data for Mount Carroll's water supply.
Well within EPA limits.
Violation history
Mount Carroll's water system has 21 total violations on record, including 8 health-based violations. 3 remain unresolved.
Flood & environmental risk
Carroll County has experienced 8 federally declared disasters since 1969. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies.
Where does Mount Carroll's water come from?
Mount Carroll's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 1,479 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate.
What Mount Carroll residents can do
Recommended: NSF-certified water filter. This addresses the specific contaminants found in Mount Carroll'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.
Mount Carroll'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 Mount Carroll
Industrial polluters nearby
Reported releases to surface water by facilities near Mount Carroll, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
ELKAY PLUMBING PRODUCTS CO LANARK, IL61046 | — | — | 7.6 mi |
METFORM LLC MOUNT CARROLL, IL61053 | — | — | 0.7 mi |
ELKAY PLUMBING PRODUCTS CO SAVANNA, IL61074 | — | — | 7.2 mi |
METFORM CORP EXTRUSION SCIENCE PRODUCTS SAVANNA, IL61074 | — | — | 7.3 mi |
METFORM L.L.C. HOT FORMED PRODUCTS PLANT SAVANNA, IL61074 | — | — | 8.0 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Flood & disaster history
Carroll County has experienced 8 federally declared disasters since 1969. 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. | 1.1 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Mount Carroll compares by contaminant
Explore where Mount Carroll ranks among all Illinois cities for specific contaminants.
Water source & infrastructure
Where Mount Carroll's water comes from
Mount Carroll'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 1,479 people through 1 water system.
Water systems serving Mount Carroll
| System Name | PWSID | Population | Source |
|---|---|---|---|
| MOUNT CARROLL | IL0150200 | 1,479 | GW |
How Mount Carroll compares
Full Illinois rankings →Mount Carroll's score of 92.7/100 is above the average of 56/100 among major Illinois cities. It outscores 10 of 10 nearby cities.
Nearby cities
View Illinois rankings →About Mount Carroll, IL
Learn more about your water
Guides and resources related to Mount Carroll's water quality findings.
Explore water quality across Carroll
Frequently asked questions
Is Mount Carroll, IL tap water safe to drink?
Mount Carroll's water quality earned a grade of A (92.7/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #62 out of 891 cities tested in Illinois.
What contaminants are in Mount Carroll's water?
Lead was measured at 1.1 ppb (90th percentile). 21 violations are on record.
How is Mount Carroll'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 Mount Carroll?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Mount Carroll's water come from?
Mount Carroll's water is sourced from Groundwater. The city has 1 water system serving approximately 1,479 residents.
What health violations has Mount Carroll's water system had?
Mount Carroll has 8 health-based violations on record. The most recent violation was recorded in July 2019. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 3 violations remain unresolved.
Is Mount Carroll's groundwater at risk of contamination?
Mount Carroll 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 21 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 Mount Carroll's water compare to other cities?
Mount Carroll ranks #62 out of 891 cities in Illinois (better than 93% of state cities) and #1146 out of 15744 cities nationally (93th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Mount Carroll's small water system affect quality?
Mount Carroll's system serves approximately 1,479 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 21 violations on record.