WaterVerge

Is Saint Charles, IL Tap Water Safe to Drink?

Graded B+ — but Strontium and Manganese were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

33K residents served 1 water system PWSID: IL0894830
Overall Score
83.4 / 100
Violations
3 active
Last Updated
May 2026
Source
Groundwater
#444 of 891 in Illinois Top 41% nationally
Local Government
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B+GRADE
Water Quality Grade
83.4/100
waterverge.com
B+ 83.4/100

Saint Charles, IL — Water Quality Report

Saint Charles's drinking water received a grade of B+ (83.4 out of 100), indicating good water quality. The city's 1 water system serves approximately 33,103 residents using groundwater.

Lead levels were measured at 6.5 ppb (90th percentile), which is within EPA limits but above recommended levels. UCMR 5 testing detected 2 PFAS compounds in the water supply.

The system has 10 violations on record, including 3 health-based violations. 3 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Saint Charles's water

Saint Charles ranks #444 out of 891 cities in Illinois for water quality, placing it mid-range in the state.

Saint Charles 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.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Hexavalent chromium (chromium-6) was detected at 0.07 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.

While lead levels are within EPA limits, they are above the recommended 5 ppb threshold that health organizations consider ideal. A point-of-use filter adds an extra layer of protection.

Quality Breakdown

Water quality score

See methodology →
83.4 out of 100 Grade B+
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
41.7/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
16/20
B
Lead at 6.5 ppb (90th percentile).
Contaminants
15.7/20
B
2 PFAS compounds detected.
Compliance
5/10
D
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Saint Charles, IL water safe to drink?

Concerns Identified

Saint Charles's drinking water has significant quality concerns based on EPA testing data. With a grade of B+ (83.4/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 1 water system serves approximately 33,103 residents using groundwater (wells).

3
Active Violations
6.5 ppb
Lead (90th %ile)
2 compounds
PFAS Detected
5 events
Disaster History

Recent water quality updates for Saint Charles

A timeline of significant water quality events, violations, and data updates.

PFAS
2 PFAS "forever chemical" compounds detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Saint Charles's water quality assessment. Grade: B+ (83.4/100).

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Violation
1 drinking water violation recorded

Contaminants: Combined Radium (-226 and -228).

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Disaster
SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING

Federal disaster declaration (FEMA DR-4116). Flood event — may have impacted local water infrastructure.

Key contaminant findings

Based on the most recent EPA sampling data for Saint Charles's water supply.

Lead Elevated
Detected: 6.5 ppb Limit: 15 ppb (EPA Action Level)

Within EPA limits but above the American Academy of Pediatrics recommended level of 1 ppb. An NSF 53-certified filter provides additional protection.

PFAS (2 compounds) Elevated
Detected: Highest: lithium at 28.6000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

PFAS "forever chemicals" detected

UCMR 5 testing found 2 PFAS compounds in Saint Charles's water supply. PFAS are synthetic chemicals that persist indefinitely in the environment and the human body.

Compound Level EPA MCL Status
lithium 28.6000 µg/L 0.004 µg/L Within Limit
PFBS 0.0043 µg/L 0.004 µg/L Within Limit

Violation history

Saint Charles's water system has 10 total violations on record, including 3 health-based violations. 3 remain unresolved. 1 violation was issued in the last 5 years.

OtherMRMCL
Most recent violations:
Jul 2025 Consumer Confidence Rule Open
Oct 2020 Combined Radium (-226 and -228) Resolved
Jul 2016 Consumer Confidence Rule Open
Jan 2002 Nitrate Resolved
Jul 1995 Coliform (TCR) Resolved

Flood & environmental risk

Kane 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 West Branch Du Page River, Kress Creek, Tyler Creek, Poplar Creek, Fox River.

SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING
Flood FEMA DR-4116
HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3230
SEVERE STORMS & FLOODING
Flood FEMA DR-776

Where does Saint Charles's water come from?

Saint Charles's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 33,103 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include West Branch Du Page River (river), Kress Creek (river), Tyler Creek (river), Poplar Creek (river), Fox River (river).

What Saint Charles residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Saint Charles's water.

Request your utility's CCR

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.

Flush your taps

Run cold water for 30 seconds before drinking, especially in the morning. Lead and copper leach from household plumbing when water sits in pipes.

Monitor alerts during storms

Saint Charles'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.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
6.5 ppb
EPA Action Level: 15 ppb · 43% of limit
Safe Level
lithium
PFAS / Forever Chemical
Near MCL
28.6000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
5.8 µg/L
EPA MCL: 60 µg/L · 10% of limit
Within LimitUCMR 4 DataHAA6Br: 5.1 µg/LHAA9: 9.3 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.07 µg/L
CA MCL (no federal MCL): 10 µg/L · 1% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Over HRL
3317.8 µg/L
EPA Health Ref Level: 1,500 µg/L · +20% over limit
Over HRLUCMR 3 Data
1,4-Dioxane
Organic
Detected
0.10 µg/L
EPA Health Advisory: 0.35 µg/L · 29% of limit
DetectedUCMR 3 Data
Manganese
Inorganic
Over SMCL
86.8 µg/L
EPA Secondary MCL: 50 µg/L · +20% over limit
Over SMCLUCMR 4 Data
Chlorate
Disinfection Byproduct
Elevated
210.0 µg/L
EPA Lifetime HA: 210 µg/L · +0% over limit
DetectedUCMR 3 Data
Molybdenum
Inorganic
Detected
2.60 µg/L
EPA Lifetime HA: 40 µg/L · 7% of limit
DetectedUCMR 3 Data
Lithium
Inorganic
Detected
28.6 µg/L
State screening level: 60 µg/L · 48% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
2
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

10
Total violations
3
Health-based
3
Active / unresolved
Jul 2025
Most recent violation
Compliance Record

Violations & advisories

10 Total
3 Active
3 Health-based
7 Resolved
Violations by category
Radionuclides and Revised Rad Rule
4
Consumer Confidence Rule
2
Total Coliform Rule
2
Nitrate Rule
1
Jul 2025 Active
Consumer Confidence Rule
Other Violation 0
Jul 2016 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Oct 2020 Resolved
Combined Radium (-226 and -228)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2020
Jan 2002 Resolved
Nitrate
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2002
Jul 1995 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Jul 1995
Jul 1995 Resolved
Coliform (TCR)
Max Contaminant Level
Health-Based Health Resolved Jul 1995
Jan 1991 Resolved
Gross Alpha, Excl. Radon and U
Max Contaminant Level
Health-Based Health Resolved Jan 1995
Jan 1991 Resolved
Combined Radium (-226 and -228)
Max Contaminant Level
Health-Based Health Resolved Jan 1995
Jun 1977 Resolved
Gross Alpha, Excl. Radon and U
Monitoring & Reporting
Monitoring & Reporting Resolved Jun 1981
Environmental Risk

Flood & disaster history

5
Declared disasters
May 2013
Most recent
Flood
Most common type

Kane 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.

May 2013
SEVERE STORMS, STRAIGHT-LINE WINDS, AND FLOODING
Flood FEMA #4116
Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3230
Oct 1986
SEVERE STORMS & FLOODING
Flood FEMA #776
Jun 1974
SEVERE STORMS & FLOODING
Flood FEMA #438
Apr 1973
SEVERE STORMS & FLOODING
Flood FEMA #373

Recommended water filters

Based on contaminants detected in Saint Charles's water supply, we recommend the following filter types.

🚰
For Lead
Reverse Osmosis or NSF 53-Certified Pitcher
Lead detected at 6.5 ppb
Read our guide →
🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
2 PFAS compounds detected

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 6.5 15 ppb Inorganic Safe
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium 28.600 HI µg/L PFAS Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS 0.004 HI µg/L PFAS Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 9.2 ppb from 1992 (12.0 ppb) to 2025 (2.8 ppb).
Contaminant Rankings

See how Saint Charles compares by contaminant

Explore where Saint Charles ranks among all Illinois cities for specific contaminants.

Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
Local Government
Population Served
33,103
Water Systems
1
Water Source

Where Saint Charles's water comes from

Groundwater

Saint Charles'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 33,103 people through 1 water system.

Local Hydrology

Water bodies near Saint Charles

Saint Charles is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

West Branch Du Page River
river
Kress Creek
river
Tyler Creek
river
Poplar Creek
river
Fox River
river
Infrastructure

Water systems serving Saint Charles

System Name PWSID Population Source
ST CHARLES IL0894830 33,103 GW
Regional Comparison

How Saint Charles compares

Full Illinois rankings →

Saint Charles's score of 83.4/100 is above the average of 56/100 among major Illinois cities. It outscores 9 of 10 nearby cities.

Saint Charles (this city)
83.4
Chicago
35.2
Aurora
45.5
Joliet
38.5
Naperville
81.2
Champaign
91.9
Illinois avg
56
City Profile

About Saint Charles, IL

Wikipedia →

St. Charles or Saint Charles is a city in Kane and DuPage Counties, Illinois, United States. The population was 33,081 at the 2020 census, and was estimated at 33,482 in 2024. It lies roughly 35 miles west of Chicago on Illinois Route 64. The official city slogan is "Pride of the Fox", after the Fox River that runs through the center of town. St. Charles is part of a tri-city area along with Geneva and Batavia, all western Chicago suburbs of similar size and socioeconomic condition.

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Frequently asked questions

Is Saint Charles, IL tap water safe to drink?

Saint Charles's water quality earned a grade of B+ (83.4/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #444 out of 891 cities tested in Illinois.

What contaminants are in Saint Charles's water?

Lead was measured at 6.5 ppb (90th percentile). 2 PFAS compounds were detected. 10 violations are on record.

How is Saint Charles'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 Saint Charles?

While lead levels are within EPA limits, a filter adds extra protection. PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Saint Charles's water come from?

Saint Charles's water is sourced from Groundwater. The city has 1 water system serving approximately 33,103 residents.

What health violations has Saint Charles's water system had?

Saint Charles has 3 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. 3 violations remain unresolved.

Is Saint Charles's groundwater at risk of contamination?

Saint Charles 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 10 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 Saint Charles's water compare to other cities?

Saint Charles ranks #444 out of 891 cities in Illinois (better than 50% of state cities) and #6432 out of 15744 cities nationally (59th percentile). The grade of B+ reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.