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Tap water quality report

Saint Charles, IL

EPA monitoring detected 26 contaminants across the 1 water supplier serving Saint Charles. A detection doesn't automatically mean the water is unsafe — see the level at the main supplier for each below, with its EPA source and period.

1
water supplier
33,103
people served
26
contaminants found
Illinois rankings Lead in Illinois PFAS in Illinois

What was found in Saint Charles's water

The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Barium
1190.5 µg/L 60%
of the EPA limit 2000 µg/L
Main supplier: ST CHARLES · 33,103 people · 2018
1/1 SYR4
Fluoride
1106 µg/L 28%
of the EPA limit 4000 µg/L
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Nitrate
613.5 µg/L 6.1%
of the EPA limit 10000 µg/L
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Nitrate-Nitrite
480.3 µg/L 4.8%
of the EPA limit 10000 µg/L
Main supplier: ST CHARLES · 33,103 people · 2018
1/1 SYR4
Copper
217 µg/L 17%
of the EPA limit 1300 µg/L
Main supplier: ST CHARLES · 33,103 people · 2017
1/1 SYR4
TTHM
31.05 µg/L 39%
of the EPA limit 80 µg/L
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Lithium
28.6 µg/L
No EPA limit set
Main supplier: ST CHARLES · 33,103 people · 2025
1/1 UCMR-5
Chloroform
23.8 µg/L
No EPA limit set
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Lead
18.36 µg/L 122%
of the EPA limit, at the 95th percentile of samples — 15 µg/L
Main supplier: ST CHARLES · 33,103 people · 2017
1/1 SYR4
Nitrite
12 µg/L 1.2%
of the EPA limit 1000 µg/L
Main supplier: ST CHARLES · 33,103 people · 2018
1/1 SYR4
Total Haloacetic Acids (HAA5)
11.275 µg/L 19%
of the EPA limit 60 µg/L
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Dibromochloromethane
9.172 µg/L
No EPA limit set
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Chromium
8 µg/L 8%
of the EPA limit 100 µg/L
Main supplier: ST CHARLES · 33,103 people · 2018
1/1 SYR4
Bromodichloromethane
7.0465 µg/L
No EPA limit set
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Monobromoacetic Acid
6.019 µg/L
No EPA limit set
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Selenium
5.2 µg/L 10%
of the EPA limit 50 µg/L
Main supplier: ST CHARLES · 33,103 people · 2018
1/1 SYR4
Dichloroacetic Acid
4.8355 µg/L
No EPA limit set
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Combined Radium (-226 And -228)
4.677 pCi/L 94%
of the EPA limit 5 pCi/L
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Bromoform
4.163 µg/L
No EPA limit set
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Dibromoacetic Acid
4.0625 µg/L
No EPA limit set
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Trichloroacetic Acid
2.295 µg/L
No EPA limit set
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Carbon Tetrachloride
1.5 µg/L 30%
of the EPA limit 5 µg/L
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
Arsenic
0.8115 µg/L 8.1%
of the EPA limit 10 µg/L
Main supplier: ST CHARLES · 33,103 people · 2018
1/1 SYR4
Benzo(A)Pyrene
0.1470 µg/L 73%
of the EPA limit 0.2000 µg/L
Main supplier: ST CHARLES · 33,103 people · 2019
1/1 SYR4
PFBS
0.0043 µg/L
No EPA limit set
Main supplier: ST CHARLES · 33,103 people · 2025
1/1 UCMR-5
Lead
0.0033 mg/L 22%
of the EPA limit 0.0150 mg/L
Main supplier: ST CHARLES · 33,103 people · 2026
1/1 LCR
Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of the system's samples — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately. These are the utilities' own EPA-reported results, not a city-wide average. A detection means the lab measured the substance — it isn't the same as exceeding a legal limit. Hover a source tag to see the EPA program and years behind each figure.

Water suppliers serving Saint Charles

SupplierPopulation served
ST CHARLES 33,103

Frequently asked questions about Saint Charles tap water

Is Saint Charles tap water safe to drink?

EPA testing detected 26 contaminants in the water serving Saint Charles. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.

How many water suppliers serve Saint Charles?

1 public water supplier report drinking-water monitoring for Saint Charles, Illinois to the EPA. Each is listed above with its population served.

What contaminants are in Saint Charles's water?

The contaminants EPA monitoring detected in Saint Charles include Barium, Fluoride, Nitrate, Nitrate-Nitrite, Copper. The full list, with the level at the main supplier and the data source, is in the table above.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.