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Tap water quality report

Oak Park, IL

EPA monitoring detected 13 contaminants across the 1 water supplier serving Oak Park. 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
54,583
people served
13
contaminants found
Illinois rankings Lead in Illinois PFAS in Illinois

What was found in Oak Park'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
Copper
264 µg/L 20%
of the EPA limit 1300 µg/L
Main supplier: OAK PARK · 54,583 people · 2018
1/1 SYR4
TTHM
46.6 µg/L 58%
of the EPA limit 80 µg/L
Main supplier: OAK PARK · 54,583 people · 2019
1/1 SYR4
Chloroform
26.9 µg/L
No EPA limit set
Main supplier: OAK PARK · 54,583 people · 2019
1/1 SYR4
Total Haloacetic Acids (HAA5)
24.9 µg/L 42%
of the EPA limit 60 µg/L
Main supplier: OAK PARK · 54,583 people · 2019
1/1 SYR4
Lead
16.23 µg/L 108%
of the EPA limit, at the 95th percentile of samples — 15 µg/L
Main supplier: OAK PARK · 54,583 people · 2018
1/1 SYR4
Bromodichloromethane
13.6 µg/L
No EPA limit set
Main supplier: OAK PARK · 54,583 people · 2019
1/1 SYR4
Dichloroacetic Acid
11.9 µg/L
No EPA limit set
Main supplier: OAK PARK · 54,583 people · 2019
1/1 SYR4
Trichloroacetic Acid
10.6 µg/L
No EPA limit set
Main supplier: OAK PARK · 54,583 people · 2019
1/1 SYR4
Dibromochloromethane
6.69 µg/L
No EPA limit set
Main supplier: OAK PARK · 54,583 people · 2019
1/1 SYR4
Monochloroacetic Acid
4.9175 µg/L
No EPA limit set
Main supplier: OAK PARK · 54,583 people · 2019
1/1 SYR4
Monobromoacetic Acid
1.9105 µg/L
No EPA limit set
Main supplier: OAK PARK · 54,583 people · 2019
1/1 SYR4
Dibromoacetic Acid
1.674 µg/L
No EPA limit set
Main supplier: OAK PARK · 54,583 people · 2019
1/1 SYR4
Lead
0.0051 mg/L 34%
of the EPA limit 0.0150 mg/L
Main supplier: OAK PARK · 54,583 people · 2025
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 Oak Park

SupplierPopulation served
OAK PARK 54,583

Frequently asked questions about Oak Park tap water

Is Oak Park tap water safe to drink?

EPA testing detected 13 contaminants in the water serving Oak Park. 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 Oak Park?

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

What contaminants are in Oak Park's water?

The contaminants EPA monitoring detected in Oak Park include Copper, TTHM, Chloroform, Total Haloacetic Acids (HAA5), Lead. 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.