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Tap water quality report

Eureka, IL

EPA monitoring detected 19 contaminants across the 3 water suppliers serving Eureka. 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.

3
water suppliers
10,439
people served
19
contaminants found
Illinois rankings Lead in Illinois PFAS in Illinois

What was found in Eureka'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
750.5 µg/L 58%
of the EPA limit 1300 µg/L
Main supplier: EUREKA · 5,216 people · 2017
Highest in the city: 1150 µg/L — CATERPILLAR TRAIL PWD · 5,125 people · 2019
3/3 SYR4
Fluoride
1050.1 µg/L 26%
of the EPA limit 4000 µg/L
Main supplier: EUREKA · 5,216 people · 2017
2/3 SYR4
Nitrate
660 µg/L 6.6%
of the EPA limit 10000 µg/L
Main supplier: EUREKA · 5,216 people · 2019
2/3 SYR4
Nitrate-Nitrite
515 µg/L 5.1%
of the EPA limit 10000 µg/L
Main supplier: EUREKA · 5,216 people · 2018
2/3 SYR4
Lead
182.855 µg/L 1219%
of the EPA limit, at the 95th percentile of samples — 15 µg/L
Main supplier: EUREKA · 5,216 people · 2017
2/3 SYR4
Nitrite
180 µg/L 18%
of the EPA limit 1000 µg/L
Main supplier: EUREKA · 5,216 people · 2018
1/3 SYR4
Barium
9.71 µg/L 0.5%
of the EPA limit 2000 µg/L
Main supplier: EUREKA · 5,216 people · 2017
Highest in the city: 17.19 µg/L — CATERPILLAR TRAIL PWD · 5,125 people · 2018
2/3 SYR4
Total Haloacetic Acids (HAA5)
14.576 µg/L 24%
of the EPA limit 60 µg/L
Main supplier: EUREKA · 5,216 people · 2019
2/3 SYR4
TTHM
12.5625 µg/L 16%
of the EPA limit 80 µg/L
Main supplier: EUREKA · 5,216 people · 2019
2/3 SYR4
Chloroform
10.473 µg/L
No EPA limit set
Main supplier: EUREKA · 5,216 people · 2019
2/3 SYR4
Dibromoacetic Acid
6.81 µg/L
No EPA limit set
Main supplier: EUREKA · 5,216 people · 2019
1/3 SYR4
Dichloroacetic Acid
5.341 µg/L
No EPA limit set
Main supplier: EUREKA · 5,216 people · 2019
2/3 SYR4
Trichloroacetic Acid
3.008 µg/L
No EPA limit set
Main supplier: EUREKA · 5,216 people · 2019
1/3 SYR4
Arsenic
2.36 µg/L 24%
of the EPA limit 10 µg/L
Main supplier: EUREKA · 5,216 people · 2017
1/3 SYR4
Monochloroacetic Acid
2.26 µg/L
No EPA limit set
Main supplier: EUREKA · 5,216 people · 2019
1/3 SYR4
Bromodichloromethane
2.085 µg/L
No EPA limit set
Main supplier: EUREKA · 5,216 people · 2019
1/3 SYR4
Monobromoacetic Acid
1.64 µg/L
No EPA limit set
Highest in the city: CATERPILLAR TRAIL PWD · 5,125 people · 2019
1/3 SYR4
Combined Radium (-226 And -228)
1.015 pCi/L 20%
of the EPA limit 5 pCi/L
Main supplier: EUREKA · 5,216 people · 2015
Highest in the city: 1.34 pCi/L — CATERPILLAR TRAIL PWD · 5,125 people · 2012
2/3 SYR4
Lead
0.0039 mg/L 26%
of the EPA limit 0.0150 mg/L
Main supplier: EUREKA · 5,216 people · 2025
Highest in the city: 0.0130 mg/L — CATERPILLAR TRAIL PWD · 5,125 people · 2025
3/3 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 Eureka

SupplierPopulation served
EUREKA 5,216
CATERPILLAR TRAIL PWD 5,125
TUCKAWAY PEORIA LLC 98

Frequently asked questions about Eureka tap water

Is Eureka tap water safe to drink?

EPA testing detected 19 contaminants in the water serving Eureka. 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 Eureka?

3 public water suppliers report drinking-water monitoring for Eureka, Illinois to the EPA. Each is listed above with its population served.

What contaminants are in Eureka's water?

The contaminants EPA monitoring detected in Eureka include Copper, Fluoride, Nitrate, Nitrate-Nitrite, 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.