Tap WaterIndex

← Illinois

Tap water quality report

Cahokia Heights

EPA monitoring tested this supplier for 31 contaminants and detected 5. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

31
contaminants tested
5
detected
12,528
people served
0
health-based violations
Illinois rankingsLead in IllinoisPFAS in Illinois
Water source
SWP
Ownership
Local government
Counties served
St. Clair

Compliance record

No violations on file. The EPA has no formal drinking-water violations recorded for this supplier.

PFAS detected

PFAS are industrial “forever chemicals”. These are the EPA's latest nationwide test results (2023–2025).
ContaminantMaxDetection ratePeriod
Pfba 0.0148 µg/L 4/4 2024
Pfpea 0.0031 µg/L 2/4 2024
Pfhxa 0.0036 µg/L 1/4 2024

Other contaminants detected

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 single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 7/7 LCR 2025
Lithium
21.8 µg/L
No EPA limit set
 2/4 UCMR-5 2024
26 contaminants tested, none detected
11Cl-PF3OUdS4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaHfpo-DaNetfosaaNfdhaNmefosaaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpesPftaPftrdaPfuna

Utility contact

Contact
SWANSON, JANAE'
Phone
618-515-2376
Email
jswanson@cahokiaillinois.org

Frequently asked questions about Cahokia Heights

Is Cahokia Heights tap water safe to drink?

EPA monitoring detected 5 contaminants in Cahokia Heights's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in Cahokia Heights's water?

EPA monitoring detected Lead, Pfba, Pfpea, Lithium, Pfhxa. The full list with the level and data source for each is above.

How many people does Cahokia Heights serve?

Cahokia Heights reports serving 12,528 people in Illinois, per its EPA record.

Has Cahokia Heights had any water quality violations?

The EPA has no formal drinking-water violations on file for Cahokia Heights.

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.