Is OAK BROOK's water safe to drink?
OAK BROOK has a health-based violation on record, but none in the last five years - an older issue, not necessarily a current one. Population served: 9,400, over 3,295 connections.
OAK BROOK's record against the rest of the country
Out of 12,903 systems in this dataset, OAK BROOK ranks 4,404th by violation burden (66th percentile) - 10 violations total, 4 health-baseds.
How OAK BROOK compares within IL
IL's 560 covered systems average 5.0 health-based violations each; OAK BROOK carries 4, not more than typical for the state. The clean-record guide covers what a comparison like this can hide.
Most recent violation on record
The last violation EPA has on record for OAK BROOK is from 2024-01-07 (health-based: 1989-01-10). Last reported to EPA: 05/27/2026.
What kind of problem, specifically
OAK BROOK's flagged contaminants and rule violations, grouped by what they actually mean for a filter choice rather than left as EPA's raw code list:
- Radionuclides - flagged from: Combined Radium (-226 and -228); Gross Alpha, Excl. Radon and U
The most severe category on record is radionuclides, which points toward a reverse osmosis-class filter if you want to address it directly.
What this data is and is not
OAK BROOK's numbers here come from its own required reporting to EPA under the Safe Drinking Water Act, not from an independent test of your glass of water. Water quality can still change between the meter and the faucet - household plumbing sits outside what a record of 10 logged violations can see. The guide to what this data misses covers that gap.