WILLOWBROOK: EPA violation history, explained
WILLOWBROOK has a health-based violation on record, but none in the last five years - an older issue, not necessarily a current one. 9,000 people get their water from it, across 2,207 connections.
How this compares nationally
WILLOWBROOK has 13 violations on record in total, 1 of them health-based - ranking it 8,046th of 12,903 systems by violation count, the 38th percentile nationally.
How WILLOWBROOK compares within IL
Among the 560 IL systems in this dataset, the average is 5.0 health-based violations - WILLOWBROOK's 1 is at or below that. See the lead and copper guide for why lead counts differently.
Most recent violation on record
The last violation EPA has on record for WILLOWBROOK is from 2025-02-07 (health-based: 1985-06-12). Last reported to EPA: 05/27/2026.
What kind of problem, specifically
WILLOWBROOK'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)
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
Everything on this page is WILLOWBROOK's own reported record under the Safe Drinking Water Act - a regulatory filing, not a sample of your tap. Water quality can still change between the meter and the faucet - household plumbing sits outside what a record of 13 logged violations can see. The guide to what this data misses covers that gap.