NORTHBROOK: EPA violation history, explained
NORTHBROOK has a health-based violation on record, but none in the last five years - an older issue, not necessarily a current one. Population served: 34,407, over 12,740 connections.
Ranked against every other system in this dataset
NORTHBROOK has 6 violations on record in total, 1 of them health-based - ranking it 8,534th of 12,903 systems by violation count, the 34th percentile nationally.
Against the IL average
NORTHBROOK's 1 health-based violations sit within the IL average of 5.0, across 560 systems statewide. See the lead and copper guide for why lead counts differently.
Most recent violation on record
NORTHBROOK's most recent violation on record is dated 2023-01-07, with the most recent health-based one dated 1993-01-01. Last reported to EPA: 05/27/2026.
The concern categories on record
NORTHBROOK'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:
- Lead & copper - flagged from: Lead and Copper Rule
The most severe category on record is lead & copper, which points toward a lead-class filter if you want to address it directly.
What NORTHBROOK's record does not cover
This is what NORTHBROOK reported to its state primacy agency and EPA under the Safe Drinking Water Act - real regulatory record, not a lab test of your specific tap. Between the utility's meter and NORTHBROOK's customers' taps is household plumbing, invisible to a system-level record ranked 8,534th of 12,903 by violation count. The guide to what this data misses covers that gap.