What's in WINTHROP HARBOR's water?

WINTHROP HARBOR has a health-based violation on record, but none in the last five years - an older issue, not necessarily a current one. Population served: 6,565, over 2,172 connections.

Ranked against every other system in this dataset

41 total violations and 7 health-based ones put WINTHROP HARBOR at the 80th percentile nationally for violation burden, rank 2,632 of 12,903.

Against the IL average

Among the 560 IL systems in this dataset, the average is 5.0 health-based violations - WINTHROP HARBOR's 7 is above that. See the lead and copper guide for why lead counts differently.

Most recent violation on record

WINTHROP HARBOR's most recent violation on record is dated 2026-01-01, with the most recent health-based one dated 2007-01-09. Last reported to EPA: 05/27/2026.

The concern categories on record

WINTHROP HARBOR'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:

• Microbial contamination / treatment technique - flagged from: Coliform (TCR)

The most severe category on record is microbial contamination / treatment technique, which points toward a microbial-class filter if you want to address it directly.

What WINTHROP HARBOR's record does not cover

This is what WINTHROP HARBOR 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 WINTHROP HARBOR's customers' taps is household plumbing, invisible to a system-level record ranked 2,632th of 12,903 by violation count. The guide to what this data misses covers that gap.