Darien, IL Water Quality
What's in Darien's water?
Darien's only violations on record are reporting or monitoring lapses, not a contaminant or treatment-technique failure EPA classifies as health-based. 21,751 people get their water from it, across 8,944 connections.
Ranked against every other system in this dataset
3 total violations and 0 health-based ones put Darien at the 10th percentile nationally for violation burden, rank 11,590 of 12,903.
How Darien compares within IL
IL's 572 covered systems average 5.1 health-based violations each; Darien carries 0, not more than typical for the state. The filter guide explains what a violation like this actually calls for.
Most recent violation on record
The last violation EPA has on record for Darien is from 2024-01-07. Last reported to EPA: 05/27/2026.
What this data is and is not
Everything on this page is Darien'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 3 logged violations can see. The guide to what this data misses covers that gap.