MATTESON: EPA violation history, explained

MATTESON has a health-based violation on record, but none in the last five years - an older issue, not necessarily a current one. It serves 18,293 people through 6,692 service connections.

MATTESON's record against the rest of the country

Out of 12,903 systems in this dataset, MATTESON ranks 7,929th by violation burden (39th percentile) - 16 violations total, 1 health-based.

How MATTESON compares within IL

Among the 560 IL systems in this dataset, the average is 5.0 health-based violations - MATTESON's 1 is at or below that. 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 MATTESON is from 2027-03-01 (health-based: 2005-01-09). Last reported to EPA: 05/27/2026.

What kind of problem, specifically

MATTESON'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 this data is and is not

MATTESON'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. This record - 1 health-based violation on file for MATTESON - stops at the meter and cannot see household plumbing on the other side of it. The guide to what this data misses covers that gap.