EPA data as of Oct 2026 · page updated 2026-10-30

Dorchester

Dorchester (EPA ID IL1170250) in Dorchester, IL supplies surface water (rivers, lakes) to about 540 people: 1 violation since 2016, latest lead result 0 ppb, PFAS not tested.

Service area

EPA service-area boundary (state-supplied or EPA-modeled)
Water utility service area PFOA/PFOS ≥ 4 ppt Lead > 15 ppb 5+ violations Superfund site (active) proposed cleaned up Circles: other water systems flagged nearby; size = people served. Tap any symbol for details.

System facts

People served540
Connections219
Sourcesurface water (rivers, lakes)
WholesalerNo

Health-based violations

Contaminant or ruleHealth-based violations since 2016
Long Term 2 Enhanced Surface Water Treatment Rule1

A health-based violation means a contaminant exceeded its legal limit (MCL) or a required treatment technique was not met, as reported by the state to EPA’s SDWIS. All are listed as resolved or archived; the latest began Jan 2026.

Lead

Jan 20250 ppb
Jan 20230 ppb
Jan 20225.9 ppb
Jan 20170 ppb
Jan 20140 ppb
Jan 20110 ppb
Jan 20080 ppb
Jan 20050 ppb

90th-percentile lead per sampling round (90% of the homes sampled were at or below this level). Black line: EPA’s 15 ppb action level; under the Lead and Copper Rule Improvements the action level becomes 10 ppb from 2027.

PFAS

This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5).

ZIP codes served

ZIP codes whose center lies in this system’s service area.

What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.

Questions

Has Dorchester had drinking water violations?

Health-based violations since 2016: Long Term 2 Enhanced Surface Water Treatment Rule. All are listed as resolved.

What is the lead level in Dorchester water?

The latest 90th-percentile lead result (Jan 2025) was 0 ppb. EPA’s action level is 15 ppb (10 ppb from 2027).

Does Dorchester have PFAS in its water?

This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5 covers systems serving over 3,300 people and a sample of smaller ones).