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Is O'Fallon, IL tap water safe?

2 utilities serve O'Fallon, by EPA’s records. Here is what EPA’s and Illinois’s records show for each, against the legal limits and the stricter health goals.

Matched to your utility using EPA records.

The short answer

Neither of the 2 utilities serving O'Fallon has a result above a legal limit or action level, or a health-based violation since 2016, in EPA’s and Illinois’s records.

O Fallon, which serves the most people here, has nothing above a health goal in EPA’s and Illinois’s records. That data covers what its report lists, not everything.

The water from O Fallon is moderately hard, 120 mg/L (7 grains per gallon). How Illinois’s water compares.

A town can be served by more than one utility, and some homes are on private wells. The name on your water bill tells you which is yours, and your ZIP code narrows it down. They are listed by how many people each serves in O'Fallon’s ZIP codes, from EPA’s estimates.

Water testing near O'Fallon

A utility tests the water it sends out. A test of your own tap shows what your pipes add, and on a private well it is the only test there is. It takes a lab Illinois certifies.

The 3 labs Illinois certifies closest to O'Fallon, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Teklab, Inc.

    Collinsville, IL · about 7 miles

    Certified for bacteria

    (618) 344-1004

  • Pace Analytical Services, LLC - Hazelwood

    Hazelwood, MO · about 28 miles

    Certified for bacteria

    (314) 432-0550

  • Precision Water Lab

    Centralia, IL · about 42 miles

    Certified for bacteria

    (618) 533-0758

Illinois Department of Public Health: Coliform bacteria and nitrate testing for private wells, with sample bottles from your local health department, or from the department's nearest regional office where there is none. You mail the sample to the lab, and results come back through the health department. Well Sampling for Coliform & Nitrate, Illinois Department of Public Health.

All 30 certified labs for Illinois

ZIP codes in O'Fallon

Which ZIP codes are in O'Fallon: Census 2020 relationship files. Which utilities serve them, and how many people: EPA SDWIS and EPA’s service area map. Each utility’s results: EPA UCMR 5, EPA SDWIS, and EPA’s and the state’s compliance monitoring, as its report lists them. How they are measured: methodology. Certified labs: Illinois Department of Public Health, certified water microbiology laboratories; distances from the Census 2020 ZIP code tabulation area gazetteer.

Near O'Fallon

Other towns in St. Clair County with a page of their own.

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