State Hub
Illinois Water Quality
1,134
Utilities in database
12.0M
Residents served
20%
On private wells
3
Key contaminants tracked
Drinking Water in Illinois
Illinois has 1,134 community water systems serving approximately 12.0 million residents. Primary water sources include groundwater. The most commonly reported contaminants include lead, disinfection byproducts, nitrates. 20% of Illinois residents rely on private wells. IEPA holds primary enforcement authority under the Safe Drinking Water Act.
Utilities in Illinois
951–975 of 1,134Farmersville
IL1350200 · 784 served
Hurst
IL1990450 · 782 served
Orangeville
IL1770350 · 780 served
Greenview
IL1290100 · 778 served
Prairie Path Water Company-camelot
IL1975200 · 777 served
Prairie Path Water Company-walk Up Woods
IL1115800 · 775 served
North City
IL0550300 · 772 served
Woodhull
IL0730750 · 771 served
North Regional Water Fac
IL0435850 · 770 served
Elverado Water District
IL0770010 · 763 served
Fyre Lake Water Company
IL1315050 · 760 served
Prairie Du Rocher
IL1570400 · 759 served
Alhambra
IL1190050 · 755 served
Sugar Crk Pwd
IL1675300 · 754 served
Ej Water-watson
IL0490500 · 754 served
Menard Rural Water Coop
IL1290010 · 753 served
Dongola
IL1810200 · 752 served
Ogden
IL0190500 · 750 served
Lamoille
IL0110500 · 750 served
Camargo
IL0410100 · 750 served
Findlay
IL1730100 · 750 served
Sunny Acres Mhp
IL0915545 · 750 served
Hennepin Pwd
IL1555100 · 750 served
Bluffs
IL1710100 · 748 served
Stewardson
IL1730400 · 747 served
Key Contaminant Concerns in Illinois
Lead
Lead is a naturally occurring heavy metal that was widely used in plumbing infrastructure until it was banned for new installations in 1986. An estimated 9.2 million lead service lines still connect homes to public water mains across the United States, along with millions of homes with lead solder in their internal plumbing.
Nitrates
Nitrate (NO₃⁻) is a nitrogen-containing compound that forms naturally through the decomposition of organic matter. At elevated concentrations — almost always from human activity — nitrate interferes with the blood's ability to carry oxygen. The United States produces over 23 million tons of nitrogen fertilizer annually, making agricultural runoff the dominant source of nitrate contamination.
DBPs
When utilities add chlorine to water to kill pathogens, it reacts with dissolved organic matter — leaves, algae, soil — to produce disinfection byproducts (DBPs). Over 600 DBPs have been identified. The EPA regulates two groups: total trihalomethanes (TTHMs, including chloroform) and haloacetic acids (HAA5). DBP levels tend to be highest in surface water systems and in warm months when organic matter is elevated.
Illinois Water FAQs
Quick Links
Data source: Utility data from EPA SDWIS. 1,134 active community water systems ingested. CCR contaminant data ingestion in progress.
Last updated: 2026-04-17