Water quality in O'Fallon, Illinois
O'Fallon is in St. Clair County. 54 active public water systems serve the county; 23 had an EPA violation in the past three years.
Most likely your provider
Your location is within the outer bounds of this system's EPA service area.
Other community water systems in St. Clair County
27 systems, nearest first| System | Serves | Status | Rules violated, 3 yr | Distance |
|---|---|---|---|---|
| Valley View Estates O Fallon |
580 | 2 | 1.6 mi | |
| Lake Suzanne MHP Shiloh |
108 | 0 | 2.1 mi | |
| American Water Oper and Maintenance, LLC |
6,779 | 0 | 3.7 mi | |
| Meadowbrook MH Community, LLC Belleville |
463 | 4 | 4.1 mi | |
| IL American-East ST Louis East St Louis |
131,368 | 0 | 5.3 mi | |
| Lebanon Lebanon |
4,714 | 2 | 5.6 mi | |
| Caseyville Caseyville |
13,798 | 1 | 7.3 mi | |
| Arapaho Village MHP Belleville |
368 | 0 | 7.6 mi | |
| Mascoutah Mascoutah |
8,759 | 1 | 8.1 mi | |
| Summerfield Summerfield |
347 | 0 | 8.7 mi | |
| Mound Pwd |
1,243 | 4 | 8.8 mi | |
| Freeburg Freeburg |
4,707 | 0 | 11.0 mi | |
| Southwestern IL Correctional Center East St Louis |
563 | 0 | 12.0 mi | |
| Fsh Water Commission Smithton |
313 | 2 | 12.3 mi | |
| Millstadt Millstadt |
4,071 | 0 | 12.9 mi | |
| Cahokia Heights Cahokia |
12,528 | 0 | 13.1 mi | |
| S L M Water Commission |
385 | 1 | 13.4 mi | |
| Smithton Smithton |
4,381 | 1 | 14.0 mi | |
| Fayetteville Fayetteville |
490 | 0 | 15.5 mi | |
| Prairie Dupont Pwd |
1,863 | 0 | 15.6 mi | |
| Dupo Dupo |
4,684 | 1 | 16.2 mi | |
| Ildu Lepere Mhp, LLC Dupo |
250 | 3 | 17.1 mi | |
| Kaskaskia Water District New Athens |
0 | 1 | 18.3 mi | |
| New Athens New Athens |
1,970 | 1 | 18.4 mi | |
| ST Libory St Libory |
628 | 1 | 18.7 mi |
Non-community systems in St. Clair County (26: schools, campgrounds, workplaces, restaurants)
These systems serve places you visit rather than homes.
| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Walmart Supercenter 201 |
30 | 0 | 0 | |
|
Schnucks 205 Belleville |
25 | 0 | 0 | |
|
Quail Restoration Association |
25 | 0 | 0 | |
|
Millstadt Sportsmans Club |
25 | 1 | 0 | |
|
New Baden Market Center |
25 | 0 | 0 | |
|
Children of Promise |
50 | 5 | 2 | |
|
ST Clair County Foley Park |
200 | 0 | 0 | |
|
Karbans Knotty Pines |
200 | 1 | 0 | |
|
ST Michaels Church |
50 | 1 | 0 | |
|
Walmart Supercenter 1418 |
25 | 0 | 0 | |
|
Twice the Ice Freeburg |
50 | 0 | 0 | |
|
New Athens Hanft PK Larry Webe |
30 | 0 | 0 | |
|
Schnucks (138297) |
30 | 0 | 0 | |
|
Schnucks (138313) |
30 | 0 | 0 | |
|
Schnucks (138321) |
30 | 0 | 0 | |
|
Twice the Ice Smithton |
30 | 0 | 0 | |
|
BK Ice Cahokia |
25 | 0 | 0 | |
|
Dierbergs |
25 | 0 | 0 | |
|
Freeburg Ice Man |
25 | 0 | 0 | |
|
Fresh Thyme Farmers Market Fairview Hgts |
25 | 0 | 0 | |
|
Scarlett's Cabaret |
25 | 3 | 1 | |
|
Schnucks #148 |
25 | 0 | 0 | |
|
Schnucks 177 O Fallon |
25 | 0 | 0 | |
|
Twice the Ice Lebanon |
25 | 0 | 0 | |
|
Twice the Ice Mascoutah |
25 | 0 | 0 | |
|
Twice the Ice ST Libory |
25 | 2 | 0 |
About this data
Water systems are matched to St. Clair County, nearest to O'Fallon first. Your exact provider depends on your address and connection; the largest community water system in a county is usually the city or town utility. Distances are measured to the centre of the service area EPA publishes for the system or, for systems without one, to the centre of the first town EPA lists the system as serving, from Census Bureau place files.
Town locations and ZIP code areas come from U.S. Census Bureau 2020 files.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Illinois records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.