CITY WATER-SYSTEM LEDGER
Oak Brook, Illinois
EPA’s September 2026 export lists 2 active community water systems serving Oak Brook, Illinois, with 0 current-violation flags and 0 serious-violator flags among the covered systems.
Source: EPA SDWIS system-search export · Active community systems serving 2,500+ people · Snapshot 13 Sep 2026
01 / SYSTEMS
Water systems serving Oak Brook, Illinois
EPA associates 2 covered systems with Oak Brook, Illinois; their reported population-served values total 14,761 and may overlap.
Ordered by reported population served. Open any record for separate health, monitoring, notice, other, and serious-violator flags.
| Water system | Population served | Primary source | Current export status |
|---|---|---|---|
| Oak BrookIL0430700 | 9,400 | Surface water purchased | No current violation flagged |
| Aqua Illinois-Oak BrookIL0430055 | 5,361 | Surface water purchased | No current violation flagged |
02 / SOURCE MIX
Primary water sources for Oak Brook, Illinois
EPA classifies 2 systems serving Oak Brook, Illinois across 1 primary-source categories; Surface water purchased is the largest category with 2 systems.
It is the sum of each listed system's reported population served, not a census estimate. Service areas can overlap and some systems list multiple cities or counties.