| Arlington Heights Extended Water Service Area |
| CPH Orchards of Anne Subdivision |
| CPH SSA-6 |
| CPH-Camp McDonald Corridor |
| CPH-Country Club Villas at Rob Roy |
| CPH-Emeritus of Prospect Heights |
| CPH-Fairway Estates Subdivision |
| CPH-Rob Roy Country Club Village |
| Chicago Executive Airport |
| Cook County Forest Preserve District |
| Illinois American Water Co. |
| Mount Prospect Extended Water Service Area |
| Private Wells |
| Village of Glenview (North Maine) |