We found 30 public water systems in Warren county (ordered by population size).
| Name | Areas served | Population served | Contaminant count | Violation count |
|---|---|---|---|---|
| Warren Water District | Indianola | 18,045 | 47 | 5 |
| Indianola Water Supply | Indianola | 14,782 | 19 | 8 |
| Norwalk Water Supply | Norwalk | 8,948 | 0 | 8 |
| Carlisle Water Supply | Carlisle | 3,876 | 0 | 7 |
| Lakewood Benefited Water District | Norwalk | 1,972 | 0 | 0 |
| Milo Public Water Supply | Milo | 775 | 0 | 21 |
| Hartford Water Works | Hartford | 759 | 0 | 0 |
| Lake Ahquabi State Park | County of Warren | 500 | 0 | 0 |
| New Virginia Water Supply | New Virginia | 489 | 0 | 10 |
| Martensdale Water Supply | Martensdale | 465 | 0 | 2 |
| Lacona Water Supply | Lacona | 386 | 0 | 5 |
| Southeast Warren Community School | County of Warren | 370 | 0 | 0 |
| Cumming Water Treatment Plant | Cumming | 351 | 0 | 6 |
| Camp Wesley Woods | County of Warren | 258 | 0 | 0 |
| North American Mobile Home Park | Indianola | 235 | 0 | 1 |
| Hartford Mobile Home Park Llc | Hartford | 183 | 0 | 0 |
| Saint Marys Water Corporation | Saint Marys | 131 | 0 | 24 |
| Bart's Full Service Station | New Virginia | 106 | 0 | 0 |
| Teaser's Palace | Carlisle | 104 | 0 | 0 |
| Parkside Mobile Home Park | Indianola | 90 | 0 | 0 |
| Wilshire Hills C/ogoodhue Ins. | County of Warren | 85 | 0 | 0 |
| Ackworth | Ackworth | 83 | 0 | 0 |
| Cozy Cafe | County of Warren | 70 | 0 | 0 |
| Echo Valley Housing Developmen | County of Warren | 65 | 0 | 0 |
| Wilshire Hills | County of Warren | 50 | 0 | 0 |
| WOW SERVICES INC | New Virginia | 27 | 0 | 0 |
| Frank's County Store | County of Warren | 25 | 0 | 0 |
| Shady Oak Golf Course | County of Warren | 25 | 0 | 0 |
| Otter Crk Pk-warren Conservati | Indianola | 25 | 0 | 0 |
| Stuckey's Pecan Shoppe #322 | County of Warren | 25 | 0 | 0 |