We found 44 public water systems in Poweshiek county (ordered by population size).
| Name | Areas served | Population served | Contaminant count | Violation count |
|---|---|---|---|---|
| Grinnell Water Department | Grinnell | 9,278 | 0 | 4 |
| Ponderosa Utilities Inc. | Montezuma | 1,628 | 0 | 3 |
| Montezuma Muni Water Supply | Montezuma | 1,537 | 0 | 9 |
| Brooklyn Water Department | Brooklyn | 1,468 | 0 | 5 |
| Dickey's Restuarant Gas Statio | County of Poweshiek | 414 | 0 | 0 |
| Holiday Lake Water System Ltd | Brooklyn | 350 | 0 | 0 |
| Grinnell Mutual Reinsurance Co | County of Poweshiek | 350 | 0 | 0 |
| Brooklyn 80 | Brooklyn | 320 | 0 | 0 |
| Hammer Restaurant & Gas Statio | County of Poweshiek | 300 | 0 | 0 |
| Malcom Water Supply | Malcom | 287 | 0 | 3 |
| Deep River Water Supply | Deep River | 279 | 0 | 16 |
| 63-80 Truck Plaza | County of Poweshiek | 215 | 0 | 0 |
| Barnes City Water Supply | Barnes City | 176 | 0 | 4 |
| Shorty's Truck Stop | County of Poweshiek | 160 | 0 | 0 |
| Searsboro Water Supply | Searsboro | 155 | 0 | 0 |
| Oregon Trail Estates | County of Poweshiek | 125 | 0 | 0 |
| Newburg Service Association | Newburg | 114 | 0 | 0 |
| Hartwick Water System | Hartwick | 86 | 0 | 0 |
| Country Kitchen Restaurant-grinnell | County of Poweshiek | 60 | 0 | 0 |
| Guernsey Pump | County of Poweshiek | 45 | 0 | 0 |
| Ponderosa Inc-#12 & 13 | County of Poweshiek | 39 | 0 | 0 |
| Belle Plaine I80 Inc | County of Poweshiek | 35 | 0 | 0 |
| Ponderosa Inc-#18 | County of Poweshiek | 35 | 0 | 0 |
| Belle Plaine Mobile Home Park | County of Poweshiek | 30 | 0 | 0 |
| Ponderosa #8 | County of Poweshiek | 30 | 0 | 0 |
| Chesshire Chevrolet Oldsmobile | County of Poweshiek | 30 | 0 | 0 |
| East Iowa Bible Camp | County of Poweshiek | 30 | 0 | 0 |
| Ponderosa Inc-marina | County of Poweshiek | 25 | 0 | 0 |
| Manzuma Inn | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #4 | County of Poweshiek | 25 | 0 | 0 |
| M & J Foods | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #15 | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #1 | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #2 | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #10 | County of Poweshiek | 25 | 0 | 0 |
| Fun Valley Ski | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #3 | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #5 | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #7 | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa Marina | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #9 | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #16 & 17 | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #11 | County of Poweshiek | 25 | 0 | 0 |
| Ponderosa #6 | County of Poweshiek | 16 | 0 | 0 |