We found 58 public water systems that could serve the same population as Tri-county Cooperative Oil Company (ordered by population size).
| Name | Areas served | Population served | Contaminant count | Violation count |
|---|---|---|---|---|
| Saint James | St. James | 4,611 | 0 | 1 |
| Madelia | Madelia | 2,319 | 0 | 4 |
| Butterfield | Butterfield | 586 | 0 | 2 |
| Watonwan Rest Area Mndot | County of Watonwan | 500 | 0 | 1 |
| St. John's Evangelical Church | County of Watonwan | 300 | 0 | 3 |
| Lewisville | Lewisville | 247 | 0 | 0 |
| Butterfield Foods Company | County of Watonwan | 160 | 0 | 0 |
| Long Lake Lutheran Church | County of Watonwan | 150 | 0 | 0 |
| St. John's Lutheran Church | County of Watonwan | 150 | 0 | 1 |
| East Sveadahl Lutheran Church | County of Watonwan | 130 | 0 | 0 |
| Kansas Lake Lutheran Church | County of Watonwan | 130 | 0 | 0 |
| Ormsby | Ormsby | 129 | 0 | 7 |
| Odin | Odin | 106 | 0 | 0 |
| South Fork Golf Club | County of Watonwan | 100 | 0 | 0 |
| Darfur | Darfur | 87 | 0 | 0 |
| Lasalle | Lasalle | 85 | 0 | 0 |
| West Sveadahl Lutheran Church | County of Watonwan | 75 | 0 | 0 |
| First Mennonite Church | County of Watonwan | 45 | 0 | 0 |
| St John's Lutheran School | County of Watonwan | 33 | 0 | 0 |
| Dels Tavern | County of Watonwan | 25 | 0 | 0 |
| Gopher Concrete Products | County of Watonwan | 25 | 0 | 0 |
| Lasalle Farmers Grain Elevator | County of Watonwan | 25 | 0 | 0 |
| Godahl Rec Hall | County of Watonwan | 25 | 0 | 0 |
| Godahl Store | County of Watonwan | 25 | 0 | 0 |
| Shilo Ranch Kennels | County of Watonwan | 25 | 0 | 0 |
| Voss Park Campground | County of Watonwan | 25 | 0 | 0 |
| Watonwan Co Country Club | County of Watonwan | 25 | 0 | 0 |
| Malmgren Implement | County of Watonwan | 25 | 0 | 0 |
| St James Mun Airport | County of Watonwan | 25 | 0 | 0 |
| South Central Electric Association | County of Watonwan | 25 | 0 | 0 |
| Tri-county Implement Company | County of Watonwan | 25 | 0 | 0 |
| St James Truck Station-mndot | County of Watonwan | 25 | 0 | 0 |
| Watowan Farm Service | County of Watonwan | 25 | 0 | 0 |
| Northern States Power Co | County of Watonwan | 25 | 0 | 0 |
| St James Greenhouse | County of Watonwan | 25 | 0 | 0 |
| Hormel And Company | County of Watonwan | 25 | 0 | 0 |
| Tenney Feeder Pig Market | County of Watonwan | 25 | 0 | 0 |
| Kimball Korner | County of Watonwan | 25 | 0 | 0 |
| Watonwan County Eagles Nest Park | County of Watonwan | 25 | 0 | 0 |
| Sands Country Cove Campground | County of Watonwan | 25 | 0 | 0 |
| Lasalle Elem School | County of Watonwan | 25 | 0 | 0 |
| Lasalle Food Processing | County of Watonwan | 25 | 0 | 0 |
| Lasalle Farmers Grain Co | County of Watonwan | 25 | 0 | 0 |
| Terry | County of Watonwan | 25 | 0 | 0 |
| State Bank Of Lasalle | County of Watonwan | 25 | 0 | 0 |
| Tony Downs Foods Company | County of Watonwan | 25 | 0 | 0 |
| Conrads Community Store | County of Watonwan | 25 | 0 | 0 |
| Dutchs On And Off Sale | County of Watonwan | 25 | 0 | 0 |
| Dels Foods | County of Watonwan | 25 | 0 | 0 |
| Fieldon Church | County of Watonwan | 25 | 0 | 0 |
| St Olaf | County of Watonwan | 25 | 0 | 0 |
| St Olaf Church | County of Watonwan | 25 | 0 | 0 |
| Bird Cage Motel | County of Watonwan | 25 | 0 | 0 |
| Madelia Mobile Village | County of Watonwan | 25 | 0 | 0 |
| St James Place, Mobile Home C | County of Watonwan | 25 | 0 | 0 |
| Watona Park | County of Watonwan | 25 | 0 | 0 |
| Main Street Cusine Catering | County of Watonwan | 25 | 0 | 0 |
| Country Village Mob Hm Pk | County of Watonwan | 25 | 0 | 0 |