Public Water Systems
2,263 active public water systems in MT, tracked from EPA's Safe Drinking Water Information System (SDWIS) across all 50 states. See our methodology.
| System Name | Location | Population | Violations | PFAS |
| St Regis Camp Motel and Frosty | St. Regis, MT | 94 | 22 | - |
| Lavina School District | Lavina, MT | 94 | 322 | - |
| Buckhorn Bar Augusta | Augusta, MT | 94 | 41 | - |
| Lahood Park Cardwell | Cardwell, MT | 94 | 115 | - |
| Piegan Border Station | Helena, MT | 94 | 1,081 | - |
| Piney Campground | Philipsburg, MT | 94 | 48 | - |
| Potomac Bar | Bonner, MT | 93 | 393 | - |
| Livingston Campground | Livingston, MT | 93 | 143 | - |
| Crossroads Christian Fellowship | Missoula, MT | 93 | 27 | - |
| Lakeview Park Estates Homeowners Assoc | Lakeside, MT | 92 | 18 | - |
| Bearmouth RV Park | Missoula, MT | 92 | 96 | - |
| Rockport Colony | Pendroy, MT | 92 | 203 | - |
| Rustic Hut | Florence, MT | 92 | 50 | - |
| Blue Mountains RV Park | Eureka, MT | 92 | 27 | - |
| Indiana Univ Geologic Station | Bloomington, MT | 92 | 62 | - |
| Mountain View RV Park | Kalispell, MT | 92 | 14 | - |
| Midway Colony Inc | Conrad, MT | 92 | 28 | - |
| HI-Line Colony | Chester, MT | 92 | 78 | - |
| Tactic Training Center | Bozeman, MT | 92 | 0 | - |
| St John the Baptist Church | Frenchtown, MT | 91 | 29 | - |
| Pleasant Hill Estates HOA | Kalispell, MT | 90 | 263 | - |
| Galen Facility | Butte, MT | 90 | 233 | - |
| Masonic Home of Montana | East Helena, MT | 90 | 95 | - |
| West Glacier Wua | West Glacier, MT | 90 | 64 | - |
| Buena Vista Community, Inc | Missoula, MT | 90 | 91 | - |
| I 94 Mobile Home Park | Renton, MT | 90 | 119 | - |
| Rivershore Community LLC | Port Orchard, MT | 90 | 1,698 | - |
| Westana Mobile Manor Hamilton | Billings, MT | 90 | 130 | - |
| Springhill Park Subdivision | Bozeman, MT | 90 | 1,959 | - |
| West Fork Cabin Camp | Helena, MT | 90 | 49 | - |
| Lewis and Clark Campground | Dillon, MT | 90 | 80 | - |
| North Havre County Water Dist | Havre, MT | 90 | 886 | - |
| Greenfield Elem School Dist 75 | Fairfield, MT | 90 | 38 | - |
| Ranch Co Water & Sewer Dist The | Bigfork, MT | 90 | 153 | - |
| Clearview Heights Water Assn | Polson, MT | 90 | 200 | - |
| Birch Creek Outdoor Ed Center | Dillon, MT | 90 | 46 | - |
| Montana Coffee Trader Inc | Whitefish, MT | 90 | 120 | - |
| Kenworth Sales Co | Spokane, MT | 90 | 27 | - |
| Furniture Row Billings | Denver, MT | 90 | 119 | - |
| Ncmrwa North Havre Cwd Leg | Helena, MT | 90 | 17 | - |
| Forest River Mobile Home and RV Park | Kalispell, MT | 90 | 17 | - |
| Solid Rock Ventures LLC | Kalispell, MT | 90 | 9 | - |
| Indian Springs RV | Eureka, MT | 90 | 13 | - |
| Big Sky Grocery Unapproved | Moore, MT | 90 | 6 | - |
| Buffalo Mountain Subdivision | Bigfork, MT | 90 | 4 | - |
| Nine Mile Co Water/Sewer District | Sunburst, MT | 90 | 13 | - |
| Elkhorn Health and Rehabilitation LLC | Clancy, MT | 89 | 257 | - |
| Paradise Cove | Kalispell, MT | 89 | 78 | - |
| Hillcrest Colony | Power, MT | 89 | 13 | - |
| Marysville House | Marysville, MT | 88 | 119 | - |