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 |
| Ravalli Electric Co Op | Missoula, MT | 75 | 78 | - |
| Midway Townhomes Wua | Billings, MT | 75 | 10 | - |
| Sunset Colony Unapproved | Roundup, MT | 75 | 0 | - |
| Big Arm Flathead Lake Mt St Pk | Kalispell, MT | 75 | 61 | - |
| Madison River Recreation Area | Ennis, MT | 75 | 26 | - |
| Beartooth Mountain Youth Camp | Billings, MT | 75 | 62 | - |
| Theiltges Saint Thomas Camp | Monarch, MT | 74 | 24 | - |
| Mvp Holding LLC | Missoula, MT | 74 | 50 | - |
| Atanaha Event Center | Big Fork, MT | 74 | 30 | - |
| Fedex Relay Center | Billings, MT | 74 | 81 | - |
| Bison Inn Cafe | St Ignatius, MT | 73 | 246 | - |
| Montana Trailer Court | Missoula, MT | 73 | 248 | - |
| Hartland Colony | Havre, MT | 73 | 32 | - |
| Turah Meadows | Missoula, MT | 73 | 40 | - |
| Bitterroot Valley RV Park & Campground | Corvallis, MT | 72 | 93 | - |
| Lamotte School District No 43 | Bozeman, MT | 72 | 37 | - |
| Polebridge Mercantile | Polebridge, MT | 72 | 138 | - |
| Camp Child | Helena, MT | 72 | 316 | - |
| Stutzmans Country Market | St Ignatius, MT | 72 | 51 | - |
| Western Livestock Auction LLC | Great Falls, MT | 71 | 26 | - |
| Alcan Bar and Cafe | Frenchtown, MT | 71 | 88 | - |
| Evaro Bar and Casino | Missoula, MT | 71 | 365 | - |
| Rapelje Water District | Rapelje, MT | 70 | 560 | - |
| Montana Aviation Research Co | Glasgow, MT | 70 | 24 | - |
| Big Sky Trailer CT Hamilton | Hamilton, MT | 70 | 105 | - |
| Ponderosa Mb Home Subd | Bozeman, MT | 70 | 26 | - |
| Hilltop Hitching Post Inn | Marion, MT | 70 | 301 | - |
| Point Service Corporation | Bigfork, MT | 70 | 19 | - |
| Hamilton Christian Academy | Missoula, MT | 70 | 123 | - |
| Pioneer School Dist 41 | Billings, MT | 70 | 180 | - |
| Gildford Colony | Gildford, MT | 70 | 281 | - |
| Duck Creek Mobile Home Park | Billings, MT | 70 | 1,064 | - |
| Emerald Heights HOA Water & Sewer Dist | Whitefish, MT | 70 | 27 | - |
| Barnett Water Users System | Helena, MT | 70 | 332 | - |
| Sawtooth Villa | Cascade, MT | 70 | 19 | - |
| Shakopee Heights Water District | Anaconda, MT | 70 | 15 | - |
| Emmanuel Lutheran Church | Billings, MT | 70 | 381 | - |
| Lds Church Ennis | Foxboro, MT | 70 | 116 | - |
| King Ranch Subdivision | Frenchtown, MT | 70 | 55 | - |
| Wood Ridge HOA | Bigfork, MT | 70 | 23 | - |
| Sonju Industrial Inc | Bigfork, MT | 70 | 183 | - |
| Ethridge County Water District | Ethridge, MT | 70 | 13 | - |
| Storybook Hollow | Billings, MT | 70 | 134 | - |
| Clear View Academy | Heron, MT | 70 | 24 | - |
| Mission Valley United Methodist Church | Ronan, MT | 70 | 20 | - |
| Deer Lick Subdivision Water District | Haugan, MT | 70 | 47 | - |
| Meadow Brook Christian Fellowship Church | Somers, MT | 70 | 3 | - |
| Zenith Colony | Cut Bank, MT | 70 | 586 | - |
| Natural Grocers Helena | Colorado Springs, MT | 70 | 48 | - |
| Ncmrwa Shelby to Ethridge | Helena, MT | 70 | 3 | - |