Montana public water systems
2,382 active systems regulated under the Safe Drinking Water Act, serving a reported 1.2M people across 75 counties.
Dataset updated . Source: EPA SDWIS/ECHO, refreshed quarterly.
Active systems
2,382
Population served
1.2M
Community systems
847
Groundwater share
88.6%
System types in Montana
847
Community water system
316
Non-transient non-community water system
1,219
Transient non-community water system
Largest water systems in Montana
| # | Water system | County | Population served | Type | Source |
|---|---|---|---|---|---|
| 1 | Billings City of | Yellowstone | 114,000 | Community | Surface water |
| 2 | Missoula Water | Missoula | 68,200 | Community | Groundwater |
| 3 | Great Falls City of | Cascade | 60,000 | Community | Surface water |
| 4 | Bozeman City of | Gallatin | 56,000 | Community | Surface water |
| 5 | Butte Silverbow Water Dept | Silver Bow | 33,000 | Community | Surface water |
| 6 | Helena Water System | Lewis and Clark | 32,091 | Community | Surface water |
| 7 | Kalispell Public Works | Flathead | 25,000 | Community | Groundwater |
| 8 | Montana State University Bozeman | Gallatin | 19,200 | Non-transient non-community | Purchased surface water |
| 9 | University of Montana | Missoula | 15,000 | Non-transient non-community | Purchased groundwater |
| 10 | Billings Heights Co Water Dist of | Yellowstone | 12,000 | Community | Purchased surface water |
| 11 | Belgrade City of | Gallatin | 10,460 | Community | Groundwater |
| 12 | Whitefish City of | Flathead | 10,418 | Community | Surface water |
| 13 | Havre City of | Hill | 9,921 | Community | Surface water |
| 14 | West Yellowstone Town of | Gallatin | 9,899 | Community | Groundwater |
| 15 | Miles City City of | Custer | 9,565 | Community | Surface water |
| 16 | Malmstrom Air Force Base | Cascade | 8,850 | Community | Purchased surface water |
| 17 | Flathead County Water and Sewer | Flathead | 7,775 | Community | Groundwater |
| 18 | Livingston City of | Park | 7,500 | Community | Groundwater |
| 19 | Anaconda Water Department | Deer Lodge | 6,750 | Community | Groundwater |
| 20 | Laurel Municipal Water System | Yellowstone | 6,339 | Community | Surface water |
| 21 | Bigfork County Water and Sewer | Flathead | 6,100 | Community | Groundwater |
| 22 | Lewistown City of | Fergus | 5,923 | Community | Groundwater |
| 23 | Lockwood Water and Sewer District | Yellowstone | 5,900 | Community | Surface water |
| 24 | Rocky Mountain College | Yellowstone | 5,700 | Non-transient non-community | Purchased surface water |
| 25 | Hamilton City of | Ravalli | 5,585 | Community | Groundwater |
By county
Flathead326 systemsMissoula244 systemsGallatin207 systemsLewis and Clark163 systemsRavalli129 systemsYellowstone118 systemsCascade99 systemsLincoln92 systemsLake90 systemsPark58 systemsBeaverhead48 systemsMadison45 systemsSanders44 systemsJefferson42 systemsMineral37 systemsCarbon36 systemsDawson32 systemsStillwater31 systemsGlacier27 systemsSilver Bow24 systemsBig Horn23 systemsGranite22 systemsBroadwater20 systemsFergus20 systemsToole18 systemsPowell17 systemsDeer Lodge16 systemsHill16 systemsTeton15 systemsRosebud15 systemsSweet Grass15 systemsRichland15 systemsBingham13 systemsValley13 systemsPondera12 systemsChouteau12 systemsBlaine12 systemsPhillips12 systemsCuster11 systemsMusselshell8 systemsSheridan8 systemsWheatland8 systemsLiberty8 systemsMeagher8 systemsJudith Basin8 systemsPrairie7 systemsMcCone6 systemsGarfield6 systemsCarter5 systemsRoosevelt4 systemsFallon4 systemsGolden Valley4 systemsMcKenzie3 systemsPowder River3 systemsBannock3 systemsTreasure3 systems
Bonneville2 systems
Wibaux2 systems
Daniels2 systems
Allegan1 systems
Okanogan1 systems
Elmore1 systems
Glenn1 systems
Steele1 systems
Lafayette1 systems
Sevier1 systems
Grand1 systems
San Juan1 systems
Washington1 systems
Idaho1 systems
Hays1 systems
Petroleum1 systems
Montgomery1 systems
Mercer1 systems
Newton1 systems