Montana Dams
2,990 dams tracked by the National Inventory of Dams
Total Dams
2,990
High Hazard
188
6.3%
Poor / Unsatisfactory
132
Average Age
74 yrs
Hazard Classification
High188 (6.3%)
Significant193 (6.5%)
Low2,606 (87.2%)
Condition Assessment
Satisfactory113 (3.8%)
Fair44 (1.5%)
Poor / Unsatisfactory132 (4.4%)
Not Rated2,701 (90.3%)
Federal
278
State
151
Local
84
Private
2,466
Tallest Dams
- Yankee Doodle Tailings Dam570 ft
- Hungry Horse Dam564 ft
- Libby Dam422 ft
- Noxon Rapids260 ft
- Fort Peck Dam256 ft
High Hazard Dams
- Yankee Doodle Tailings DamHigh
- Hungry Horse DamHigh
- Libby DamHigh
- Noxon RapidsHigh
- Fort Peck DamHigh
Poor Condition Dams
All Dams in Montana
Showing 1926–1950 of 2,990
| Dam Name | Height (ft) | Year | Hazard | Condition |
|---|---|---|---|---|
| G Newman #1 Rosebud County | 25 | 1961 | Low | Not Rated |
| Gmg Cascade County | 20 | 1960 | Low | Not Rated |
| Gliblet Garfield County | 21 | 1974 | Low | Not Rated |
| Glen Lake Lincoln County | 14 | 1950 | High | Poor |
| Glendive Sewage Disposal Ponds Dawson County | 8 | 1959 | Low | Not Rated |
| Gleason Lake Ravalli County | 14 | 1922 | Low | Not Rated |
| Glasscock Reservoir #2 Garfield County | 20 | 1937 | Low | Not Rated |
| Glasscock Reservoir #1 Garfield County | 20 | 1947 | Low | Not Rated |
| Glasscock Bros #2 Rosebud County | 15 | 1960 | Low | Not Rated |
| Glasscock Bros #1 Garfield County | 15 | 1935 | Low | Not Rated |
| Glasscock #2 Custer County | 22 | 1954 | Low | Not Rated |
| Glasscock #1 Custer County | 27 | 1960 | Low | Not Rated |
| Glasgow Sewage Lagoon Valley County | 9 | 1955 | Low | Not Rated |
| Gladowski Richland County | 25 | 1950 | Low | Not Rated |
| Gladiolus Toole County | 30 | 1945 | Low | Not Rated |
| Glacier Lake South Dam Carbon County | 20 | 1937 | High | Satisfactory |
| Glacier Lake North Dam Carbon County | 57 | 1937 | High | Satisfactory |
| Glacier Lake Dam Missoula County | 12 | 1915 | Significant | Not Rated |
| Gjp Suta Toole County | 15 | 1960 | Low | Not Rated |
| Gipsy Lake Dam Meagher County | 9 | 1872 | Low | Not Rated |
| Gildford Colony #1000 Hill County | 20 | 1960 | Low | Not Rated |
| Gilda Radner Phillips County | 20 | 1962 | Low | Not Rated |
| Gibson Dam Teton County | 199 | 1929 | High | Not Available |
| Gibbs, Gerold Garfield County | 21 | 1969 | Low | Not Rated |
| Gibbs #1 McCone County | 12 | 1945 | Low | Not Rated |
Data sourced from the National Inventory of Dams (NID). Hazard classification reflects potential consequences of failure, not the likelihood of failure.