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 2326–2350 of 2,606
| Dam Name | Height (ft) | Year | Hazard | Condition |
|---|---|---|---|---|
| Thompson, Frank Lewis and Clark County | 20 | 1972 | Low | Not Rated |
| Thora #2 McCone County | 17 | 1946 | Low | Not Rated |
| Thorn McCone County | 10 | 1971 | Low | Not Rated |
| Three Dollar Bill Toole County | 24 | 1970 | Low | Not Rated |
| Three Forks Rosebud County | 17 | 1953 | Low | Not Rated |
| Threemile Storage Blaine County | 12 | 1937 | Low | Not Rated |
| Three Pronged Fork Dam Chouteau County | 10 | 1965 | Low | Not Rated |
| Three Trees Detention Dam Valley County | 16 | 1954 | Low | Unsatisfactory |
| Thretening Times Blaine County | 20 | 1950 | Low | Not Rated |
| Tigar Milk Valley County | 15 | 1965 | Low | Not Rated |
| Tiger #1 Blaine County | 15 | 1930 | Low | Not Rated |
| Tiger #2 Blaine County | 15 | 1960 | Low | Not Rated |
| Tillman #1 (Dawson) Dawson County | 15 | 1934 | Low | Not Rated |
| Tillman #3 McCone County | 18 | 1970 | Low | Not Rated |
| Timber Dawson County | 20 | 1945 | Low | Not Rated |
| T L Johnson #1 Rosebud County | 22 | 1957 | Low | Not Rated |
| T L Johnson #5 Rosebud County | 15 | 1948 | Low | Not Rated |
| Todd #1 Custer County | 19 | 1936 | Low | Not Rated |
| Tolksdorf #1 Richland County | 20 | 1953 | Low | Not Rated |
| Tolksdorf #2 Richland County | 15 | 1957 | Low | Not Rated |
| Tom #1 Garfield County | 20 | 1950 | Low | Not Rated |
| Tom #2 Garfield County | 20 | 1962 | Low | Not Rated |
| Tomahawk Detention Dam Valley County | 23 | 1962 | Low | Unsatisfactory |
| Tomeyer #1 Toole County | 15 | 1920 | Low | Not Rated |
| Tomeyer #2 Toole County | 15 | 1956 | Low | Not Rated |
Data sourced from the National Inventory of Dams (NID). Hazard classification reflects potential consequences of failure, not the likelihood of failure.