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 2026–2050 of 2,606
| Dam Name | Height (ft) | Year | Hazard | Condition |
|---|---|---|---|---|
| Ronning #1 Custer County | 20 | 1958 | Low | Not Rated |
| Rosann Rosanna Dana Sweet Grass County | 50 | 1939 | Low | Not Rated |
| Rosa Spring Dam #1 Garfield County | 12 | 1960 | Low | Not Rated |
| Rosecraze Carter County | 20 | 1954 | Low | Not Rated |
| Ro Smith #1 Rosebud County | 18 | 1952 | Low | Not Rated |
| Ross Dam Garfield County | 16 | 1955 | Low | Not Rated |
| Roth #1 Phillips County | 15 | 1950 | Low | Not Rated |
| Rough Creek Dam Rosebud County | 35 | 1960 | Low | Not Rated |
| Round Butte Reservoir Rosebud County | 25 | 1964 | Low | Not Rated |
| Roundup Sewage Lagoon Musselshell County | 12 | 1957 | Low | Not Rated |
| Row Phillips County | 20 | 1950 | Low | Not Rated |
| R Owen #1 Carter County | 12 | 1923 | Low | Not Rated |
| R Owen #2 Carter County | 7 | 1920 | Low | Not Rated |
| Rowley Cb&O #1 Big Horn County | 8 | 1960 | Low | Not Rated |
| Royal Champion Blaine County | 15 | 1963 | Low | Not Rated |
| R Pankratz #1 Phillips County | 12 | 1935 | Low | Not Rated |
| Rp Griffith #1 Musselshell County | 19 | 1963 | Low | Not Rated |
| R Schmitz #1 Richland County | 20 | 1970 | Low | Not Rated |
| Rudy'S Dam Carter County | 11 | 1932 | Low | Unsatisfactory |
| Ruff Creek Retention Dam McCone County | 26 | 2003 | Low | Not Rated |
| Ruins Detention Dam Valley County | 35 | 1965 | Low | Poor |
| Ruseteun #2 Fergus County | 25 | 1962 | Low | Not Rated |
| Rusley #2 Fallon County | 18 | 1955 | Low | Not Rated |
| Russell #1 Powder River County | 15 | 1941 | Low | Not Rated |
| Russian Frank Reservoir Garfield County | 18 | 1955 | Low | Not Rated |
Data sourced from the National Inventory of Dams (NID). Hazard classification reflects potential consequences of failure, not the likelihood of failure.