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 1401–1425 of 2,990
| Dam Name | Height (ft) | Year | Hazard | Condition |
|---|---|---|---|---|
| Jackson Lake Meagher County | 32 | 1936 | High | Unsatisfactory |
| Jackson (Madison) Madison County | 34 | 1959 | High | Poor |
| Jakes Dam Fergus County | 19 | 1946 | Low | Not Rated |
| Jamgo #1 Musselshell County | 16 | 1955 | Low | Not Rated |
| Ja Montgomery #1 Rosebud County | 20 | 1946 | Low | Not Rated |
| Janitell #1 Prairie County | 18 | 1949 | Low | Not Rated |
| January Detention Dam Valley County | 31 | 1960 | Low | Unsatisfactory |
| Jappe Chouteau County | 36 | 1956 | Low | Not Rated |
| Jardee Carter County | 20 | 1966 | Low | Not Rated |
| Jarden Reservoir Garfield County | 37 | 1947 | Low | Not Rated |
| Jasper Blaine County | 21 | 1938 | Low | Not Rated |
| Jawbone Dam #1 Wheatland County | 35 | 1966 | High | Satisfactory |
| Jawbone Dam #2 Wheatland County | 36 | 1966 | High | Satisfactory |
| Jawbone Dike #1 Wheatland County | 13 | 1966 | High | Satisfactory |
| J B and R Haversland Daniels County | 20 | 1959 | Low | Not Rated |
| J B Long and Company #2 Lewis and Clark County | 20 | 1930 | Low | Not Rated |
| J B Long and Company #3 Lewis and Clark County | 34 | 1950 | Low | Not Rated |
| J Deckert #1 Dawson County | 20 | 1960 | Low | Not Rated |
| Jeffers #1 Big Horn County | 26 | 1959 | Low | Not Rated |
| Jeffrey #1 Garfield County | 18 | 1958 | Low | Not Rated |
| Jeffrey #2 Garfield County | 25 | 1922 | Significant | Not Rated |
| Jello Carter County | 20 | 1886 | Low | Not Rated |
| Jelly Bean Fergus County | 16 | 1940 | Low | Not Rated |
| Jennaway #1 Musselshell County | 16 | 1960 | Low | Not Rated |
| Jensen Dam Garfield County | 30 | 1950 | Low | Not Rated |
Data sourced from the National Inventory of Dams (NID). Hazard classification reflects potential consequences of failure, not the likelihood of failure.