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 1376–1400 of 2,606
| Dam Name | Height (ft) | Year | Hazard | Condition |
|---|---|---|---|---|
| J-5 Ranch #2 Phillips County | 14 | 1950 | Low | Not Rated |
| J-5 Ranch #1 Phillips County | 14 | 1976 | Low | Not Rated |
| Ix Ranch Chouteau County | 46 | 1951 | Low | Not Rated |
| Ivy #3 Musselshell County | 20 | 1974 | Low | Not Rated |
| Ivy Musselshell County | 20 | 1974 | Low | Not Rated |
| Iverson Retention Dam Petroleum County | 22 | 1968 | Low | Poor |
| Iverson Toole County | 20 | 1934 | Low | Not Rated |
| I.U. Reservoir Blaine County | 44 | 1938 | Low | Not Rated |
| Itcaina Detention Dam Valley County | 20 | 1957 | Low | Satisfactory |
| Isaac Frye #4 Phillips County | 18 | 1955 | Low | Not Rated |
| Isaac Frye #3 Phillips County | 15 | 1954 | Low | Not Rated |
| Isaac Frye #1 Phillips County | 20 | 1946 | Low | Not Rated |
| Iris Garfield County | 12 | 1950 | Low | Not Rated |
| Iranian Roosevelt County | 15 | 1958 | Low | Not Rated |
| Instant Tang Carter County | 20 | 1954 | Low | Not Rated |
| Insanity Blaine County | 10 | 1955 | Low | Not Rated |
| Innes Dam Prairie County | 14 | — | Low | Not Rated |
| Indian Judy Judith Basin County | 30 | 1960 | Low | Not Rated |
| Indian #4 Fergus County | 28 | 1961 | Low | Not Rated |
| Incorporeal Chouteau County | 15 | 1935 | Low | Not Rated |
| Iehl Dawson County | 25 | 1945 | Low | Not Rated |
| Ice Skating Rink Hill County | 18 | 1940 | Low | Not Rated |
| Hyde #2 Prairie County | 18 | 1960 | Low | Not Rated |
| Hybner Hill County | 10 | 1960 | Low | Not Rated |
| Hyades Toole County | 12 | 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.