Idaho Dams
395 dams tracked by the National Inventory of Dams
Total Dams
395
High Hazard
97
24.6%
Poor / Unsatisfactory
42
Average Age
76 yrs
Hazard Classification
High97 (24.6%)
Significant141 (35.7%)
Low156 (39.5%)
Condition Assessment
Satisfactory76 (19.2%)
Fair248 (62.8%)
Poor / Unsatisfactory42 (10.6%)
Not Rated29 (7.3%)
Federal
33
State
14
Local
18
Private
325
Tallest Dams
- Thompson Mtis789 ft
- Dworshak Dam717 ft
- Anderson Ranch Dam456 ft
- Arrowrock Dam350 ft
- Lucky Peak Dam340 ft
High Hazard Dams
- Thompson MtisHigh
- Dworshak DamHigh
- Anderson Ranch DamHigh
- Arrowrock DamHigh
- Lucky Peak DamHigh
Poor Condition Dams
- Magic DamUnsatisfactory
- Fish CreekPoor
- OrchardPoor
- Saint JohnUnsatisfactory
- Louisa CreekPoor
All Dams in Idaho
Showing 251–275 of 395
| Dam Name | Height (ft) | Year | Hazard | Condition |
|---|---|---|---|---|
| Haul Road Pond (Monsanto) Caribou County | 30 | 2009 | Low | Satisfactory |
| Hardisty Wilson West Owyhee County | 18 | 1918 | Low | Fair |
| Hardisty Wilson East Owyhee County | 9 | 1918 | Low | Satisfactory |
| Hardisty Owyhee County | 31 | 1914 | Significant | Fair |
| Hansen Latah County | 18 | 1976 | Significant | Satisfactory |
| Hancock Adams County | 29 | 1931 | Significant | Fair |
| Hammond Bear Lake County | 33 | 1933 | Significant | Fair |
| Hall Elmore County | 33 | 1945 | Significant | Poor |
| Hagberry Owyhee County | 23 | 1925 | Low | Fair |
| Grouse Creek North Custer County | 110 | 1994 | Significant | Satisfactory |
| Grouse Creek Main Dam Bonner County | 17 | 1992 | Low | Fair |
| Grasmere South Dike Owyhee County | 11 | 1909 | Low | Fair |
| Grasmere North Dam Owyhee County | 22 | 1936 | Significant | Poor |
| Grasmere Middle Dam Owyhee County | 16 | 1936 | Low | Poor |
| Grasmere East Dam Owyhee County | 11 | — | Significant | Poor |
| Granite Lake Valley County | 25 | 1949 | Significant | Fair |
| Grace Main Caribou County | 52 | 1908 | High | Fair |
| Gorley Creek Dike Lemhi County | 16 | 1913 | Low | Poor |
| Gorley Creek Lemhi County | 19 | 1913 | Low | Poor |
| Goose Lake Adams County | 27 | 1919 | High | Fair |
| Glendale Franklin County | 73 | 1930 | High | Fair |
| Gimlet Blaine County | 24 | 1987 | Significant | Fair |
| Gem State Right Dike Bonneville County | 30 | 1988 | High | Satisfactory |
| Gem State Left Dike Bonneville County | 30 | 1988 | High | Satisfactory |
| Gem State Bonneville County | 40 | 1988 | High | Satisfactory |
Data sourced from the National Inventory of Dams (NID). Hazard classification reflects potential consequences of failure, not the likelihood of failure.