Iowa Dams
4,124 dams tracked by the National Inventory of Dams
Total Dams
4,124
High Hazard
91
2.2%
Poor / Unsatisfactory
25
Average Age
46 yrs
Hazard Classification
High91 (2.2%)
Significant274 (6.6%)
Low3,759 (91.1%)
Condition Assessment
Satisfactory259 (6.3%)
Fair81 (2.0%)
Poor / Unsatisfactory25 (0.6%)
Not Rated3,759 (91.1%)
Federal
25
State
141
Local
1,938
Private
2,014
Tallest Dams
- Coralville Dam132 ft
- Saylorville Dam125 ft
- County Basin Dam104 ft
- Rathbun Dam100 ft
- Brushy Creek Dam100 ft
High Hazard Dams
- Coralville DamHigh
- Saylorville DamHigh
- Rathbun DamHigh
- Brushy Creek DamHigh
- Big Creek Barrier DamHigh
Poor Condition Dams
All Dams in Iowa
Showing 3601–3625 of 4,124
| Dam Name | Height (ft) | Year | Hazard | Condition |
|---|---|---|---|---|
| Twelvemile Watershed Site D-60 Union County | 35 | 1999 | Low | Not Rated |
| Twenty-Sixth Street Stormwater Detention Basin Polk County | 43 | 2007 | High | Satisfactory |
| Twin Anchors Lake Dam Story County | 42 | 1960 | Low | Not Rated |
| Twin Ponies Watershed Site 17a Pottawattamie County | 54 | 1998 | Low | Satisfactory |
| Twin Ponies Watershed Site 8 Pottawattamie County | 36 | 1990 | Low | Not Rated |
| Twin Valley Lakes - East Dam Johnson County | 50 | 1965 | Significant | Poor |
| Tyer Dam Woodbury County | 22 | 1997 | Low | Not Rated |
| U-B Subwatershed Site 2-2 Monona County | 51 | 1962 | Low | Not Rated |
| U-B Subwatershed Site 2c-1 Monona County | 34 | 1962 | Low | Not Rated |
| Uhl Dam Woodbury County | 38 | 1969 | Low | Not Rated |
| Union County Roadgrade Dam 29-73-29 Union County | 39 | 1993 | Low | Not Rated |
| Union Grove Lake Dam Tama County | 29 | 1920 | Significant | Fair |
| Union Grove Silt Containment Dam Tama County | 17 | 1990 | Low | Not Rated |
| Union Hill Wpa Dam Cerro Gordo County | 8 | 1997 | Low | Not Rated |
| Upland Investments Dam Fremont County | 23 | 2021 | Low | Not Rated |
| Upper Beaver Subwatershed Site 15-1 Monona County | 54 | 1966 | Low | Not Rated |
| Upper Beaver Subwatershed Site 20-1 Monona County | 51 | 1967 | Low | Not Rated |
| Upper Beaver Subwatershed Site 4-1 Monona County | 49 | 1968 | Low | Not Rated |
| Upper Beaver Subwatershed Site 50-1 Monona County | 49 | 1968 | Low | Not Rated |
| Upper Beaver Subwatershed Site 51-1 Monona County | 36 | 1968 | Low | Not Rated |
| Upper Beaver Subwatershed Site 6-1 Monona County | 64 | 1967 | Low | Not Rated |
| Upper Beaver Subwatershed Site M-1 Monona County | 60 | 1967 | Low | Poor |
| Upper Beaver Subwatershed Site M-2 Monona County | 43 | 1967 | Low | Not Rated |
| Upper Centerville Reservoir Dam Appanoose County | 48 | 1912 | Significant | Fair |
| Upper Locust Creek Watershed Site L-19 Wayne County | 28 | 1995 | Low | Not Rated |
Data sourced from the National Inventory of Dams (NID). Hazard classification reflects potential consequences of failure, not the likelihood of failure.