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 1826–1850 of 3,759
| Dam Name | Height (ft) | Year | Hazard | Condition |
|---|---|---|---|---|
| Mason1 Dam Madison County | 24 | 2004 | Low | Not Rated |
| Masek Dam Winneshiek County | 25 | 2001 | Low | Not Rated |
| Marywood Farms Wetland Dam #2 Warren County | 8 | 2007 | Low | Not Rated |
| Marywood Farms Wetland Dam Warren County | 12 | 2007 | Low | Not Rated |
| Marywood Farms Dam Warren County | 35 | 1966 | Low | Not Rated |
| Martins Dam Crawford County | 23 | 1966 | Low | Not Rated |
| Martin Dam Dallas County | 27 | 1964 | Low | Not Rated |
| Marsh Dam Taylor County | 30 | 1990 | Low | Not Rated |
| Marshall Dam Montgomery County | 33 | 1989 | Low | Not Rated |
| Marr Park Dam Washington County | 24 | 1994 | Low | Not Rated |
| Marlay Dam Van Buren County | 27 | 1999 | Low | Not Rated |
| Mark Maeder Dam Adair County | 34 | 2020 | Low | Not Rated |
| Mariposa Lake Dam Jasper County | 25 | 1952 | Low | Fair |
| Marion County Roadgrade Dam 35-77-21 Marion County | 44 | 1971 | Low | Not Rated |
| Marion County Roadgrade Dam 25-76-19 Marion County | 47 | 1964 | Low | Not Rated |
| Marion County Roadgrade Dam Marion County | 37 | 1965 | Low | Not Rated |
| Marion Co. Care Facility Dam Marion County | 32 | 1985 | Low | Not Rated |
| Marengo Golf & Country Club Dam Iowa County | 33 | 2000 | Low | Not Rated |
| Marble Rock Milldam Floyd County | 15 | 1913 | Low | Not Rated |
| Marak Dam Johnson County | 30 | 1970 | Low | Not Rated |
| Manser Dam Warren County | 37 | 1983 | Low | Not Rated |
| Manor Dam Jefferson County | 26 | 1997 | Low | Not Rated |
| Manneter Dam Hardin County | 28 | 1997 | Low | Not Rated |
| Mandolfo Dam Mills County | 26 | 1990 | Low | Not Rated |
| Manchester Milldam Delaware County | 11 | 1905 | Low | Not Rated |
Data sourced from the National Inventory of Dams (NID). Hazard classification reflects potential consequences of failure, not the likelihood of failure.