Little River Watershed Site M-1
Little River Watershed Site M-1 is an earth dam located in Decatur County, Iowa, built in 1984. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Little River Watershed Site M-1
The primary purpose of Little River Watershed Site M-1 is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Decatur County Swcd (local government). It impounds the Little River near State Of Missouri.
The dam stands 61 feet tall and stretches 1,810 feet across, creates a reservoir covering 787 acres, has a maximum storage capacity of 32,650 acre-feet, and collects water from a drainage area of 20 square miles. Completed in 1984, the structure is 42 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 05/23/2023.
At 61 feet, this dam is taller than 95% of all dams in the United States.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Iowa dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Iowa |
| County | Decatur |
| Nearest City | State Of Missouri |
| River/Stream | Little River |
| Coordinates | 40.74820, -93.77850 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 61 ft |
| Dam Height | 61 ft |
| Dam Length | 1,810 ft |
| Year Completed | 1984 (42 years old) |
Storage & Hydraulics
| NID Storage | 32,650 acre-ft |
| Max Storage | 32,650 acre-ft |
| Normal Storage | 10,869 acre-ft |
| Surface Area | 787 acres |
| Drainage Area | 20 sq mi |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | Decatur County SWCD |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 05/23/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | IA02263 |
| Federal ID | IA02263 |
| More Info | State Dam Safety Program |