Greenfield Reservoir Dam
Greenfield Reservoir Dam is an earth dam located in Adair County, Iowa, built in 1979. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Greenfield Reservoir Dam
The primary purpose of Greenfield Reservoir Dam is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by Greenfield Municipal Utilities (local government). It impounds the Tr- Middle Nodaway R. near Greenfield.
The dam stands 42 feet tall and stretches 990 feet across, creates a reservoir covering 49 acres, has a maximum storage capacity of 1,150 acre-feet, and collects water from a drainage area of 1 square miles. Completed in 1979, the structure is 47 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 09/04/2023.
At 42 feet, this dam is taller than 89% of dams nationwide.
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 | Adair |
| Nearest City | Greenfield |
| River/Stream | Tr- Middle Nodaway R. |
| Coordinates | 41.29910, -94.48210 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 42 ft |
| Dam Height | 42 ft |
| Dam Length | 990 ft |
| Year Completed | 1979 (47 years old) |
Storage & Hydraulics
| NID Storage | 1,150 acre-ft |
| Max Storage | 1,150 acre-ft |
| Normal Storage | 612 acre-ft |
| Surface Area | 49 acres |
| Drainage Area | 1 sq mi |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Water Supply |
| Owner | Greenfield Municipal Utilities |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 09/04/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | IA02267 |
| Federal ID | IA02267 |
| More Info | State Dam Safety Program |