Heart Butte Dam
Heart Butte Dam is an earth dam located in Grant County, North Dakota, built in 1949. It carries a High hazard potential classification.
About Heart Butte Dam
The primary purpose of Heart Butte Dam 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 Bureau Of Reclamation (federal). It impounds the Heart River near Mandan.
The dam stands 142 feet tall and stretches 1,850 feet across, creates a reservoir covering 10,953 acres, has a maximum storage capacity of 451,200 acre-feet, and collects water from a drainage area of 1,714 square miles. Completed in 1949, the structure is well-established, with more than 75 years of service.
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. An emergency action plan is in place for this dam. The most recent inspection on record was 08/31/2022.
At 142 feet, this dam is taller than 99% 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 North Dakota 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 | North Dakota |
| County | Grant |
| Nearest City | Mandan |
| River/Stream | Heart River |
| Coordinates | 46.59670, -101.81050 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 142 ft |
| Dam Height | 142 ft |
| Dam Length | 1,850 ft |
| Year Completed | 1949 (77 years old) |
Storage & Hydraulics
| NID Storage | 451,200 acre-ft |
| Max Storage | 451,200 acre-ft |
| Normal Storage | 75,785 acre-ft |
| Surface Area | 10,953 acres |
| Drainage Area | 1,714 sq mi |
| Max Discharge | 5,700 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | BUREAU OF RECLAMATION |
| Owner Type | Federal |
| Hazard Classification | High |
| Condition Assessment | Not Available |
| Last Inspection | 08/31/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | ND00149 |
| Federal ID | ND00149 |
| More Info | State Dam Safety Program |