Long Branch Dam
Long Branch Dam is an earth dam located in Macon County, Missouri, built in 1978. It carries a High hazard potential classification.
About Long Branch Dam
The primary purpose of Long Branch 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 Usace - Kansas City District (federal). It impounds the East Fork Little Chariton near Macon.
The dam stands 80 feet tall and stretches 3,800 feet across, creates a reservoir covering 2,430 acres, has a maximum storage capacity of 98,000 acre-feet, and collects water from a drainage area of 109 square miles. Completed in 1978, the structure is 48 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. An emergency action plan is in place for this dam. The most recent inspection on record was 07/17/2024.
At 80 feet, this dam is taller than 97% 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 Missouri 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 | Missouri |
| County | Macon |
| Nearest City | Macon |
| River/Stream | East Fork Little Chariton |
| Coordinates | 39.75078, -92.51438 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 80 ft |
| Dam Length | 3,800 ft |
| Year Completed | 1978 (48 years old) |
Storage & Hydraulics
| NID Storage | 98,000 acre-ft |
| Max Storage | 98,000 acre-ft |
| Normal Storage | 35,000 acre-ft |
| Surface Area | 2,430 acres |
| Drainage Area | 109 sq mi |
| Max Discharge | 5,570 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | USACE - Kansas City District |
| Owner Type | Federal |
| Hazard Classification | High |
| Condition Assessment | Not Available |
| Last Inspection | 07/17/2024 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MO11176 |
| Federal ID | MO11176 |
| More Info | State Dam Safety Program |