Thomas Hill Reservoir Dam
Thomas Hill Reservoir Dam is an earth dam located in Randolph County, Missouri, built in 1966. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Thomas Hill Reservoir Dam
The primary purpose of Thomas Hill Reservoir 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 Associated Electric Corp (public utility). It impounds the Middle Fork Chariton River near Thomas Hill.
The dam stands 70 feet tall and stretches 2,450 feet across, creates a reservoir covering 3,500 acres, has a maximum storage capacity of 260,458 acre-feet, and collects water from a drainage area of 146 square miles. Completed in 1966, the structure is well into its service life at over 50 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 01/10/2023.
At 70 feet, this dam is taller than 96% 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 | Randolph |
| Nearest City | Thomas Hill |
| River/Stream | Middle Fork Chariton River |
| Coordinates | 39.55104, -92.64450 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 70 ft |
| Dam Height | 70 ft |
| Dam Length | 2,450 ft |
| Year Completed | 1966 (60 years old) |
Storage & Hydraulics
| NID Storage | 260,458 acre-ft |
| Max Storage | 260,458 acre-ft |
| Normal Storage | 70,000 acre-ft |
| Surface Area | 3,500 acres |
| Drainage Area | 146 sq mi |
| Max Discharge | 12,200 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | ASSOCIATED ELECTRIC CORP |
| Owner Type | Public Utility |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 01/10/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MO10134 |
| Federal ID | MO10134 |
| More Info | State Dam Safety Program |