Lake Harmony Dam
Lake Harmony Dam is a gravity dam located in Madison County, Missouri, built in 1870. It carries a High hazard potential classification.
About Lake Harmony Dam
The primary purpose of Lake Harmony Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Lk Harmony Prop Own Asso (private). It impounds the Tr-little St Francois River near Fredericktown.
The dam stands 21 feet tall, creates a reservoir covering 37 acres, has a maximum storage capacity of 416 acre-feet, and collects water from a drainage area of 2,175 square miles. Completed in 1870, the structure is one of the older dams in the region, with over a century and a half 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. The most recent inspection on record was 09/05/1979. That was 46 years ago — unusually long for a high-hazard dam, which typically requires more frequent inspections.
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 | Madison |
| Nearest City | Fredericktown |
| River/Stream | Tr-little St Francois River |
| Coordinates | 37.61332, -90.29811 |
Physical Characteristics
| Dam Type | Gravity |
| NID Height | 21 ft |
| Dam Height | 21 ft |
| Year Completed | 1870 (156 years old) |
Storage & Hydraulics
| NID Storage | 416 acre-ft |
| Max Storage | 416 acre-ft |
| Normal Storage | 185 acre-ft |
| Surface Area | 37 acres |
| Drainage Area | 2,175 sq mi |
Ownership & Safety
| Purpose | Recreation |
| Owner | LK HARMONY PROP OWN ASSO |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Not Rated |
| Last Inspection | 09/05/1979 |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | MO30612 |
| Federal ID | MO30612 |
| More Info | State Dam Safety Program |