Lac Marseilles Dam
Lac Marseilles Dam is an earth dam located in St. Francois County, Missouri, built in 1971. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Lac Marseilles Dam
The primary purpose of Lac Marseilles Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Terre Du Lac Poa (private). It impounds the Tr-big River near Leadwood.
The dam stands 69 feet tall and stretches 1,185 feet across, creates a reservoir covering 56 acres, has a maximum storage capacity of 1,900 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 1971, 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 12/08/2021.
At 69 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 | St. Francois |
| Nearest City | Leadwood |
| River/Stream | Tr-big River |
| Coordinates | 37.89478, -90.62185 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 69 ft |
| Dam Height | 69 ft |
| Dam Length | 1,185 ft |
| Year Completed | 1971 (55 years old) |
Storage & Hydraulics
| NID Storage | 1,900 acre-ft |
| Max Storage | 1,900 acre-ft |
| Normal Storage | 1,900 acre-ft |
| Surface Area | 56 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 2,400 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Recreation |
| Owner | TERRE DU LAC POA |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 12/08/2021 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | MO30282 |
| Federal ID | MO30282 |
| More Info | State Dam Safety Program |