Lake Marian Dam is an earth dam located in Ste. Genevieve County, Missouri, built in 1974. It carries a High hazard potential classification.
Dam profile
NID height · 34 ft34 ft tall and 540 ft long, taller than 78% of U.S. dams with a recorded height. Height is drawn to scale against a two-story house, about 25 ft; the profile is a generic embankment section and the water level is illustrative.
About Lake Marian Dam
The primary purpose of Lake Marian Dam is recreation. The dam creates a reservoir used for recreational activities such as fishing, boating, and swimming. The dam is owned by Lake Forest Estates (private). It impounds the Tr-big Bottom Creek near Ste Genevieve.
The dam stands 34 feet tall and stretches 540 feet across, creates a reservoir covering 13 acres, has a maximum storage capacity of 195 acre-feet, and collects water from a drainage area of 177 square miles. Completed in 1974, 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. The most recent inspection on record was 07/26/1988. That was 38 years ago — unusually long for a high-hazard dam, which typically requires more frequent inspections.
At 34 feet, this dam is taller than 78% of dams nationwide.
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 | Ste. Genevieve |
| Nearest City | Ste Genevieve |
| River/Stream | Tr-big Bottom Creek |
| Coordinates | 37.94074, -90.21060 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 34 ft |
| Dam Height | 34 ft |
| Dam Length | 540 ft |
| Year Completed | 1974 (52 years old) |
Storage & Hydraulics
| NID Storage | 195 acre-ft |
| Max Storage | 195 acre-ft |
| Normal Storage | 151 acre-ft |
| Surface Area | 13 acres |
| Drainage Area | 177 sq mi |
| Max Discharge | 162 cfs |
Ownership & Safety
| Purpose | Recreation |
| Owner | Lake Forest Estates |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Not assessed |
| Last Inspection | 07/26/1988 |
| Emergency Action Plan | Not Required |
Identifiers
| NID ID | MO30655 |
| Federal ID | MO30655 |
| More Info | State Dam Safety Program |