Mary's Lake Dam Reservoir Report
Last Updated: December 6, 2025
Mary's Lake Dam, located in Perry County, Missouri, is a privately owned earth dam constructed in 1962 for the primary purpose of recreation.
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Summary
Standing at a height of 30 feet, the dam has a storage capacity of 209 acre-feet and serves the South Fork Saline Creek. With a surface area of 13 acres and a drainage area of 300 square miles, Mary's Lake Dam provides a picturesque and tranquil setting for outdoor enthusiasts to enjoy various recreational activities.
Despite its low hazard potential and current "Not Rated" condition assessment, Mary's Lake Dam does not fall under state regulation or inspection. This idyllic spot in St. Mary's, Missouri, offers a serene escape for visitors seeking to immerse themselves in nature and the calming waters of the lake. With a lack of associated structures and a focus on recreational use, Mary's Lake Dam stands as a testament to the harmonious coexistence of human enjoyment and environmental stewardship.
As a beloved landmark in the region, Mary's Lake Dam continues to attract water resource and climate enthusiasts who appreciate its role in providing a sanctuary for wildlife and a haven for outdoor recreation. While its maintenance and oversight may not be under state jurisdiction, the dam remains a symbol of the community's commitment to preserving natural beauty and promoting sustainable practices in a rapidly changing world.
Year Completed |
1962 |
Dam Height |
30 |
River Or Stream |
TR SOUTH FORK SALINE CREEK |
Primary Dam Type |
Earth |
Surface Area |
13 |
Drainage Area |
300 |
Nid Storage |
209 |
Structural Height |
30 |
Hazard Potential |
Low |
Foundations |
Unlisted/Unknown |
Nid Height |
30 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Dam Data Reference
Condition Assessment
SatisfactoryNo existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
Fair
No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action. Note: Rare or extreme event is defined by the regulatory agency based on their minimum
Poor A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency. Investigations and studies are necessary.
Unsatisfactory
A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
Not Rated
The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Not Available
Dams for which the condition assessment is restricted to approved government users.
Hazard Potential Classification
HighDams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
Significant
Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environment damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
Low
Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
Undetermined
Dams for which a downstream hazard potential has not been designated or is not provided.
Not Available
Dams for which the downstream hazard potential is restricted to approved government users.
Mary's Lake Dam