Gem Lake Dam Reservoir Report
Nearby: Glenwilfern Lake Dam Crystal Lake Dam
Last Updated: December 21, 2025
Gem Lake Dam, located in Eureka, Missouri, is a privately owned Earth dam primarily built for recreation purposes.
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Summary
Completed in 1960, this dam stands at a height of 37.8 feet and has a storage capacity of 31 acre-feet. It is situated on the TR TO LA BARQUE CREEK and is under the regulatory jurisdiction of the state of Missouri.
Despite its low hazard potential and satisfactory condition assessment, Gem Lake Dam is subject to state permitting, inspection, and enforcement to ensure its safety and functionality. The dam's construction and operation do not involve any federal agencies, making it a locally managed water resource. With its serene surroundings and recreational opportunities, the dam serves as a vital asset for the community while also contributing to the overall water management efforts in the region.
Water resource and climate enthusiasts can appreciate Gem Lake Dam for its role in providing recreational opportunities in the area, while also acknowledging the importance of its regulatory oversight and maintenance. As a privately owned structure, the dam symbolizes the collaboration between private entities and state agencies in managing water resources effectively. Its location in Jefferson County, Missouri, adds to the diverse landscape of water infrastructure within the region, making it a noteworthy site for those interested in the intersection of water management and environmental stewardship.
Year Completed |
1960 |
Dam Height |
37.8 |
River Or Stream |
TR TO LA BARQUE CREEK |
Primary Dam Type |
Earth |
Surface Area |
2 |
Drainage Area |
19 |
Nid Storage |
31 |
Structural Height |
29 |
Hazard Potential |
Low |
Foundations |
Unlisted/Unknown |
Nid Height |
38 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Meramec River At Pacific
|
557cfs |
Big River At Byrnesville
|
176cfs |
Meramec River Near Eureka
|
858cfs |
Kiefer Creek Near Ballwin
|
1cfs |
Williams Creek Near Peerless Park
|
1cfs |
Bonhomme Creek Near Ellisville
|
0cfs |
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.
Gem Lake Dam