Mollman Dam Reservoir Report
Nearby: George Jesfjeld Simpson Bros.
Last Updated: December 6, 2025
Mollman Dam, located in Perkins, South Dakota, is a private earth dam completed in 2002 with a height of 26 feet and a storage capacity of 56 acre-feet.
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Summary
The dam is situated on the TR S. Fork Grand River and is regulated by the South Dakota Department of Agriculture and Natural Resources. While the dam has a low hazard potential, it has a moderate risk assessment rating of 3.
Managed by the USDA NRCS, Mollman Dam serves as a vital water resource infrastructure in the region, providing irrigation water for agricultural purposes and helping to control flooding along the Grand River. With a maximum discharge capacity of 675 cubic feet per second and an uncontrolled spillway, the dam plays a crucial role in water management in the area. Despite its importance, the dam's condition assessment remains unrated as of the last inspection in 2004.
For water resource and climate enthusiasts, Mollman Dam represents a fascinating example of sustainable water management practices in South Dakota. With its earth construction and soil foundation, the dam showcases the importance of innovative engineering solutions in ensuring water security for both agricultural and environmental needs. As efforts continue to monitor and maintain the dam's integrity, Mollman Dam stands as a key piece of infrastructure contributing to the resilience of the local water supply and ecosystem.
Year Completed |
2002 |
Dam Length |
230 |
Dam Height |
26 |
River Or Stream |
TR S. FORK GRAND RIVER |
Primary Dam Type |
Earth |
Hydraulic Height |
26 |
Nid Storage |
56 |
Outlet Gates |
None |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
26 |
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.
Mollman Dam