Alexander Dam Reservoir Report
Nearby: Bakers Gulch Dam K. Sutton
Last Updated: December 7, 2025
Alexander Dam, located in South Dakota, is a privately owned earth dam completed in 1976 with a height of 38 feet and a length of 870 feet.
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Summary
The dam has a storage capacity of 1150 acre-feet and a maximum discharge of 2080 cubic feet per second. It is regulated by the South Dakota Department of Environment and Natural Resources, with state permitting, inspection, and enforcement in place to ensure its safety and compliance.
Despite being rated as having a low hazard potential and not currently assessed for condition, Alexander Dam plays a crucial role in water resource management in the region. With a primary purpose not specified, the dam serves various functions such as flood control, irrigation, and water supply. Situated on the TRIB. MISSONot RatedI RIVER in Sully County, the dam contributes to the overall water management efforts in the area.
While lacking detailed information on emergency action plans and risk assessments, Alexander Dam remains a key infrastructure for water resources in South Dakota. Its presence highlights the importance of monitoring and maintaining dams to ensure their safety and effectiveness in managing water resources and mitigating climate-related risks in the region.
Year Completed |
1976 |
Dam Length |
870 |
Dam Height |
38 |
River Or Stream |
TRIB. MISSONot RatedI RIVER |
Primary Dam Type |
Earth |
Hydraulic Height |
38 |
Nid Storage |
1150 |
Hazard Potential |
Low |
Nid Height |
38 |
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.
Alexander Dam