Tennyson Dam Reservoir Report
Nearby: Quinn Twp Dam Quinn Dam
Last Updated: December 6, 2025
Tennyson Dam, located in Pennington, South Dakota, is a state-regulated earth dam completed in 1937.
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Summary
With a height of 20 feet and a length of 1760 feet, the dam serves the primary purpose of water storage on the TR-Bad River. It has a maximum storage capacity of 535 acre-feet, with a normal storage level of 200 acre-feet. The dam has a low hazard potential, meaning it poses minimal risk to downstream areas in the event of a failure.
Managed by the South Dakota Department of Agriculture and Natural Resources (DANR), Tennyson Dam undergoes regular inspections every three years to ensure its structural integrity and safety. The dam is not currently rated for its condition, but it meets state permitting, inspection, and enforcement requirements. In the event of an emergency, the dam has not had an Emergency Action Plan (EAP) prepared, indicating a potential area for improvement in its risk management measures. Overall, Tennyson Dam plays a crucial role in water resource management in the region, providing essential water storage for agricultural and environmental needs along the TR-Bad River.
Year Completed |
1937 |
Dam Length |
1760 |
Dam Height |
20 |
River Or Stream |
TR-BAD RIVER |
Primary Dam Type |
Earth |
Hydraulic Height |
20 |
Nid Storage |
535 |
Hazard Potential |
Low |
Nid Height |
20 |
Seasonal Comparison
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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.
Tennyson Dam