Jensen Number 7 Reservoir Report
Nearby: Jensen Number 5 Jensen No. 6
Last Updated: December 8, 2025
Jensen Number 7, a private-owned earth dam located in Mellette, South Dakota, was completed in 1969 and stands at a height of 29 feet with a length of 340 feet.
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Summary
The dam has a maximum storage capacity of 21 acre-feet and is primarily used for offstream water resource management from a branch of the Cottonwood River. Despite its relatively low hazard potential, the dam has not been rated for its condition assessment, highlighting the importance of regular inspections and maintenance to ensure its long-term functionality.
Managed by the Natural Resources Conservation Service, Jensen Number 7 is regulated by the South Dakota Department of Environment and Natural Resources. The dam is equipped with necessary state-mandated permitting, inspection, and enforcement mechanisms to ensure compliance with safety standards. With a low hazard potential, the dam plays a crucial role in water resource management in the region and serves as an essential infrastructure for maintaining water supply and mitigating potential flood risks. Climate enthusiasts and water resource stakeholders will find Jensen Number 7 to be a valuable asset in the sustainable management of water resources in South Dakota.
As a significant structure in the St. Paul District, Jensen Number 7 plays a vital role in water resource management and flood control efforts in the region. Despite its low hazard potential, regular monitoring and maintenance are essential to ensure the dam's continued functionality and safety. With its completion dating back to 1969, Jensen Number 7 stands as a testament to the importance of proper infrastructure for climate resilience and sustainable water resource management. Enthusiasts in water resources and climate will find Jensen Number 7 to be a key component in the intricate network of infrastructure that supports the region's water supply and environmental resilience.
Year Completed |
1969 |
Dam Length |
340 |
Dam Height |
29 |
River Or Stream |
TR OF COTTONWOOD OFFSTREAM |
Primary Dam Type |
Earth |
Hydraulic Height |
29 |
Nid Storage |
21 |
Hazard Potential |
Low |
Nid Height |
29 |
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.
Jensen Number 7