Selvin Johnson Reservoir Report
Nearby: Veryl Schroeder 1 Veryl Schroeder 2
Last Updated: December 6, 2025
Selvin Johnson is a privately owned earth dam located in Pennington, South Dakota, along the TR Cheyenne river.
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Summary
Built in 1935, this dam stands at a height of 26 feet and has a length of 450 feet, offering a storage capacity of 80 acre-feet. While its primary purpose and associated structures are not specified, Selvin Johnson is regulated by the South Dakota Department of Environment and Natural Resources (DENR), with state permitting, inspection, and enforcement all in place.
Managed by a private owner, Selvin Johnson has a low hazard potential and a condition assessment that is currently not rated. Despite lacking specific data on spillway type, outlet gates, and inspection frequency, the dam is deemed to meet safety guidelines by authorities. Situated within the St. Paul District of the US Army Corps of Engineers, Selvin Johnson plays a crucial role in water resource management in the region, contributing to flood control and ensuring a stable water supply for local communities.
With a long history of serving the area, Selvin Johnson remains an essential infrastructure for water management in Pennington County. While additional details on its operation and maintenance may be warranted, the dam's presence underscores the importance of effective regulation and oversight in safeguarding water resources and mitigating potential risks associated with dam infrastructure in a changing climate. As water resource and climate enthusiasts, staying informed about structures like Selvin Johnson is vital for promoting sustainable practices and resilience in the face of environmental challenges.
Year Completed |
1935 |
Dam Length |
450 |
Dam Height |
26 |
River Or Stream |
TR CHEYENNE |
Primary Dam Type |
Earth |
Hydraulic Height |
26 |
Nid Storage |
80 |
Hazard Potential |
Low |
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.
Selvin Johnson