Circle C No.1 Reservoir Report
Nearby: Circle C No.2 M. Scism No.1
Last Updated: December 5, 2025
Circle C No.1 is a privately owned earth dam located in Custer, South Dakota, along the TR-CHEYENNE river.
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Summary
Built in 1951, this dam stands at 18 feet in height and spans 600 feet in length, with a storage capacity of 57 acre-feet. Managed by the Natural Resources Conservation Service, Circle C No.1 is regulated by the South Dakota Department of Environment and Natural Resources, ensuring that it meets state permitting, inspection, and enforcement standards.
Despite its low hazard potential and the fact that its condition assessment is yet to be rated, Circle C No.1 plays a crucial role in water resource management in the region. With a maximum discharge capacity of 630 cubic feet per second, this dam provides flood control and water storage benefits for the surrounding area. Additionally, its presence contributes to the overall resilience of the local ecosystem in the face of changing climate patterns.
As water resource and climate enthusiasts continue to monitor and assess the impact of climate change on water systems, structures like Circle C No.1 serve as essential components in mitigating risks and adapting to evolving environmental conditions. By upholding regulatory standards and ensuring proper maintenance, this dam remains a valuable asset in safeguarding water resources and supporting sustainable development in South Dakota.
Year Completed |
1951 |
Dam Length |
600 |
Dam Height |
18 |
River Or Stream |
TR-CHEYENNE |
Primary Dam Type |
Earth |
Hydraulic Height |
18 |
Nid Storage |
57 |
Hazard Potential |
Low |
Nid Height |
18 |
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.
Circle C No.1