Johnson Bros 1 Reservoir Report
Last Updated: December 6, 2025
Johnson Bros 1 is a privately owned dam located in Harding, South Dakota, on Sand Creek.
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Summary
Built in 1960, this earth dam stands at a height of 15 feet and has a capacity of 75 acre-feet. With a low hazard potential and a condition assessment of "Not Rated," this dam plays a crucial role in water resource management in the area.
Managed by the South Dakota Department of Environment and Natural Resources (DENR), Johnson Bros 1 is regulated, permitted, inspected, and enforced by the state, ensuring its safety and compliance with regulations. While the dam has not been modified in recent years and lacks an Emergency Action Plan (EAP), it serves as a reliable structure for flood control and water storage in the region.
Located within the Omaha District of the US Army Corps of Engineers, Johnson Bros 1 is a significant piece of infrastructure contributing to the water management efforts in South Dakota. With a spillway width and other specific details not provided, this dam remains a key component in the conservation and utilization of water resources in the area, under the oversight of both state and federal agencies.
Year Completed |
1960 |
Dam Length |
555 |
Dam Height |
15 |
River Or Stream |
SAND CREEK |
Primary Dam Type |
Earth |
Hydraulic Height |
15 |
Nid Storage |
75 |
Hazard Potential |
Low |
Nid Height |
15 |
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.
Johnson Bros 1