Winchell Bros. No.1 Reservoir Report
Nearby: Jensen No.1 Jensen No. 6
Last Updated: December 8, 2025
Winchell Bros.
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Summary
No.1 is a privately owned dam located in Mellette, South Dakota, with a height of 25 feet and a length of 400 feet. Completed in 1958, this earth dam serves the primary purpose of controlling the TR Cottonwood Offstream river flow and has a storage capacity of 47 acre-feet. Despite being categorized as a low hazard potential structure, its current condition is marked as "Not Rated", indicating the need for further assessment and evaluation of its safety and structural integrity.
Managed by the Natural Resources Conservation Service, Winchell Bros. No.1 is regulated by the South Dakota Department of Environment and Natural Resources (DENR) and undergoes regular permitting, inspection, and enforcement measures to ensure compliance with state regulations. The dam's location within the St. Paul District of the US Army Corps of Engineers' jurisdiction adds an additional layer of oversight and monitoring to its operations. With a normal storage capacity of 30 acre-feet and a maximum discharge rate of 84 cubic feet per second, this dam plays a crucial role in water resource management and flood control in the region.
While Winchell Bros. No.1 has not been rated for its condition assessment, its low hazard potential and the absence of a detailed emergency action plan raise questions about its preparedness for potential risks and emergencies. As climate change continues to impact water resources and infrastructure, it is essential for dam owners and regulators to prioritize the safety and resilience of structures like Winchell Bros. No.1 to safeguard communities and ecosystems from the increasing threats of extreme weather events and flooding.
Year Completed |
1958 |
Dam Length |
400 |
Dam Height |
25 |
River Or Stream |
TR COTTONWOOD OFFSTREAM |
Primary Dam Type |
Earth |
Hydraulic Height |
25 |
Nid Storage |
47 |
Hazard Potential |
Low |
Nid Height |
25 |
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.
Winchell Bros. No.1