Peacock No.1 Reservoir Report
Last Updated: December 13, 2025
Peacock No.1 is a privately owned dam located in Mellette, South Dakota, with a low hazard potential and a height of 27 feet.
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Summary
Constructed in 1955, this earth dam has a storage capacity of 32 acre-feet and serves as an offstream structure for TR Oak Creek. The dam is regulated by the South Dakota Department of Environment and Natural Resources (DENR), with state permitting, inspection, and enforcement in place to ensure its safety and compliance with regulations.
Although not rated for condition assessment, Peacock No.1 remains a vital component of the local water resource infrastructure, offering flood control benefits and water storage capacity. With a maximum discharge of 115 cubic feet per second, the dam provides crucial support for managing water flow in the area. As a part of the St. Paul District under the US Army Corps of Engineers, Peacock No.1 contributes to the overall water management efforts in the region, reflecting a commitment to sustainable water resource practices and climate resilience.
Year Completed |
1955 |
Dam Length |
326 |
Dam Height |
27 |
River Or Stream |
TR OAK CREEK OFFSTREAM |
Primary Dam Type |
Earth |
Hydraulic Height |
27 |
Nid Storage |
32 |
Hazard Potential |
Low |
Nid Height |
27 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
White River Near White River
|
42cfs |
Little White R Below White River Sd
|
141cfs |
White R Near Oacoma Sd
|
105cfs |
Keya Paha R Near Keyapaha Sd
|
33cfs |
Little White R Near Rosebud Sd
|
96cfs |
Bad R Near Fort Pierre Sd
|
7cfs |
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.
Peacock No.1