Piggs No.1 Reservoir Report
Last Updated: December 13, 2025
Piggs No.1 is a privately owned dam located in Mellette, South Dakota, along the tributary of the White River.
°F
°F
mph
Wind
%
Humidity
Summary
Built in 1969, this earth dam stands at 26 feet high and stretches 415 feet in length, with a storage capacity of 28 acre-feet. Despite being a low hazard potential structure, it is still regulated by the South Dakota Department of Environment and Natural Resources (DENR), with state permitting, inspection, and enforcement procedures in place to ensure its safety and compliance.
The dam's primary purpose and associated structures are not specified in the data, but its condition is categorized as "Not Rated," suggesting a need for further assessment. Piggs No.1 does not have an Emergency Action Plan (EAP) prepared, and its risk assessment and management measures are also unspecified. The dam's location within the St. Paul District of the US Army Corps of Engineers (USACE) adds a layer of federal oversight, even though it is privately owned and funded.
With a maximum discharge capacity of 635 cubic feet per second, Piggs No.1 plays a crucial role in managing water resources in the area, particularly in times of heavy rainfall or flooding. While it may not pose a significant risk at present, ongoing monitoring and maintenance are essential to ensure the safety and integrity of this important water infrastructure asset for the community and the environment.
Year Completed |
1969 |
Dam Length |
415 |
Dam Height |
26 |
River Or Stream |
TRIB. WHITE RIVER |
Primary Dam Type |
Earth |
Hydraulic Height |
26 |
Nid Storage |
28 |
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.
Piggs No.1