Harold Arnold Reservoir Report
Last Updated: December 13, 2025
Harold Arnold is a privately owned dam located in Bullhead, South Dakota, within Corson County.
°F
°F
mph
Wind
%
Humidity
Summary
Constructed in 1950, this earth dam stands at a height of 21 feet and has a storage capacity of 210 acre-feet. Managed by the Natural Resources Conservation Service, this structure plays a crucial role in regulating water flow along the TR-GRAND river or stream.
Despite its relatively low hazard potential, Harold Arnold is regulated by the South Dakota Department of Environment and Natural Resources, with regular inspections and enforcement ensuring its safety and compliance with state regulations. While the dam's condition assessment is currently listed as "Not Rated," ongoing monitoring and maintenance efforts are likely in place to uphold its structural integrity and functionality. With a proximity of 18 miles to the St. Paul District of the US Army Corps of Engineers, Harold Arnold serves as a vital component of water resource management in the region.
Water resource and climate enthusiasts will find Harold Arnold to be a fascinating case study in private dam ownership and state regulation. Its location in the heart of South Dakota's scenic landscape, coupled with its historical significance and operational importance for water storage and regulation, make it a noteworthy site for those interested in the intersection of water management, infrastructure, and environmental conservation. As discussions around climate change and water scarcity continue to gain prominence, understanding the role of structures like Harold Arnold in maintaining resilient water systems becomes increasingly crucial for sustainable resource management in the face of evolving climatic challenges.
Year Completed |
1950 |
Dam Length |
450 |
Dam Height |
21 |
River Or Stream |
TR-GRAND |
Primary Dam Type |
Earth |
Hydraulic Height |
21 |
Nid Storage |
210 |
Hazard Potential |
Low |
Nid Height |
21 |
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.
Harold Arnold