Atkinson No.1 Reservoir Report
Nearby: Jensen No.1 Jensen Number 1
Last Updated: December 8, 2025
Atkinson No.1 is a privately owned dam located in Mellette, South Dakota, along the tributary of Cottonwood Creek.
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Summary
Built in 1969, this earth dam stands at a height of 28 feet with a hydraulic height of 25 feet and a length of 390 feet. It has a storage capacity of 22 acre-feet and a maximum discharge of 110 cubic feet per second. Despite its low hazard potential, the dam's condition is currently not rated, highlighting the need for further assessment and monitoring.
The South Dakota Department of Environment and Natural Resources (DENR) regulates Atkinson No.1, overseeing its permitting, inspections, and enforcement. The dam is under state jurisdiction and is subject to regular state inspections to ensure its structural integrity and safety. Although there are no associated structures or emergency action plan prepared for this dam, its location and design indicate a crucial role in water resource management in the area. With its historical significance and continued importance in water storage, Atkinson No.1 serves as a key feature in the region's water infrastructure.
Overall, Atkinson No.1 provides a fascinating glimpse into the intersection of water resource management, climate considerations, and dam safety. As a part of the St. Paul District, this dam contributes to the local ecosystem and water supply by regulating flow along Cottonwood Creek. While its current condition assessment is pending, its presence underscores the need for ongoing maintenance and monitoring to ensure the safety of surrounding communities and the efficient management of water resources in South Dakota.
Year Completed |
1969 |
Dam Length |
390 |
Dam Height |
28 |
River Or Stream |
TRIB. COTTONWOOD CREEK |
Primary Dam Type |
Earth |
Hydraulic Height |
25 |
Nid Storage |
22 |
Hazard Potential |
Low |
Nid Height |
28 |
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.
Atkinson No.1