Jarl No.1 Reservoir Report
Nearby: Jensen No.9 Jensen No. 2
Last Updated: December 8, 2025
Jarl No.1 is a privately owned dam located in Mellette, South Dakota, along TR Cottonwood Creek offstream.
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Summary
Built in 1968, this earth dam stands at a height of 23 feet and has a storage capacity of 128 acre-feet. Managed by the Natural Resources Conservation Service, the dam has a low hazard potential and is currently rated as "Not Rated" in terms of condition assessment.
Despite its modest size, Jarl No.1 plays a crucial role in water resource management in the area, providing important storage for agricultural and environmental purposes. With a maximum discharge capacity of 132 cubic feet per second, the dam serves to regulate water flow and prevent flooding downstream. It is also subject to state regulation, inspection, and enforcement to ensure its safety and compliance with standards set by the South Dakota Department of Environment and Natural Resources.
Climate enthusiasts and water resource advocates can appreciate Jarl No.1 as an example of sustainable water infrastructure in a rural setting. Its presence highlights the importance of proper dam maintenance and monitoring, especially in regions prone to extreme weather events. By understanding the role of dams like Jarl No.1 in water management, stakeholders can work towards more resilient and environmentally conscious water resource practices in the face of a changing climate.
Year Completed |
1968 |
Dam Length |
100 |
Dam Height |
23 |
River Or Stream |
TR COTTONWOOD CREEK OFFSTREAM |
Primary Dam Type |
Earth |
Hydraulic Height |
23 |
Nid Storage |
128 |
Hazard Potential |
Low |
Nid Height |
23 |
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.
Jarl No.1