Larson No. 1 Reservoir Report
Nearby: Novey No.4 Novey Joe Number 1
Last Updated: December 7, 2025
Larson No.
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Summary
1 is a privately owned earth dam located in Mellette, South Dakota, along the Round Up Creek tributary. Built in 1964, this dam stands at a height of 29 feet and has a storage capacity of 16 acre-feet, with a normal storage level of 10 acre-feet. While the dam is not rated for its condition, it is categorized as having a low hazard potential.
Managed by the South Dakota Department of Environment and Natural Resources (DENR), Larson No. 1 is subject to state regulation, permitting, inspection, and enforcement. The dam's primary purpose and associated structures are not specified, but it serves as a critical infrastructure for water resource management in the area. The dam's location within St. Paul District and its proximity to Dusty Johnson's congressional district further highlights its significance in the region.
Although details such as spillway type, outlet gates, and emergency action plans are not provided for Larson No. 1, the dam's presence underscores the importance of maintaining water resources and infrastructure in the face of climate change and increasing water demands. Water resource and climate enthusiasts can appreciate the role of dams like Larson No. 1 in ensuring water security and flood protection for communities in South Dakota.
Year Completed |
1964 |
Dam Length |
240 |
Dam Height |
29 |
River Or Stream |
TRIB.-ROUND UP CREEK |
Primary Dam Type |
Earth |
Hydraulic Height |
29 |
Nid Storage |
16 |
Hazard Potential |
Low |
Nid Height |
29 |
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.
Larson No. 1