Glen Holloway Reservoir Report
Nearby: Don Farlee G. Holloway
Last Updated: December 7, 2025
Glen Holloway is a private earth dam located in Dewey, South Dakota, along the TR MOREAU river.
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Summary
Built in 1947, this dam stands at a height of 21 feet and has a storage capacity of 60 acre-feet. While it is not Associated with any federal agencies, the dam falls under state regulation and is subject to inspection, permitting, and enforcement by the South Dakota Department of Environment and Natural Resources (DENR).
Despite its low hazard potential and "Not Rated" condition assessment, Glen Holloway plays a crucial role in water resource management in the region by providing flood control and water storage capabilities. With a maximum discharge capacity of 4880 cubic feet per second, the dam helps mitigate the impact of heavy rainfall events and ensures a stable water supply for agricultural and municipal use.
Although the dam has not been assessed for emergency preparedness and risk management measures, its historical significance and contribution to the local water infrastructure make it an essential structure for climate enthusiasts and water resource managers to monitor and maintain in the face of changing climate conditions and increasing water demands.
Year Completed |
1947 |
Dam Length |
270 |
Dam Height |
21 |
River Or Stream |
TR MOREAU |
Primary Dam Type |
Earth |
Hydraulic Height |
21 |
Nid Storage |
60 |
Hazard Potential |
Low |
Nid Height |
21 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Moreau R Near Whitehorse Sd
|
35cfs |
Moreau R Near Faith Sd
|
14cfs |
Cheyenne R Near Plainview Sd
|
0cfs |
Grand R At Little Eagle Sd
|
47cfs |
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.
Glen Holloway