Dewey Reservoir Report
Nearby: Neiser #1 Medicine Lake Dam No. 4
Last Updated: December 20, 2025
Dewey, located in Sheridan, Montana, is a private water resource managed by the USDA NRCS with a primary purpose of fire protection, stock, or small fish pond.
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Summary
This 1948 Earth type dam stands at a height of 25 feet and has a storage capacity of 82 acre-feet, with a normal storage level of 49 acre-feet. The dam is regulated by the Montana Department of Natural Resources and Conservation, with state permitting, inspection, and enforcement in place to ensure its safe operation.
Situated in Congressional District 00 of Montana, Dewey serves as a vital resource for the community of Reserve, providing water for various purposes such as fire protection and livestock management. With a low hazard potential and a condition assessment of "Not Rated," Dewey highlights the importance of proper infrastructure maintenance and management in ensuring the sustainability of water resources in the face of climate change. As a diffused surface water source, Dewey plays a crucial role in supporting local ecosystems and enhancing overall water security in the region.
With a history dating back to 1948, Dewey continues to be a significant asset for water management in Montana, showcasing the collaboration between private ownership and government agencies in safeguarding water resources. As climate enthusiasts and water resource advocates, understanding the importance of structures like Dewey is essential in promoting sustainable water management practices and adapting to changing environmental conditions. The presence of regulatory oversight, coupled with a focus on risk assessment and emergency preparedness, underscores the commitment to maintaining the integrity and functionality of Dewey for future generations.
Year Completed |
1948 |
Dam Length |
200 |
Dam Height |
25 |
River Or Stream |
DIFFUSED SURFACE WATER |
Primary Dam Type |
Earth |
Hydraulic Height |
25 |
Drainage Area |
3.91 |
Nid Storage |
82 |
Hazard Potential |
Low |
Nid Height |
25 |
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.
Dewey