Grumpy Reservoir Report
Nearby: Sneezie Courtney Herefords #3
Last Updated: December 5, 2025
Grumpy is a privately owned earth dam located in Carter, Montana, near Marmouth South Dakota.
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Summary
Built in 1961 by the USDA NRCS, this dam serves multiple purposes including fire protection, stock, and small fish pond. With a height of 20 feet and a length of 300 feet, Grumpy has a storage capacity of 275 acre-feet and a drainage area of 0.88 square miles. It is regulated by the Montana Department of Natural Resources and Conservation (DNRC) and is inspected and enforced by the state regularly to ensure its safety and compliance with regulations.
Situated on TR-Indian Creek, Grumpy has a low hazard potential and is currently rated as "Not Rated" in terms of its condition assessment. Despite not having a condition assessment date, the dam is monitored for any potential risks and has emergency action plans in place. The dam's spillway width is 20 feet, and it has a maximum discharge capacity of 200 cubic feet per second. Grumpy's location in a critical area for water resource management and climate resilience highlights its significance in providing essential services for the surrounding community and ecosystem.
Overall, Grumpy stands as a vital infrastructure for fire protection, livestock management, and environmental conservation in the region. Its construction and maintenance are overseen by the USDA NRCS, ensuring that it continues to serve its purposes effectively while adhering to state regulations and safety standards. As a key component of the local water resource system, Grumpy plays a crucial role in mitigating potential risks and enhancing the resilience of the surrounding area to climate-related challenges.
Year Completed |
1961 |
Dam Length |
300 |
Dam Height |
20 |
River Or Stream |
TR-INDIAN CREEK |
Primary Dam Type |
Earth |
Hydraulic Height |
20 |
Drainage Area |
0.88 |
Nid Storage |
275 |
Hazard Potential |
Low |
Nid Height |
20 |
Seasonal Comparison
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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.
Grumpy