Cotter Reservoir Report
Nearby: Blunt Ranches #4 Ork
Last Updated: December 6, 2025
Cotter is a private water resource infrastructure located in Phillips County, Montana, specifically on First Creek.
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Summary
This earth dam was completed in 1950 and serves multiple purposes, including fire protection, stock watering, and creating a small fish pond. With a height of 20 feet and a length of 540 feet, Cotter has a storage capacity of 268 acre-feet and a normal storage level of 137 acre-feet, covering a surface area of 24 acres.
The dam is regulated by the Montana Department of Natural Resources and Conservation (DNRC) and is inspected, permitted, and enforced by the state agency. Despite being rated as having a low hazard potential, Cotter's condition has not been officially assessed. The emergency action plan status and risk management measures for the dam are currently not available, indicating a potential area for improvement in terms of preparedness and safety protocols.
While Cotter has not been modified in recent years and lacks specific data on drainage area or spillway type, its location and purpose make it an important resource for water supply and ecosystem support in the region. Enthusiasts of water resources and climate in Montana may find Cotter's historical significance and potential for future enhancements intriguing, especially in the context of sustainable water management and environmental conservation efforts in the area.
Year Completed |
1950 |
Dam Length |
540 |
Dam Height |
20 |
River Or Stream |
FIRST CREEK |
Primary Dam Type |
Earth |
Surface Area |
24 |
Hydraulic Height |
20 |
Nid Storage |
268 |
Hazard Potential |
Low |
Nid Height |
20 |
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.
Cotter