Coibson #1 Reservoir Report
Nearby: Crow #32 J R Scott #12
Last Updated: December 5, 2025
Coibson #1 is a privately owned dam located in Big Horn, Montana, near the city of Hardin.
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Summary
Completed in 1955, this earthen dam stands at a height of 18 feet and serves multiple purposes including fire protection, stock watering, and creating a small fish pond. With a storage capacity of 108 acre-feet, the dam is primarily regulated by the Montana Department of Natural Resources and Conservation (DNRC) and is under state jurisdiction for permitting, inspection, and enforcement.
Situated on TR-Little Woody Creek, Coibson #1 is classified as having a low hazard potential and is currently rated as "Not Rated" in terms of condition assessment. Despite lacking detailed information on its condition, the dam continues to provide essential services for the local community, such as protecting against wildfires and providing water for livestock. With its location in a rural area and minimal associated structures, Coibson #1 is a key feature in the region's water resource infrastructure, showcasing the importance of responsible dam management for climate and water resource enthusiasts.
Although Coibson #1 has not been updated or inspected in recent years, its presence on Little Woody Creek highlights the significance of small-scale dams in supporting local ecosystems and water management practices. As climate change continues to impact water resources, understanding the condition and regulation of dams like Coibson #1 is crucial for ensuring the safety and sustainability of these structures in the face of evolving environmental challenges.
Year Completed |
1955 |
Dam Length |
275 |
Dam Height |
18 |
River Or Stream |
TR-LITTLE WOODY CREEK |
Primary Dam Type |
Earth |
Hydraulic Height |
18 |
Nid Storage |
108 |
Hazard Potential |
Low |
Nid Height |
18 |
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.
Coibson #1