Collins Detention Reservoir Reservoir Report
Nearby: Chico Flats Lori Detention Dam
Last Updated: December 20, 2025
Collins Detention Reservoir, located in Nashua, Montana, serves as a crucial water source for fire protection, livestock, and small fish pond purposes.
°F
°F
mph
Wind
%
Humidity
Summary
Built in 1957, this private earth dam stands at a height of 27 feet with a structural height of 40.7 feet, offering a storage capacity of 1,700 acre-feet. Situated along Willow Creek in Valley County, this reservoir plays a vital role in the local ecosystem by providing water for agricultural and recreational activities.
Managed by the Montana Department of Natural Resources and Conservation (DNRC), Collins Detention Reservoir boasts a low hazard potential with a not yet rated condition assessment. Despite lacking specific inspection and emergency preparedness details, this reservoir remains a steadfast resource for the community. With its state jurisdiction and regulatory oversight, this reservoir stands as a testament to sustainable water management practices in the region.
As climate change continues to impact water resources, Collins Detention Reservoir stands as a reminder of the importance of maintaining and preserving water infrastructure for future generations. With its strategic location and multi-purpose design, this reservoir serves as a critical asset in ensuring water security and resilience in the face of evolving environmental challenges.
Year Completed |
1957 |
Dam Length |
3571 |
Dam Height |
27 |
River Or Stream |
WILLOW CREEK |
Primary Dam Type |
Earth |
Hydraulic Height |
27 |
Drainage Area |
13.62 |
Nid Storage |
1700 |
Structural Height |
40.7 |
Hazard Potential |
Low |
Nid Height |
41 |
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.
Collins Detention Reservoir