Summary
Located in Hill County near Marietta Coulee, the reservoir has a dam height of 20 feet and a storage capacity of 124 acre-feet. With a low hazard potential and a condition assessment that is not rated, the reservoir serves as a vital resource for water storage and conservation in the region.
Managed by the Montana Department of Natural Resources and Conservation (DNRC), U N Reservoir is regulated by the state and undergoes regular inspections and enforcement measures to ensure its safety and integrity. Although not operated by a federal agency, the reservoir plays a crucial role in providing water for irrigation, livestock, and emergency fire suppression. With its location in a remote area with no associated town, the reservoir serves as a valuable asset for the local community and surrounding areas.
As a key component of the water infrastructure in Montana, U N Reservoir is essential for maintaining water supply and supporting various agricultural and environmental needs. With its historical significance dating back to the 1940s, the reservoir continues to play a vital role in water resource management and climate resilience efforts in the region.
Year Completed |
1940 |
Dam Length |
1100 |
Dam Height |
20 |
River Or Stream |
MARIETTA COULEE |
Primary Dam Type |
Earth |
Hydraulic Height |
20 |
Nid Storage |
124 |
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.
U N Reservoir