Summary
The dam stands at a height of 40 feet with a hydraulic height of 36 feet and a structural height of 45 feet. Its primary purpose is irrigation, serving the area with a normal storage capacity of 417 acre-feet and a surface area of 29 acres. However, the dam is currently assessed to be in poor condition with a significant hazard potential, pointing to the need for maintenance and upgrades to ensure its safety and functionality.
Managed by private owners, Flathead is subject to state regulations, permitting, inspections, and enforcement. It features an uncontrolled spillway with a width of 90 feet and three valve outlet gates. The dam's risk assessment categorizes it as moderate, highlighting the importance of implementing risk management measures to mitigate potential hazards. The last inspection in November 2017 indicated a need for improvements to bring the dam up to standard, emphasizing the necessity of ongoing monitoring and maintenance to safeguard the surrounding community and water resources.
In addition to its structural details, Flathead's location in Manderson, Wyoming, and its association with the Gomer Gulch river make it a significant water resource for the region. With its historical and hydrological importance, Flathead underscores the intersection of water management, climate resilience, and infrastructure maintenance in sustaining agricultural activities and ecological balance in the area.
Year Completed |
1979 |
Dam Length |
1600 |
Dam Height |
40 |
River Or Stream |
GOMER GULCH |
Primary Dam Type |
Earth |
Surface Area |
29 |
Hydraulic Height |
36 |
Drainage Area |
1.3 |
Nid Storage |
417 |
Structural Height |
45 |
Outlet Gates |
Valve - 3 |
Hazard Potential |
Significant |
Foundations |
Soil |
Nid Height |
45 |
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.
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