Hansen Marsh Reservoir Report
Nearby: Fork Wpa West Chain Lake Dam
Last Updated: December 13, 2025
Hansen Marsh, located in Ramsey, North Dakota, is a federal-owned structure designed by DU and regulated by the NDSWC.
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Summary
Built in 2002 for flood risk reduction, this earth dam stands at a height of 7.5 feet with a length of 2775 feet. The dam has a storage capacity of 452.7 acre-feet and covers a surface area of 82.4 acres, serving a drainage area of 0.3 square miles.
With a spillway width of 50 feet and an uncontrolled spillway type, Hansen Marsh has a low hazard potential and is currently rated as not assessed in terms of condition. Despite its moderate risk level, the dam has not been inspected recently and lacks an emergency action plan. However, with vertical lift outlet gates and a focus on flood risk reduction, Hansen Marsh plays a crucial role in water resource management in the area. Enthusiasts of water resources and climate will find this structure to be an important piece of infrastructure in North Dakota.
Year Completed |
2002 |
Dam Length |
2775 |
Dam Height |
7.5 |
River Or Stream |
CALIO COULEE-OS |
Primary Dam Type |
Earth |
Surface Area |
82.4 |
Drainage Area |
0.3 |
Nid Storage |
452.7 |
Structural Height |
8 |
Outlet Gates |
Vertical Lift - 1 |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
8 |
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.
Hansen Marsh
Dry Lake Near Penn