Petri Dam; Robert Reservoir Report
Nearby: Hamann Dam Swenson Fish Dam; Kent
Last Updated: December 6, 2025
Petri Dam, also known as Robert Dam, is located in Medora, North Dakota, and was completed in 1964 by the US Forest Service.
°F
°F
mph
Wind
%
Humidity
Summary
This earth dam stands at a height of 12.7 feet and has a structural height of 16 feet, with a length of 161 feet. It serves multiple purposes including fire protection, stock watering, and as a small fish pond, with a storage capacity of 50 acre-feet and a surface area of 1.5 acres.
The dam is situated on Third Creek-TR, in Slope County, North Dakota, and is owned by the federal government. It has a spillway width of 68 feet and is classified as having a low hazard potential with a moderate risk assessment. Despite not being state regulated or permitted, the dam is inspected by federal agencies and enforces necessary safety measures to ensure its structural integrity and functionality for its various purposes.
For water resource and climate enthusiasts, Petri Dam serves as a vital structure in the region for water management and conservation efforts. Its multiple uses, low hazard potential, and moderate risk assessment make it a key component in the local ecosystem and a valuable asset for fire protection and agriculture in the area.
Year Completed |
1964 |
Dam Length |
161 |
Dam Height |
12.7 |
River Or Stream |
THIRD CREEK-TR |
Primary Dam Type |
Earth |
Surface Area |
1.5 |
Drainage Area |
0.69 |
Nid Storage |
50 |
Structural Height |
16 |
Outlet Gates |
None |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
16 |
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.
Petri Dam; Robert