Vern Long Reservoir Report
Nearby: Little Moreau #3 Little Moreau #1
Last Updated: December 13, 2025
Vern Long is a private dam located in Dewey, South Dakota, along the TR-MOREAU river.
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Summary
Built in 1971, this Earth-type dam stands at 27 feet high and spans 425 feet in length, with a storage capacity of 35 acre-feet. While it is regulated by the South Dakota Department of Environment and Natural Resources (DENR), it has not been rated for its condition assessment, and its hazard potential is considered low.
Despite its low hazard potential, Vern Long plays a crucial role in water resource management in the area, with a maximum discharge capacity of 1995 cubic feet per second. The dam is equipped with outlet gates, although specific details on spillway type and width are not provided. Dusty Johnson, the Representative for South Dakota, oversees this area, ensuring that the dam meets state regulatory requirements for inspection, permitting, and enforcement.
While Vern Long has not been inspected recently and lacks some key emergency preparedness measures, its presence underscores the importance of maintaining infrastructure to mitigate climate-related risks. As climate enthusiasts and water resource advocates, staying informed about the condition and management of dams like Vern Long is essential for ensuring the sustainable utilization of water resources in South Dakota.
Year Completed |
1971 |
Dam Length |
425 |
Dam Height |
27 |
River Or Stream |
TR-MOREAU |
Primary Dam Type |
Earth |
Hydraulic Height |
27 |
Nid Storage |
35 |
Hazard Potential |
Low |
Nid Height |
27 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Moreau R Near Whitehorse Sd
|
35cfs |
Grand R At Little Eagle Sd
|
47cfs |
Oak Cr Near Wakpala Sd
|
10cfs |
Moreau R Near Faith Sd
|
14cfs |
Cedar Creek Nr Raleigh
|
20cfs |
Cannonball River Nr Raleigh
|
40cfs |
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.
Vern Long