Horsley Draw Stock Reservoir Report
Last Updated: December 5, 2025
Horsley Draw Stock is a privately owned earth dam located in Sheridan, Wyoming, constructed in 1939 by designer Thomas D.
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Summary
Crank. The dam serves multiple purposes including fire protection, stock watering, and small fish pond management. With a height of 23 feet and a length of 300 feet, the dam has a normal storage capacity of 57 acre-feet and covers a surface area of 8 acres.
Despite its low hazard potential, the dam is currently in poor condition as assessed during the last inspection in September 2019. The dam has a moderate risk rating and a history of infrequent inspections every 5 years. The spillway type is uncontrolled with a width of 70 feet, and the dam is located on the Horsley Draw stream, with a drainage area of 2.6 square miles. The dam's purpose, location, and design make it an interesting case study for water resource and climate enthusiasts interested in earth dam structures and their management in Wyoming.
Overall, Horsley Draw Stock represents a unique example of a privately owned dam with multiple functions serving the local community. Its historical significance, design features, and current condition present opportunities for further research and monitoring to ensure its continued safety and effectiveness for fire protection, stock watering, and small fish pond management in the region.
Year Completed |
1939 |
Dam Length |
300 |
Dam Height |
23 |
River Or Stream |
HORSLEY DRAW |
Primary Dam Type |
Earth |
Surface Area |
8 |
Hydraulic Height |
20 |
Drainage Area |
2.6 |
Nid Storage |
57 |
Structural Height |
23 |
Outlet Gates |
None |
Hazard Potential |
Low |
Foundations |
Soil |
Nid Height |
23 |
Seasonal Comparison
Weather Forecast
Nearby Streamflow Levels
Clear Creek Near Arvada
|
256cfs |
Prairie Dog Creek Near Acme
|
19cfs |
Tongue River At State Line Nr Decker Mt
|
195cfs |
Tongue River At Tongue R Dam Nr Decker Mt
|
118cfs |
Powder River At Arvada
|
156cfs |
Goose Creek Near Acme
|
123cfs |
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.
Horsley Draw Stock