Little Joe Detention Reservoir Report

Last Updated: December 5, 2025

Little Joe Detention is a federal-owned structure located in Washakie, Wyoming, designed and regulated by the Bureau of Land Management.


°F

°F

mph

Wind

%

Humidity

Summary

Completed in 2003, this gravity dam on the Hampton Draw Big Horn River stands at a structural height of 25 feet and has a hydraulic height of 20 feet. With a normal storage capacity of 40.02 acre-feet and a maximum storage of 204.1 acre-feet, it serves various purposes beyond flood control and water supply.

Despite its low hazard potential, Little Joe Detention is in poor condition and is inspected every five years. The dam has an uncontrolled spillway with a width of 2 feet and a length of 657 feet, serving as a vital infrastructure for managing water resources in the region. With a moderate risk assessment rating, there is a need for ongoing risk management measures to ensure the safety and efficiency of this critical water management structure.

Located in Worland, WY, Little Joe Detention underscores the importance of maintaining and upgrading aging water infrastructure to adapt to changing climate conditions and enhance water resource management. As a key component of the water infrastructure network in Wyoming, it highlights the critical role of federal agencies like the Bureau of Land Management in overseeing, funding, and maintaining essential water resources facilities for the benefit of communities and ecosystems in the region.

Year Completed

2003

Dam Length

657

River Or Stream

HAMPTON DRAW BIG HORN RIVER

Primary Dam Type

Gravity

Surface Area

18.4

Hydraulic Height

20

Drainage Area

3100

Nid Storage

204.1

Structural Height

25

Hazard Potential

Low

Foundations

Unlisted/Unknown

Nid Height

25
       
Seasonal Comparison

Weather Forecast

Dam Data Reference

Condition Assessment

Satisfactory
No 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

High
Dams 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.