Rhead Ranch Reservoir Report

Last Updated: December 20, 2025

Rhead Ranch, located in Elmore, Idaho, is a privately owned irrigation structure regulated by the Idaho Department of Water Resources.


°F

°F

mph

Wind

%

Humidity

Summary

Completed in 1974, this earth dam on the Little Camas Creek South Fork Boise River stands at a height of 33.7 feet and has a storage capacity of 380 acre-feet. With a surface area of 32 acres and a drainage area of 41 square miles, the dam serves the primary purpose of irrigation for the surrounding agricultural lands.

Despite being classified as a low hazard potential structure with a satisfactory condition assessment, Rhead Ranch faces a moderate risk due to its location and design. The spillway, which is uncontrolled with a width of 10 feet, allows for a maximum discharge of 650 cubic feet per second. Regular inspections are conducted every 5 years to ensure the safety and functionality of the dam, with the last assessment taking place in October 2017. The emergency action plan and risk management measures for the structure are currently under review, highlighting the importance of maintaining preparedness in the face of potential climate-related challenges.

Overall, Rhead Ranch serves as a crucial water resource for agricultural activities in the area, while also facing moderate risks associated with its design and location. As water resource and climate enthusiasts, it is important to monitor and support the ongoing maintenance and regulatory efforts to ensure the safety and sustainability of this vital irrigation structure in Idaho.

Year Completed

1974

Dam Length

230

Dam Height

33.7

River Or Stream

LITTLE CAMAS CREEK SOUTH FORK BOISE RIVER

Surface Area

32

Hydraulic Height

26.7

Drainage Area

41

Nid Storage

380

Hazard Potential

Low

Foundations

Rock, Soil

Nid Height

34
       
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.