Lone Mountain Detention Basin Dam Reservoir Report

Last Updated: December 5, 2025

Located in North Las Vegas, Nevada, the Lone Mountain Detention Basin Dam serves as a crucial structure for flood risk reduction along the Las Vegas Wash.


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Summary

Owned and regulated by the Nevada Department of Water Resources, this earth dam stands at a height of 42 feet and has a hydraulic height of 37 feet. With a storage capacity of 744 acre-feet and a drainage area of 11.7 square miles, this dam plays a significant role in managing water flow and protecting the surrounding area from potential flooding.

The primary purpose of the Lone Mountain Detention Basin Dam is flood risk reduction, although it also serves as a fish and wildlife pond and a recreation area. Classified as a high-hazard potential structure with a fair condition assessment, this dam is equipped with an uncontrolled spillway and a single uncontrolled outlet gate. Despite its moderate risk level, regular inspections and maintenance help ensure the safety and integrity of this essential water resource infrastructure.

With its strategic location and vital role in water management, the Lone Mountain Detention Basin Dam stands as a testament to the importance of proactive flood control measures in a region susceptible to extreme weather events. As a key component of the local flood risk reduction system, this dam exemplifies the intersection of engineering ingenuity and environmental stewardship in safeguarding communities and ecosystems against the impacts of climate change.

Dam Length

3617

Dam Height

42

River Or Stream

LAS VEGAS WASH-TR

Primary Dam Type

Earth

Surface Area

44

Hydraulic Height

37

Drainage Area

11.7

Nid Storage

744

Structural Height

37

Outlet Gates

Uncontrolled - 1

Hazard Potential

High

Foundations

Rock, Soil

Nid Height

42
       
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.