Green Valley Lake Reservoir Report

Last Updated: December 5, 2025

Green Valley Lake, located in Running Springs, California, is a private multi-arch dam built in 1925 for water supply purposes.


°F

°F

mph

Wind

%

Humidity

Summary

The dam stands at a height of 56 feet with a hydraulic height of 53 feet, spanning 425 feet in length. With a storage capacity of 250 acre-feet and a surface area of 22 acres, the dam serves as both a recreational area and a vital water source for the region.

Managed by the California Department of Water Resources, Green Valley Lake is regulated, permitted, inspected, and enforced by state agencies to ensure its safety and functionality. Despite its low hazard potential and satisfactory condition assessment, the dam undergoes regular inspections to mitigate any risks. The surrounding Green Valley Creek and its drainage area of 1.2 square miles contribute to the dam's importance in maintaining water supply and flood control in the area.

With its historical significance and critical role in water management, Green Valley Lake is a valuable asset in San Bernardino County, California. Climate and water resource enthusiasts can appreciate the engineering and environmental efforts put into maintaining this essential infrastructure for both human and natural ecosystems.

Year Completed

1925

Dam Length

425

Dam Height

56

River Or Stream

Green Valley Cr

Primary Dam Type

Multi-Arch

Surface Area

22

Hydraulic Height

53

Drainage Area

1.2

Nid Storage

250

Hazard Potential

Low

Nid Height

56
       
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.