White Rock Lake Reservoir Report

Last Updated: December 5, 2025

White Rock Lake, located in California's Nevada County, is a private hydroelectric dam with a rich history dating back to 1855.


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Summary

The dam stands at 13.5 feet tall and has a capacity of 850 acre-feet, providing power through its earth dam structure on White Rock Creek. With a surface area of 90 acres and a drainage area of 1.2 square miles, the dam plays a crucial role in water resource management and climate resilience in the region.

Managed by the Federal Energy Regulatory Commission, White Rock Lake has a low hazard potential and a moderate risk assessment. Despite its age, the dam is regularly inspected and meets regulatory standards for state permitting, inspection, and enforcement. The dam's uncontrolled spillway and 40-foot spillway width ensure efficient water flow and safety measures in case of emergencies. With its location in the beautiful Hobart Hills and its vital role in hydroelectric power generation, White Rock Lake is a fascinating site for water resource and climate enthusiasts to explore and learn about the intersection of infrastructure and environmental stewardship.

Year Completed

1855

Dam Length

274

Dam Height

13

River Or Stream

White Rock Creek

Primary Dam Type

Earth

Surface Area

90

Hydraulic Height

9.5

Drainage Area

1.2

Nid Storage

850

Structural Height

13.5

Hazard Potential

Low

Nid Height

14
       
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.