Round Valley Reservoir Report

Last Updated: December 5, 2025

Round Valley, also known as Round Valley Reservoir, is a privately owned dam located in Belfast, California.


°F

°F

mph

Wind

%

Humidity

Summary

Built in 1892, this earth dam stands at a height of 45 feet and has a maximum storage capacity of 5500 acre-feet, primarily serving as a water supply for irrigation purposes. With a significant hazard potential, the dam is under state regulation and inspection by the California Department of Water Resources, ensuring its structural integrity and safety.

Situated on Round Val Cr, with a drainage area of 10.6 square miles, Round Valley Reservoir covers a surface area of 420 acres and has a hydraulic height of 40.4 feet. Despite its age, the dam has been assessed as satisfactory in condition as of September 2017, with regular inspections conducted to monitor its safety. The reservoir's emergency action plan has been updated most recently in January 2021, highlighting the importance of preparedness in the event of a potential risk or emergency situation.

Owned by private entities, Round Valley plays a crucial role in providing water resources to the surrounding area, contributing to agricultural irrigation and water supply needs. With its historical significance dating back over a century, the dam stands as a testament to the importance of sustainable water management practices in the face of evolving climate challenges.

Year Completed

1892

Dam Length

220

Dam Height

45

River Or Stream

Round Val Cr

Primary Dam Type

Earth

Surface Area

420

Hydraulic Height

40.4

Drainage Area

10.6

Nid Storage

5500

Hazard Potential

Significant

Nid Height

45
       
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.