Orange County Reservoir

Orange County Reservoir is an earth dam located in Orange County, California, built in 1941. It carries a Low hazard potential classification and has a satisfactory condition assessment.

About Orange County Reservoir

The primary purpose of Orange County Reservoir is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by Metropolitan Water District Of Southern California (public utility). It impounds the Tr Fullerton Cr.

The dam stands 103 feet tall and stretches 655 feet across, creates a reservoir covering 7 acres, has a maximum storage capacity of 217 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 1941, the structure is well-established, with more than 75 years of service.

This dam has a low hazard potential classification, meaning that failure would cause minimal damage, limited primarily to the dam owner's property, with no expected loss of life. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 08/13/2025.

At 103 feet, this dam is taller than 98% of all dams in the United States.

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Low HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateCalifornia
CountyOrange
River/StreamTr Fullerton Cr
Coordinates33.93670, -117.88420

Physical Characteristics

Dam TypeEarth
NID Height103 ft
Dam Height103 ft
Dam Length655 ft
Year Completed1941 (85 years old)

Storage & Hydraulics

NID Storage217 acre-ft
Max Storage217 acre-ft
Surface Area7 acres
Drainage Area0 sq mi

Ownership & Safety

PurposeWater Supply
OwnerMetropolitan Water District Of Southern California
Owner TypePublic Utility
Hazard ClassificationLow
Condition AssessmentSatisfactory
Last Inspection08/13/2025
Emergency Action PlanYes

Identifiers

NID IDCA00218
Federal IDCA00218
More InfoState Dam Safety Program

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