Copper Basin

Copper Basin is an arch dam located in San Bernardino County, California, built in 1938. It carries a High hazard potential classification and has a satisfactory condition assessment.

About Copper Basin

The primary purpose of Copper Basin 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 Copper Basin near Parker Strip.

The dam stands 184 feet tall and stretches 265 feet across, creates a reservoir covering 427 acres, has a maximum storage capacity of 22,000 acre-feet, and collects water from a drainage area of 8 square miles. Completed in 1938, the structure is well-established, with more than 75 years of service.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. 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 10/09/2025.

At 184 feet, this dam is taller than 99% of all dams in the United States.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The California dam safety program can provide more specific information about emergency planning for this structure.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.

High HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateCalifornia
CountySan Bernardino
Nearest CityParker Strip
River/StreamCopper Basin
Coordinates34.27900, -114.22270

Physical Characteristics

Dam TypeArch
NID Height184 ft
Dam Height184 ft
Dam Length265 ft
Year Completed1938 (88 years old)

Storage & Hydraulics

NID Storage22,000 acre-ft
Max Storage22,000 acre-ft
Surface Area427 acres
Drainage Area8 sq mi

Ownership & Safety

PurposeWater Supply
OwnerMetropolitan Water District Of Southern California
Owner TypePublic Utility
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection10/09/2025
Emergency Action PlanYes

Identifiers

NID IDCA00214
Federal IDCA00214
More InfoState Dam Safety Program

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