Pyramid

Pyramid is an earth dam located in Los Angeles County, California, built in 1974. It carries a High hazard potential classification and has a fair condition assessment.

About Pyramid

The primary purpose of Pyramid 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 California Department Of Water Resources (state). It impounds the Piru Creek near Piru.

The dam stands 422 feet tall and stretches 1,090 feet across, creates a reservoir covering 1,290 acres, has a maximum storage capacity of 171,000 acre-feet, and collects water from a drainage area of 432 square miles. Completed in 1974, the structure is well into its service life at over 50 years old.

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 fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 05/06/2025.

At 422 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 HazardFair ConditionEmergency Action Plan: Yes

Location

StateCalifornia
CountyLos Angeles
Nearest CityPiru
River/StreamPiru Creek
Coordinates34.64430, -118.76450

Physical Characteristics

Dam TypeEarth
NID Height422 ft
Dam Height400 ft
Dam Length1,090 ft
Year Completed1974 (52 years old)

Storage & Hydraulics

NID Storage171,000 acre-ft
Max Storage171,000 acre-ft
Normal Storage170,000 acre-ft
Surface Area1,290 acres
Drainage Area432 sq mi
Max Discharge20,000 cfs
Spillway TypeControlled

Ownership & Safety

PurposeWater Supply
OwnerCalifornia Department of Water Resources
Owner TypeState
Hazard ClassificationHigh
Condition AssessmentFair
Last Inspection05/06/2025
Emergency Action PlanYes

Identifiers

NID IDCA00052
Federal IDCA00052
More InfoState Dam Safety Program

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