San Gabriel

San Gabriel is an earth dam located in Los Angeles County, California, built in 1937. It carries a High hazard potential classification and has a satisfactory condition assessment.

About San Gabriel

The primary purpose of San Gabriel is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by Los Angeles County Flood Control District (local government). It impounds the San Gabriel River near Azusa.

The dam stands 381 feet tall and stretches 1,500 feet across, has a maximum storage capacity of 45,832 acre-feet, and collects water from a drainage area of 203 square miles. Completed in 1937, 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 09/12/2023.

At 381 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
CountyLos Angeles
Nearest CityAzusa
River/StreamSan Gabriel River
Coordinates34.20650, -117.85920

Physical Characteristics

Dam TypeEarth
NID Height381 ft
Dam Height320 ft
Dam Length1,500 ft
Year Completed1937 (89 years old)

Storage & Hydraulics

NID Storage45,832 acre-ft
Max Storage45,832 acre-ft
Normal Storage3,378 acre-ft
Drainage Area203 sq mi
Max Discharge297,000 cfs
Spillway TypeUncontrolled

Ownership & Safety

PurposeHydroelectric
OwnerLos Angeles County Flood Control District
Owner TypeLocal Government
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection09/12/2023
Emergency Action PlanYes

Identifiers

NID IDCA00200
Federal IDCA00200
More InfoState Dam Safety Program

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