San Gabriel

San Gabriel River· Los Angeles, California· Built 1937· Earth· 320 ft tall
High Hazard Hydroelectric Flood Risk Reduction Local Government

Key Takeaway

San Gabriel is classified as high hazard in California. It was completed in 1937 and is 89 years old. Its primary use is hydroelectric. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.

Physical Details

Dam Height 320 ft (taller than 98.8% in CA)
Dam Length1,500 ft
Dam TypeEarth
Max Storage45.8K acre-ft
Normal Storage3.4K acre-ft
Drainage Area203 sq mi
Max Discharge297,000 cfs
Year Completed1937 (89 years old)
NID IDCA00200

Safety Information

High Hazard

Loss of human life is likely if the dam fails.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: Yes
Last Inspection: September 12, 2023
State Regulated: Yes
Regulatory Agency: DWR, Safety of Dams

Ownership

Los Angeles County Flood Control District

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of San Gabriel?

San Gabriel is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates San Gabriel?

San Gabriel is owned by Los Angeles County Flood Control District (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was San Gabriel built?

San Gabriel was completed in 1937, making it 89 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.

What is the primary purpose of San Gabriel?

San Gabriel serves the following purposes: Hydroelectric, Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is San Gabriel?

San Gabriel has a dam height of 320 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.

When was San Gabriel last inspected?

San Gabriel was last inspected on September 12, 2023. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.