Whittier Narrows Dam

SAN GABRIEL RIVER· Los Angeles, California· Built 1957· Earth· 56 ft tall
High Hazard Flood Risk Reduction Recreation Water Supply Federal Government

Key Takeaway

Whittier Narrows Dam is classified as high hazard in California. It was completed in 1957 and is 69 years old. Its primary use is flood risk reduction. 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 56 ft (taller than 65.1% in CA)
Dam Length16,960 ft
Dam TypeEarth
Max Storage66.7K acre-ft
Normal Storage0 acre-ft
Surface Area1 acres
Drainage Area554 sq mi
Max Discharge307,900 cfs
Year Completed1957 (69 years old)
NID IDCA10027

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: July 7, 2022
State Regulated: No

Ownership

USACE - Los Angeles District

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Whittier Narrows Dam?

Whittier Narrows Dam 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 Whittier Narrows Dam?

Whittier Narrows Dam is owned by USACE - Los Angeles District (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Whittier Narrows Dam built?

Whittier Narrows Dam was completed in 1957, making it 69 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 Whittier Narrows Dam?

Whittier Narrows Dam serves the following purposes: Flood Risk Reduction, Recreation, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Whittier Narrows Dam?

Whittier Narrows Dam has a dam height of 56 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 Whittier Narrows Dam last inspected?

Whittier Narrows Dam was last inspected on July 7, 2022. 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.