Whittier Reservoir No. 4

Tr San Gabriel Riv· Los Angeles, California· Built 1931· Earth· 55 ft tall
Low Hazard Water Supply Local Government

Key Takeaway

Whittier Reservoir No. 4 is classified as low hazard in California. It was completed in 1931 and is 95 years old. Its primary use is water supply.

Physical Details

Dam Height 55 ft (taller than 63.8% in CA)
Dam Length190 ft
Dam TypeEarth
Max Storage32 acre-ft
Surface Area1 acres
Drainage Area0 sq mi
Year Completed1931 (95 years old)
NID IDCA00153

Safety Information

Low Hazard

No probable loss of human life and low economic/environmental losses expected.

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

Emergency Action Plan: No
Last Inspection: February 16, 2022
State Regulated: Yes
Regulatory Agency: DWR, Division of Safety of Dams

Ownership

City of Whittier Water District

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Whittier Reservoir No. 4?

Whittier Reservoir No. 4 is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Whittier Reservoir No. 4?

Whittier Reservoir No. 4 is owned by City of Whittier Water District (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Whittier Reservoir No. 4 built?

Whittier Reservoir No. 4 was completed in 1931, making it 95 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 Reservoir No. 4?

Whittier Reservoir No. 4 serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Whittier Reservoir No. 4?

Whittier Reservoir No. 4 has a dam height of 55 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 Reservoir No. 4 last inspected?

Whittier Reservoir No. 4 was last inspected on February 16, 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.