Lake Orinda

Cascade Creek· Contra Costa, California· Built 1935· Earth· 45 ft tall
High Hazard Water Supply Irrigation Private

Key Takeaway

Lake Orinda is classified as high hazard in California. It was completed in 1935 and is 91 years old. Its primary use is water supply. 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 45 ft (taller than 54% in CA)
Dam Length360 ft
Dam TypeEarth
Max Storage111 acre-ft
Surface Area10 acres
Drainage Area1 sq mi
Max Discharge474 cfs
Year Completed1935 (91 years old)
NID IDCA00659

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: January 28, 2022
State Regulated: Yes
Regulatory Agency: DWR, Division of Safety of Dams

Ownership

Orinda Country Club

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Lake Orinda?

Lake Orinda 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 Lake Orinda?

Lake Orinda is owned by Orinda Country Club (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Lake Orinda built?

Lake Orinda was completed in 1935, making it 91 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 Lake Orinda?

Lake Orinda serves the following purposes: Water Supply, Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Lake Orinda?

Lake Orinda has a dam height of 45 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 Lake Orinda last inspected?

Lake Orinda was last inspected on January 28, 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.