Lake Cynthia
Key Takeaway
Lake Cynthia is classified as high hazard in California. It was completed in 1955 and is 71 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 | 20 ft (taller than 15.3% in CA) |
| Dam Length | 750 ft |
| Dam Type | Earth |
| Max Storage | 92 acre-ft |
| Surface Area | 12 acres |
| Drainage Area | 1 sq mi |
| Year Completed | 1955 (71 years old) |
| NID ID | CA00980 |
Safety Information
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?
Ownership
Krupp Brothers Vineyard
Private
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High Hazard 40 ftFrequently Asked Questions
What is the hazard classification of Lake Cynthia?
Lake Cynthia 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 Cynthia?
Lake Cynthia is owned by Krupp Brothers Vineyard (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Lake Cynthia built?
Lake Cynthia was completed in 1955, making it 71 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 Cynthia?
Lake Cynthia 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 Cynthia?
Lake Cynthia has a dam height of 20 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 Cynthia last inspected?
Lake Cynthia was last inspected on July 22, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.