Lake Helen
Key Takeaway
Lake Helen is classified as high hazard in California. It was completed in 1966 and is 60 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 | 39 ft (taller than 44.4% in CA) |
| Dam Length | 355 ft |
| Dam Type | Earth |
| Max Storage | 192 acre-ft |
| Surface Area | 14 acres |
| Drainage Area | 0 sq mi |
| Year Completed | 1966 (60 years old) |
| NID ID | CA01060 |
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
Private Entity
Private
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Low Hazard 12 ftFrequently Asked Questions
What is the hazard classification of Lake Helen?
Lake Helen 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 Helen?
Lake Helen is owned by Private Entity (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Lake Helen built?
Lake Helen was completed in 1966, making it 60 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 Helen?
Lake Helen serves the following purposes: Water Supply, Irrigation, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Lake Helen?
Lake Helen has a dam height of 39 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 Helen last inspected?
Lake Helen was last inspected on August 19, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.