Allen
Key Takeaway
Allen 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 | 33 ft (taller than 35.9% in CA) |
| Dam Length | 250 ft |
| Dam Type | Earth |
| Max Storage | 85 acre-ft |
| Surface Area | 11 acres |
| Drainage Area | 1 sq mi |
| Year Completed | 1955 (71 years old) |
| NID ID | CA00569 |
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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Significant Hazard 13 ftFrequently Asked Questions
What is the hazard classification of Allen?
Allen 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 Allen?
Allen is owned by Private Entity (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Allen built?
Allen 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 Allen?
Allen 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 Allen?
Allen has a dam height of 33 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 Allen last inspected?
Allen was last inspected on February 17, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.