Blanchard-Offner
Key Takeaway
Blanchard-Offner is classified as high hazard in California. It was completed in 1963 and is 63 years old. Its primary use is other. 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 | 47 ft (taller than 56.2% in CA) |
| Dam Length | 785 ft |
| Dam Type | Earth |
| Max Storage | 274 acre-ft |
| Surface Area | 19 acres |
| Year Completed | 1963 (63 years old) |
| NID ID | CA01037 |
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 40 ftFrequently Asked Questions
What is the hazard classification of Blanchard-Offner?
Blanchard-Offner 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 Blanchard-Offner?
Blanchard-Offner is owned by Private Entity (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Blanchard-Offner built?
Blanchard-Offner was completed in 1963, making it 63 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 Blanchard-Offner?
Blanchard-Offner serves the following purposes: Other, Irrigation, Recreation, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Blanchard-Offner?
Blanchard-Offner has a dam height of 47 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 Blanchard-Offner last inspected?
Blanchard-Offner was last inspected on August 18, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.