Circle S
Key Takeaway
Circle S is classified as high hazard in California. It was completed in 1979 and is 47 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 | 28 ft (taller than 27.2% in CA) |
| Dam Length | 412 ft |
| Dam Type | Earth |
| Max Storage | 131 acre-ft |
| Surface Area | 9 acres |
| Drainage Area | 1 sq mi |
| Year Completed | 1979 (47 years old) |
| NID ID | CA01141 |
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
Circle S. Ranch, LLC
Private
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Significant Hazard 36 ftFrequently Asked Questions
What is the hazard classification of Circle S?
Circle S 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 Circle S?
Circle S is owned by Circle S. Ranch, LLC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Circle S built?
Circle S was completed in 1979, making it 47 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 Circle S?
Circle S 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 Circle S?
Circle S has a dam height of 28 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 Circle S last inspected?
Circle S was last inspected on March 16, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.