Upper 4s Ranch
Key Takeaway
Upper 4s Ranch is classified as low hazard in California. It was completed in 1927 and is 99 years old. Its primary use is water supply.
Physical Details
| Dam Height | 28 ft (taller than 27.2% in CA) |
| Dam Length | 246 ft |
| Dam Type | Arch |
| Max Storage | 48 acre-ft |
| Surface Area | 10 acres |
| Drainage Area | 2 sq mi |
| Year Completed | 1927 (99 years old) |
| NID ID | CA00779 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
4S Ranch Master Association
Private
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High Hazard 165 ftFrequently Asked Questions
What is the hazard classification of Upper 4s Ranch?
Upper 4s Ranch is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Upper 4s Ranch?
Upper 4s Ranch is owned by 4S Ranch Master Association (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Upper 4s Ranch built?
Upper 4s Ranch was completed in 1927, making it 99 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 Upper 4s Ranch?
Upper 4s Ranch 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 Upper 4s Ranch?
Upper 4s Ranch 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 Upper 4s Ranch last inspected?
Upper 4s Ranch was last inspected on March 24, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.