Portola
Key Takeaway
Portola is classified as high hazard in California. It was completed in 1980 and is 46 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 | 53 ft (taller than 62.2% in CA) |
| Dam Length | 1,200 ft |
| Dam Type | Earth |
| Max Storage | 586 acre-ft |
| Surface Area | 20 acres |
| Drainage Area | 0 sq mi |
| Year Completed | 1980 (46 years old) |
| NID ID | CA01183 |
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
Santa Margarita Water District
Public Utility
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High Hazard 41 ftFrequently Asked Questions
What is the hazard classification of Portola?
Portola 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 Portola?
Portola is owned by Santa Margarita Water District (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Portola built?
Portola was completed in 1980, making it 46 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 Portola?
Portola 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 Portola?
Portola has a dam height of 53 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 Portola last inspected?
Portola was last inspected on October 26, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.