Lyons
Key Takeaway
Lyons is classified as high hazard in California. It was completed in 1930 and is 96 years old. Its primary use is hydroelectric. 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 | 132 ft (taller than 87.4% in CA) |
| Dam Length | 535 ft |
| Dam Type | Concrete |
| Max Storage | 6.2K acre-ft |
| Normal Storage | 6.2K acre-ft |
| Surface Area | 184 acres |
| Drainage Area | 67 sq mi |
| Max Discharge | 21,000 cfs |
| Year Completed | 1930 (96 years old) |
| NID ID | CA00387 |
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
Pacific Gas and Electric Company
Private
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Significant Hazard 242 ftFrequently Asked Questions
What is the hazard classification of Lyons?
Lyons 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 Lyons?
Lyons is owned by Pacific Gas and Electric Company (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Lyons built?
Lyons was completed in 1930, making it 96 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 Lyons?
Lyons serves the following purposes: Hydroelectric, Fire Protection, Stock, Or Small Fish Pond, Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Lyons?
Lyons has a dam height of 132 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 Lyons last inspected?
Lyons was last inspected on July 8, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.