Emerald Lake 1 Lower
Key Takeaway
Emerald Lake 1 Lower is classified as high hazard in California. It was completed in 1885 and is 141 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 | 57 ft (taller than 65.7% in CA) |
| Dam Length | 280 ft |
| Dam Type | Earth |
| Max Storage | 45 acre-ft |
| Surface Area | 4 acres |
| Drainage Area | 0 sq mi |
| Year Completed | 1885 (141 years old) |
| NID ID | CA00668 |
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
Emerald Lake Country Club
Private
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High Hazard 67 ftFrequently Asked Questions
What is the hazard classification of Emerald Lake 1 Lower?
Emerald Lake 1 Lower 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 Emerald Lake 1 Lower?
Emerald Lake 1 Lower is owned by Emerald Lake Country Club (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Emerald Lake 1 Lower built?
Emerald Lake 1 Lower was completed in 1885, making it 141 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 Emerald Lake 1 Lower?
Emerald Lake 1 Lower serves the following purposes: Water Supply, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Emerald Lake 1 Lower?
Emerald Lake 1 Lower has a dam height of 57 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 Emerald Lake 1 Lower last inspected?
Emerald Lake 1 Lower was last inspected on June 23, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.