Loon Lake Dam
Key Takeaway
Loon Lake Dam is classified as high hazard in New Hampshire. It was completed in 1920 and is 106 years old. Its primary use is recreation. 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 | 15 ft (taller than 47.8% in NH) |
| Dam Length | 100 ft |
| Dam Type | Concrete |
| Max Storage | 458 acre-ft |
| Normal Storage | 199 acre-ft |
| Surface Area | 54 acres |
| Drainage Area | 7 sq mi |
| Year Completed | 1920 (106 years old) |
| Year Modified | 1961 |
| NID ID | NH00605 |
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
FRIENDS OF LOON LAKE LLC
Private
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Significant Hazard 15 ftFrequently Asked Questions
What is the hazard classification of Loon Lake Dam?
Loon Lake Dam 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 Loon Lake Dam?
Loon Lake Dam is owned by FRIENDS OF LOON LAKE LLC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Loon Lake Dam built?
Loon Lake Dam was completed in 1920, making it 106 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 Loon Lake Dam?
Loon Lake Dam serves the following purposes: Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Loon Lake Dam?
Loon Lake Dam has a dam height of 15 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 Loon Lake Dam last inspected?
Loon Lake Dam was last inspected on October 7, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.