Otis Falls
Key Takeaway
Otis Falls is classified as significant hazard in New Hampshire. It was completed in 1982 and is 44 years old. Its primary use is hydroelectric. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 27 ft (taller than 83.7% in NH) |
| Dam Length | 150 ft |
| Dam Type | Concrete |
| Max Storage | 64 acre-ft |
| Normal Storage | 64 acre-ft |
| Surface Area | 7 acres |
| Drainage Area | 30 sq mi |
| Max Discharge | 3,327 cfs |
| Year Completed | 1982 (44 years old) |
| NID ID | NH00041 |
Safety Information
No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Alden Hydro, LLC
Private
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Low Hazard 9 ftFrequently Asked Questions
What is the hazard classification of Otis Falls?
Otis Falls is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Otis Falls?
Otis Falls is owned by Alden Hydro, LLC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Otis Falls built?
Otis Falls was completed in 1982, making it 44 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 Otis Falls?
Otis Falls serves the following purposes: Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Otis Falls?
Otis Falls has a dam height of 27 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 Otis Falls last inspected?
Otis Falls was last inspected on September 30, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.