Ayers Island
Key Takeaway
Ayers Island is classified as significant hazard in New Hampshire. It was completed in 1924 and is 102 years old. Its primary use is hydroelectric. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 80 ft (taller than 98.6% in NH) |
| Dam Length | 699 ft |
| Dam Type | Concrete |
| Max Storage | 10.0K acre-ft |
| Normal Storage | 10.0K acre-ft |
| Surface Area | 800 acres |
| Drainage Area | 746 sq mi |
| Max Discharge | 92,100 cfs |
| Year Completed | 1924 (102 years old) |
| NID ID | NH00160 |
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
Not Listed
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Significant Hazard 15 ftFrequently Asked Questions
What is the hazard classification of Ayers Island?
Ayers Island 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 Ayers Island?
Ayers Island is owned by information not available (Not Listed). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Ayers Island built?
Ayers Island was completed in 1924, making it 102 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 Ayers Island?
Ayers Island 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 Ayers Island?
Ayers Island has a dam height of 80 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 Ayers Island last inspected?
Ayers Island was last inspected on July 26, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.