Monadnock
Key Takeaway
Monadnock is classified as low hazard in New Hampshire. It was completed in 1923 and is 103 years old. Its primary use is hydroelectric.
Physical Details
| Dam Height | 22 ft (taller than 76.5% in NH) |
| Dam Length | 500 ft |
| Dam Type | Concrete |
| Max Storage | 240 acre-ft |
| Normal Storage | 217 acre-ft |
| Surface Area | 4 acres |
| Drainage Area | 190 sq mi |
| Max Discharge | 13,400 cfs |
| Year Completed | 1923 (103 years old) |
| NID ID | NH00249 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Monadnock Paper Mills, Inc.
Private
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Low Hazard 9 ftFrequently Asked Questions
What is the hazard classification of Monadnock?
Monadnock is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Monadnock?
Monadnock is owned by Monadnock Paper Mills, Inc. (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Monadnock built?
Monadnock was completed in 1923, making it 103 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 Monadnock?
Monadnock serves the following purposes: Hydroelectric, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Monadnock?
Monadnock has a dam height of 22 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 Monadnock last inspected?
Monadnock was last inspected on June 15, 2017. Inspection dates indicate when a formal review occurred, not the results of that inspection.