Powder Mill
Key Takeaway
Powder Mill is classified as low hazard in New Hampshire. It was completed in 1924 and is 102 years old. Its primary use is hydroelectric.
Physical Details
| Dam Height | 21 ft (taller than 74.5% in NH) |
| Dam Length | 366 ft |
| Dam Type | Concrete |
| Max Storage | 8.6K acre-ft |
| Normal Storage | 2.4K acre-ft |
| Surface Area | 435 acres |
| Drainage Area | 184 sq mi |
| Max Discharge | 18,200 cfs |
| Year Completed | 1924 (102 years old) |
| NID ID | NH00248 |
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 Powder Mill?
Powder Mill 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 Powder Mill?
Powder Mill is owned by Monadnock Paper Mills, Inc. (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Powder Mill built?
Powder Mill 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 Powder Mill?
Powder Mill 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 Powder Mill?
Powder Mill has a dam height of 21 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 Powder Mill last inspected?
Powder Mill was last inspected on June 15, 2017. Inspection dates indicate when a formal review occurred, not the results of that inspection.