Ammonoosuc River
Key Takeaway
Ammonoosuc River is classified as low hazard in New Hampshire. It was completed in 1900 and is 126 years old. Its primary use is hydroelectric.
Physical Details
| Dam Height | 17 ft (taller than 59.6% in NH) |
| Dam Length | 365 ft |
| Dam Type | Concrete |
| Max Storage | 352 acre-ft |
| Normal Storage | 280 acre-ft |
| Surface Area | 24 acres |
| Drainage Area | 395 sq mi |
| Max Discharge | 40,000 cfs |
| Year Completed | 1900 (126 years old) |
| NID ID | NH00061 |
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
Bath Electric Power Company LLC
Private
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Low Hazard 18 ftFrequently Asked Questions
What is the hazard classification of Ammonoosuc River?
Ammonoosuc River 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 Ammonoosuc River?
Ammonoosuc River is owned by Bath Electric Power Company LLC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Ammonoosuc River built?
Ammonoosuc River was completed in 1900, making it 126 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 Ammonoosuc River?
Ammonoosuc River 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 Ammonoosuc River?
Ammonoosuc River has a dam height of 17 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 Ammonoosuc River last inspected?
Ammonoosuc River was last inspected on August 17, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.