Grassy Pond Dam
Key Takeaway
Grassy Pond Dam is classified as low hazard in New Hampshire. It was completed in 1836 and is 190 years old. Its primary use is recreation.
Physical Details
| Dam Height | 9 ft (taller than 10.9% in NH) |
| Dam Length | 75 ft |
| Dam Type | Concrete |
| Max Storage | 204 acre-ft |
| Normal Storage | 79 acre-ft |
| Surface Area | 35 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 565 cfs |
| Year Completed | 1836 (190 years old) |
| Year Modified | 1951 |
| NID ID | NH00418 |
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
NH FISH AND GAME DEPARTMENT
State Government
Nearby Dams
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Significant Hazard 14 ftHopkinton Dam
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High Hazard 71 ftHopkinton Dam - Dike H-2
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High Hazard 77 ftHopkinton Sewage Lagoon Dam
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Significant Hazard 18 ftHopkinton
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Low Hazard 10 ftHopkinton Dam - Dike H-3
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High Hazard 66 ftWinnipocket Lake Dam
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Low Hazard 7 ftFrequently Asked Questions
What is the hazard classification of Grassy Pond Dam?
Grassy Pond Dam 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 Grassy Pond Dam?
Grassy Pond Dam is owned by NH FISH AND GAME DEPARTMENT (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Grassy Pond Dam built?
Grassy Pond Dam was completed in 1836, making it 190 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 Grassy Pond Dam?
Grassy Pond Dam serves the following purposes: Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Grassy Pond Dam?
Grassy Pond Dam has a dam height of 9 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 Grassy Pond Dam last inspected?
Grassy Pond Dam was last inspected on March 31, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.