Grist Mill Pond Dam
Key Takeaway
Grist Mill Pond Dam is classified as high hazard in New Hampshire. It was completed in 1924 and is 102 years old. Its primary use is hydroelectric. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.
Physical Details
| Dam Height | 16 ft (taller than 54.9% in NH) |
| Dam Length | 135 ft |
| Dam Type | Concrete |
| Max Storage | 175 acre-ft |
| Normal Storage | 125 acre-ft |
| Surface Area | 25 acres |
| Drainage Area | 59 sq mi |
| Max Discharge | 1,755 cfs |
| Year Completed | 1924 (102 years old) |
| Year Modified | 1991 |
| NID ID | NH00060 |
Safety Information
Loss of human life is likely if the dam fails.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
SQUAM RIVER HYDRO LLC
Private
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Significant Hazard 15 ftFrequently Asked Questions
What is the hazard classification of Grist Mill Pond Dam?
Grist Mill Pond Dam is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Grist Mill Pond Dam?
Grist Mill Pond Dam is owned by SQUAM RIVER HYDRO LLC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Grist Mill Pond Dam built?
Grist Mill Pond Dam 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 Grist Mill Pond Dam?
Grist Mill Pond Dam 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 Grist Mill Pond Dam?
Grist Mill Pond Dam has a dam height of 16 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 Grist Mill Pond Dam last inspected?
Grist Mill Pond Dam was last inspected on June 16, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.