China Mill Dam
Key Takeaway
China Mill Dam is classified as high hazard in New Hampshire. It was completed in 1860 and is 166 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 | 29 ft (taller than 86% in NH) |
| Dam Length | 275 ft |
| Dam Type | Concrete |
| Max Storage | 33 acre-ft |
| Normal Storage | 22 acre-ft |
| Surface Area | 2 acres |
| Drainage Area | 259 sq mi |
| Max Discharge | 16,770 cfs |
| Year Completed | 1860 (166 years old) |
| Year Modified | 2004 |
| NID ID | NH00023 |
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
NH HYDRO ASSOC
Private
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Significant Hazard 8 ftFrequently Asked Questions
What is the hazard classification of China Mill Dam?
China Mill 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 China Mill Dam?
China Mill Dam is owned by NH HYDRO ASSOC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was China Mill Dam built?
China Mill Dam was completed in 1860, making it 166 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 China Mill Dam?
China Mill 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 China Mill Dam?
China Mill Dam has a dam height of 29 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 China Mill Dam last inspected?
China Mill Dam was last inspected on November 4, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.