Blackwater Dam - Dodge Estate Dike
Key Takeaway
Blackwater Dam - Dodge Estate Dike is classified as high hazard in New Hampshire. It was completed in 1941 and is 85 years old. Its primary use is flood risk reduction. 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 | 18 ft (taller than 63.5% in NH) |
| Dam Length | 400 ft |
| Dam Type | Gravity |
| Max Storage | 93.4K acre-ft |
| Normal Storage | 0 acre-ft |
| Surface Area | 1 acres |
| Drainage Area | 128 sq mi |
| Max Discharge | 42,800 cfs |
| Year Completed | 1941 (85 years old) |
| NID ID | NH03847 |
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
USACE - New England District
Federal Government
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Low Hazard 10 ftFrequently Asked Questions
What is the hazard classification of Blackwater Dam - Dodge Estate Dike?
Blackwater Dam - Dodge Estate Dike 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 Blackwater Dam - Dodge Estate Dike?
Blackwater Dam - Dodge Estate Dike is owned by USACE - New England District (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Blackwater Dam - Dodge Estate Dike built?
Blackwater Dam - Dodge Estate Dike was completed in 1941, making it 85 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 Blackwater Dam - Dodge Estate Dike?
Blackwater Dam - Dodge Estate Dike serves the following purposes: Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Blackwater Dam - Dodge Estate Dike?
Blackwater Dam - Dodge Estate Dike has a dam height of 18 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 Blackwater Dam - Dodge Estate Dike last inspected?
Blackwater Dam - Dodge Estate Dike was last inspected on October 25, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.