Northwood Lake Dam
Key Takeaway
Northwood Lake Dam is classified as high hazard in New Hampshire. It was completed in 1926 and is 100 years old. Its primary use is recreation. 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 | 13 ft (taller than 36.5% in NH) |
| Dam Length | 169 ft |
| Dam Type | Concrete |
| Max Storage | 3.2K acre-ft |
| Normal Storage | 2.1K acre-ft |
| Surface Area | 665 acres |
| Drainage Area | 23 sq mi |
| Max Discharge | 1,629 cfs |
| Year Completed | 1926 (100 years old) |
| Year Modified | 1994 |
| NID ID | NH00285 |
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 DES WATER DIVISION
State Government
Nearby Dams
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Low Hazard 7 ftCass Pond Dam
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High Hazard 18 ftHuckins Mill Dam
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Unknown 13 ftPittsfield Sewage Lagoon Dam
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Significant Hazard 18 ftThurston Pond Dam
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Unknown 9 ftAdams Pond Dam
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Low Hazard 10 ftFrequently Asked Questions
What is the hazard classification of Northwood Lake Dam?
Northwood Lake 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 Northwood Lake Dam?
Northwood Lake Dam is owned by NH DES WATER DIVISION (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Northwood Lake Dam built?
Northwood Lake Dam was completed in 1926, making it 100 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 Northwood Lake Dam?
Northwood Lake 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 Northwood Lake Dam?
Northwood Lake Dam has a dam height of 13 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 Northwood Lake Dam last inspected?
Northwood Lake Dam was last inspected on August 31, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.