Back Lake Dam
Key Takeaway
Back Lake Dam is classified as low hazard in New Hampshire. It was completed in 1930 and is 96 years old. Its primary use is recreation.
Physical Details
| Dam Height | 7 ft (taller than 1.4% in NH) |
| Dam Length | 36 ft |
| Dam Type | Concrete |
| Max Storage | 1.3K acre-ft |
| Normal Storage | 574 acre-ft |
| Surface Area | 348 acres |
| Drainage Area | 2 sq mi |
| Max Discharge | 207 cfs |
| Year Completed | 1930 (96 years old) |
| Year Modified | 1955 |
| NID ID | NH00584 |
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
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Low Hazard 25 ftFrequently Asked Questions
What is the hazard classification of Back Lake Dam?
Back Lake 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 Back Lake Dam?
Back Lake 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 Back Lake Dam built?
Back Lake Dam was completed in 1930, making it 96 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 Back Lake Dam?
Back 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 Back Lake Dam?
Back Lake Dam has a dam height of 7 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 Back Lake Dam last inspected?
Back Lake Dam was last inspected on June 16, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.