Mirror Lake Dam
Key Takeaway
Mirror Lake Dam is classified as low hazard in New Hampshire. It was completed in 1836 and is 190 years old. Its primary use is recreation.
Physical Details
| Dam Height | 12 ft (taller than 28.2% in NH) |
| Dam Length | 290 ft |
| Dam Type | Earth |
| Max Storage | 187 acre-ft |
| Normal Storage | 136 acre-ft |
| Surface Area | 38 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 215 cfs |
| Year Completed | 1836 (190 years old) |
| Year Modified | 1964 |
| NID ID | NH00317 |
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 DES WATER DIVISION
State Government
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Low Hazard 8 ftFrequently Asked Questions
What is the hazard classification of Mirror Lake Dam?
Mirror 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 Mirror Lake Dam?
Mirror 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 Mirror Lake Dam built?
Mirror Lake Dam was completed in 1836, making it 190 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 Mirror Lake Dam?
Mirror 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 Mirror Lake Dam?
Mirror Lake Dam has a dam height of 12 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 Mirror Lake Dam last inspected?
Mirror Lake Dam was last inspected on September 20, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.