Second Connecticut Lake Dam
Key Takeaway
Second Connecticut Lake Dam is classified as low hazard in New Hampshire. It was completed in 1849 and is 177 years old. Its primary use is hydroelectric.
Physical Details
| Dam Height | 28 ft (taller than 84.8% in NH) |
| Dam Length | 568 ft |
| Dam Type | Earth |
| Max Storage | 12.5K acre-ft |
| Normal Storage | 11.7K acre-ft |
| Surface Area | 1,300 acres |
| Drainage Area | 45 sq mi |
| Max Discharge | 11,000 cfs |
| Year Completed | 1849 (177 years old) |
| Year Modified | 1934 |
| NID ID | NH00187 |
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
GREAT RIVER HYDRO LLC
Private
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High Hazard 56 ftFrequently Asked Questions
What is the hazard classification of Second Connecticut Lake Dam?
Second Connecticut 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 Second Connecticut Lake Dam?
Second Connecticut Lake Dam is owned by GREAT RIVER HYDRO LLC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Second Connecticut Lake Dam built?
Second Connecticut Lake Dam was completed in 1849, making it 177 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 Second Connecticut Lake Dam?
Second Connecticut Lake 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 Second Connecticut Lake Dam?
Second Connecticut Lake Dam has a dam height of 28 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 Second Connecticut Lake Dam last inspected?
Second Connecticut Lake Dam was last inspected on June 24, 2019. Inspection dates indicate when a formal review occurred, not the results of that inspection.