Lake Jefferson
Key Takeaway
Lake Jefferson is classified as high hazard in New York. It was completed in 1927 and is 99 years old. Its primary use is hydroelectric. 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 | 22 ft (taller than 63.7% in NY) |
| Dam Length | 220 ft |
| Dam Type | Gravity |
| Max Storage | 350 acre-ft |
| Normal Storage | 350 acre-ft |
| Surface Area | 30 acres |
| Drainage Area | 30 sq mi |
| Max Discharge | 6,865 cfs |
| Year Completed | 1927 (99 years old) |
| NID ID | NY00205 |
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
Barbara A. & Kevin J. Gref
Private
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What is the hazard classification of Lake Jefferson?
Lake Jefferson 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 Lake Jefferson?
Lake Jefferson is owned by Barbara A. & Kevin J. Gref (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Lake Jefferson built?
Lake Jefferson was completed in 1927, making it 99 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 Lake Jefferson?
Lake Jefferson 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 Lake Jefferson?
Lake Jefferson has a dam height of 22 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 Lake Jefferson last inspected?
Lake Jefferson was last inspected on May 12, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.