Lake Deforest Dam
Key Takeaway
Lake Deforest Dam is classified as high hazard in New York. It was completed in 1956 and is 70 years old. Its primary use is water supply. 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 | 40 ft (taller than 88.1% in NY) |
| Dam Length | 1,330 ft |
| Dam Type | Earth |
| Max Storage | 36.4K acre-ft |
| Normal Storage | 17.3K acre-ft |
| Surface Area | 900 acres |
| Drainage Area | 27 sq mi |
| Year Completed | 1956 (70 years old) |
| NID ID | NY00095 |
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
SUEZ WATER NEW YORK
Public Utility
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Significant Hazard 26 ftFrequently Asked Questions
What is the hazard classification of Lake Deforest Dam?
Lake Deforest 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 Lake Deforest Dam?
Lake Deforest Dam is owned by SUEZ WATER NEW YORK (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Lake Deforest Dam built?
Lake Deforest Dam was completed in 1956, making it 70 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 Deforest Dam?
Lake Deforest Dam serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Lake Deforest Dam?
Lake Deforest Dam has a dam height of 40 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 Deforest Dam last inspected?
Lake Deforest Dam was last inspected on November 23, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.