Upper Greenwood Lake Dam
Key Takeaway
Upper Greenwood Lake Dam is classified as high hazard in New Jersey. It was completed in 1932 and is 94 years old. Its primary use is recreation. 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 | 20 ft (taller than 72.4% in NJ) |
| Dam Length | 460 ft |
| Dam Type | Earth |
| Max Storage | 5.0K acre-ft |
| Normal Storage | 2.1K acre-ft |
| Surface Area | 385 acres |
| Drainage Area | 5 sq mi |
| Max Discharge | 2,700 cfs |
| Year Completed | 1932 (94 years old) |
| NID ID | NJ00186 |
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
Upper Greenwood Lake Property Owners Association
Private
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High Hazard 15 ftFrequently Asked Questions
What is the hazard classification of Upper Greenwood Lake Dam?
Upper Greenwood Lake 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 Upper Greenwood Lake Dam?
Upper Greenwood Lake Dam is owned by Upper Greenwood Lake Property Owners Association (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Upper Greenwood Lake Dam built?
Upper Greenwood Lake Dam was completed in 1932, making it 94 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 Upper Greenwood Lake Dam?
Upper Greenwood 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 Upper Greenwood Lake Dam?
Upper Greenwood Lake Dam has a dam height of 20 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 Upper Greenwood Lake Dam last inspected?
Upper Greenwood Lake Dam was last inspected on June 4, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.