Post Brook Dam
Key Takeaway
Post Brook Dam is classified as high hazard in New Jersey. It was completed in 1923 and is 103 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 | 15 ft (taller than 51.4% in NJ) |
| Dam Length | 316 ft |
| Dam Type | Concrete |
| Normal Storage | 990 acre-ft |
| Surface Area | 73 acres |
| Drainage Area | 4 sq mi |
| Max Discharge | 19 cfs |
| Year Completed | 1923 (103 years old) |
| NID ID | NJ00220 |
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
Lake Iosco
Private
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Low Hazard 7 ftFrequently Asked Questions
What is the hazard classification of Post Brook Dam?
Post Brook 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 Post Brook Dam?
Post Brook Dam is owned by Lake Iosco (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Post Brook Dam built?
Post Brook Dam was completed in 1923, making it 103 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 Post Brook Dam?
Post Brook 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 Post Brook Dam?
Post Brook Dam has a dam height of 15 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 Post Brook Dam last inspected?
Post Brook Dam was last inspected on October 1, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.