Irish Brook Dam
Key Takeaway
Irish 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 | 17 ft (taller than 63.3% in NJ) |
| Dam Length | 259 ft |
| Dam Type | Concrete |
| Normal Storage | 990 acre-ft |
| Surface Area | 73 acres |
| Drainage Area | 4 sq mi |
| Max Discharge | 21 cfs |
| Year Completed | 1923 (103 years old) |
| NID ID | NJ00204 |
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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What is the hazard classification of Irish Brook Dam?
Irish 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 Irish Brook Dam?
Irish Brook Dam is owned by Lake Iosco (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Irish Brook Dam built?
Irish 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 Irish Brook Dam?
Irish 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 Irish Brook Dam?
Irish Brook Dam has a dam height of 17 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 Irish Brook Dam last inspected?
Irish Brook Dam was last inspected on October 1, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.