Rock Island Lake Dam
Key Takeaway
Rock Island Lake Dam is classified as significant hazard in New Jersey. It was completed in 1940 and is 86 years old. Its primary use is recreation. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 19 ft (taller than 70% in NJ) |
| Dam Length | 500 ft |
| Dam Type | Earth |
| Max Storage | 61 acre-ft |
| Normal Storage | 50 acre-ft |
| Surface Area | 11 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 9 cfs |
| Year Completed | 1940 (86 years old) |
| NID ID | NJ00819 |
Safety Information
No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Rock Island Lake Owners Assoc.
Private
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High Hazard 26 ftFrequently Asked Questions
What is the hazard classification of Rock Island Lake Dam?
Rock Island Lake Dam is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Rock Island Lake Dam?
Rock Island Lake Dam is owned by Rock Island Lake Owners Assoc. (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Rock Island Lake Dam built?
Rock Island Lake Dam was completed in 1940, making it 86 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 Rock Island Lake Dam?
Rock Island 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 Rock Island Lake Dam?
Rock Island Lake Dam has a dam height of 19 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 Rock Island Lake Dam last inspected?
Rock Island Lake Dam was last inspected on November 6, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.