J. Seward Johnson Dam
Key Takeaway
J. Seward Johnson Dam is classified as low hazard in New Jersey. It was completed in 1967 and is 59 years old. Its primary use is irrigation.
Physical Details
| Dam Height | 24 ft (taller than 83.4% in NJ) |
| Dam Length | 1,150 ft |
| Dam Type | Earth |
| Normal Storage | 50 acre-ft |
| Surface Area | 6 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 450 cfs |
| Year Completed | 1967 (59 years old) |
| NID ID | NJ00770 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
James Loring Johnson
Private
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Significant Hazard 30 ftFrequently Asked Questions
What is the hazard classification of J. Seward Johnson Dam?
J. Seward Johnson Dam is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates J. Seward Johnson Dam?
J. Seward Johnson Dam is owned by James Loring Johnson (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was J. Seward Johnson Dam built?
J. Seward Johnson Dam was completed in 1967, making it 59 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 J. Seward Johnson Dam?
J. Seward Johnson Dam serves the following purposes: Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is J. Seward Johnson Dam?
J. Seward Johnson Dam has a dam height of 24 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 J. Seward Johnson Dam last inspected?
J. Seward Johnson Dam was last inspected on March 11, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.