Okinawa Reservoir
Key Takeaway
Okinawa Reservoir is classified as high hazard in Hawaii. It was completed in 1920 and is 106 years old. Its primary use is irrigation. 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 | 25 ft (taller than 21.3% in HI) |
| Dam Length | 470 ft |
| Dam Type | Earth |
| Max Storage | 142 acre-ft |
| Normal Storage | 84 acre-ft |
| Surface Area | 14 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 1,000 cfs |
| Year Completed | 1920 (106 years old) |
| NID ID | HI00014 |
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
Grove Farm Company
Private
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High Hazard 20 ftFrequently Asked Questions
What is the hazard classification of Okinawa Reservoir?
Okinawa Reservoir 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 Okinawa Reservoir?
Okinawa Reservoir is owned by Grove Farm Company (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Okinawa Reservoir built?
Okinawa Reservoir was completed in 1920, making it 106 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 Okinawa Reservoir?
Okinawa Reservoir 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 Okinawa Reservoir?
Okinawa Reservoir has a dam height of 25 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 Okinawa Reservoir last inspected?
Okinawa Reservoir was last inspected on June 30, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.