Hanakaoo Reservoir
Key Takeaway
Hanakaoo Reservoir is classified as high hazard in Hawaii. It was completed in 1918 and is 108 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 | 27 ft (taller than 29.9% in HI) |
| Dam Length | 740 ft |
| Dam Type | Earth |
| Max Storage | 30 acre-ft |
| Normal Storage | 25 acre-ft |
| Surface Area | 2 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 7 cfs |
| Year Completed | 1918 (108 years old) |
| NID ID | HI00056 |
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
Kaanapali Land Management Corp.
Private
Nearby Dams
Horner Reservoir
Maui, HI
High Hazard 70 ftReservoir 140
Maui, HI
High Hazard 35 ftMahinahina Reservoir
Maui, HI
High Hazard 34 ftUpper Field 14 Reservoir
Maui, HI
High Hazard 38 ftMiddle Field 14 Reservoir
Maui, HI
High Hazard 36 ftKahoma Reservoir
Maui, HI
High Hazard 60 ftHonokowai Reservoir
Maui, HI
High Hazard 31 ftHonokowai - Structure #8
Maui, HI
High Hazard 41 ftFrequently Asked Questions
What is the hazard classification of Hanakaoo Reservoir?
Hanakaoo 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 Hanakaoo Reservoir?
Hanakaoo Reservoir is owned by Kaanapali Land Management Corp. (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Hanakaoo Reservoir built?
Hanakaoo Reservoir was completed in 1918, making it 108 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 Hanakaoo Reservoir?
Hanakaoo 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 Hanakaoo Reservoir?
Hanakaoo Reservoir has a dam height of 27 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 Hanakaoo Reservoir last inspected?
Hanakaoo Reservoir was last inspected on July 22, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.