Happy Valley Flood Prevention
Key Takeaway
Happy Valley Flood Prevention is classified as high hazard in Hawaii. It was completed in 1980 and is 46 years old. Its primary use is flood risk reduction. 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 | 16 ft (taller than 4.7% in HI) |
| Dam Length | 140 ft |
| Dam Type | Earth |
| Max Storage | 4 acre-ft |
| Normal Storage | 1 acre-ft |
| Surface Area | 0 acres |
| Drainage Area | 0 sq mi |
| Max Discharge | 445 cfs |
| Year Completed | 1980 (46 years old) |
| NID ID | HI00125 |
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
MAUI COUNTY
Local Government
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High Hazard 13 ftFrequently Asked Questions
What is the hazard classification of Happy Valley Flood Prevention?
Happy Valley Flood Prevention 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 Happy Valley Flood Prevention?
Happy Valley Flood Prevention is owned by MAUI COUNTY (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Happy Valley Flood Prevention built?
Happy Valley Flood Prevention was completed in 1980, making it 46 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 Happy Valley Flood Prevention?
Happy Valley Flood Prevention serves the following purposes: Flood Risk Reduction, Debris Control. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Happy Valley Flood Prevention?
Happy Valley Flood Prevention has a dam height of 16 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 Happy Valley Flood Prevention last inspected?
Happy Valley Flood Prevention was last inspected on August 21, 2014. Inspection dates indicate when a formal review occurred, not the results of that inspection.