Wailua Reservoir

WAILUA RIVER-N. FORK OFFSTREAM· Kauai, Hawaii· Built 1920· Earth· 40 ft tall
High Hazard Irrigation State Government

Key Takeaway

Wailua 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 40 ft (taller than 65.4% in HI)
Dam Length1,080 ft
Dam TypeEarth
Max Storage1.2K acre-ft
Normal Storage757 acre-ft
Drainage Area1 sq mi
Year Completed1920 (106 years old)
NID IDHI00060

Safety Information

High Hazard

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?

Emergency Action Plan: Yes
Last Inspection: October 14, 2021
State Regulated: Yes
Regulatory Agency: DLNR

Ownership

Hawaii Dept of Land & Natural Resources

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Wailua Reservoir?

Wailua 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 Wailua Reservoir?

Wailua Reservoir is owned by Hawaii Dept of Land & Natural Resources (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Wailua Reservoir built?

Wailua 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 Wailua Reservoir?

Wailua 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 Wailua Reservoir?

Wailua Reservoir has a dam height of 40 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 Wailua Reservoir last inspected?

Wailua Reservoir was last inspected on October 14, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.