Twin Reservoirs

TR-WAIKAEA CANAL OFFSTREAM· Kauai, Hawaii· Built 1920· Earth· 49 ft tall
High Hazard Other Local Government

Key Takeaway

Twin Reservoirs is classified as high hazard in Hawaii. It was completed in 1920 and is 106 years old. Its primary use is other. 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 49 ft (taller than 81.9% in HI)
Dam Length1,810 ft
Dam TypeEarth
Max Storage520 acre-ft
Normal Storage162 acre-ft
Surface Area16 acres
Drainage Area1 sq mi
Max Discharge1,800 cfs
Year Completed1920 (106 years old)
NID IDHI00062

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

County of Kauai - Department of Public Works, Green Aloha Real Estate, LLC, Kapaa 382, Kulana Home Owners Association, Leonard Kaui, Matthew Goodale, Troy & Renee Johnston, Twin Lakes, Waipouli Manoa, LLC

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Twin Reservoirs?

Twin Reservoirs 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 Twin Reservoirs?

Twin Reservoirs is owned by County of Kauai - Department of Public Works, Green Aloha Real Estate, LLC, Kapaa 382, Kulana Home Owners Association, Leonard Kaui, Matthew Goodale, Troy & Renee Johnston, Twin Lakes, Waipouli Manoa, LLC (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Twin Reservoirs built?

Twin Reservoirs 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 Twin Reservoirs?

Twin Reservoirs serves the following purposes: Other. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Twin Reservoirs?

Twin Reservoirs has a dam height of 49 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 Twin Reservoirs last inspected?

Twin Reservoirs 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.