Maui Reservoir 21

FED BY IRRIGATION GULCH· Maui, Hawaii· Built 1913· Earth· 22 ft tall
High Hazard Irrigation Private

Key Takeaway

Maui Reservoir 21 is classified as high hazard in Hawaii. It was completed in 1913 and is 113 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 22 ft (taller than 18.1% in HI)
Dam Length950 ft
Dam TypeEarth
Max Storage72 acre-ft
Normal Storage57 acre-ft
Surface Area7 acres
Drainage Area0 sq mi
Max Discharge175 cfs
Year Completed1913 (113 years old)
NID IDHI00071

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 18, 2021
State Regulated: Yes
Regulatory Agency: DLNR

Ownership

MP East B, LLC, a Delaware limited liability company

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Maui Reservoir 21?

Maui Reservoir 21 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 Maui Reservoir 21?

Maui Reservoir 21 is owned by MP East B, LLC, a Delaware limited liability company (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Maui Reservoir 21 built?

Maui Reservoir 21 was completed in 1913, making it 113 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 Maui Reservoir 21?

Maui Reservoir 21 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 Maui Reservoir 21?

Maui Reservoir 21 has a dam height of 22 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 Maui Reservoir 21 last inspected?

Maui Reservoir 21 was last inspected on October 18, 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.