Millett Swale

MILLET SWALE· Navajo, Arizona· Built 1958· Earth· 24 ft tall
High Hazard Flood Risk Reduction Debris Control Private

Key Takeaway

Millett Swale is classified as high hazard in Arizona. It was completed in 1958 and is 68 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 24 ft (taller than 42.3% in AZ)
Dam Length2,500 ft
Dam TypeEarth
Max Storage2.1K acre-ft
Normal Storage0 acre-ft
Surface Area200 acres
Drainage Area40 sq mi
Max Discharge6,120 cfs
Year Completed1958 (68 years old)
NID IDAZ00059

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: April 23, 2020
State Regulated: Yes
Regulatory Agency: ARIZONA DEPARTMENT OF WATER RESOURCES

Ownership

Silver Creek Irrigation District

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Millett Swale?

Millett Swale 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 Millett Swale?

Millett Swale is owned by Silver Creek Irrigation District (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Millett Swale built?

Millett Swale was completed in 1958, making it 68 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 Millett Swale?

Millett Swale 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 Millett Swale?

Millett Swale has a dam height of 24 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 Millett Swale last inspected?

Millett Swale was last inspected on April 23, 2020. 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.