Hesperus Wash (No. 36)

VERDE RIVER - TR· Maricopa, Arizona· Built 1973· Earth· 36 ft tall
High Hazard Flood Risk Reduction Local Government

Key Takeaway

Hesperus Wash (No. 36) is classified as high hazard in Arizona. It was completed in 1973 and is 53 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 36 ft (taller than 64.5% in AZ)
Dam Length1,060 ft
Dam TypeEarth
Max Storage482 acre-ft
Normal Storage0 acre-ft
Surface Area28 acres
Drainage Area3 sq mi
Max Discharge11,800 cfs
Year Completed1973 (53 years old)
NID IDAZ00074

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: December 8, 2020
State Regulated: Yes
Regulatory Agency: ARIZONA DEPARTMENT OF WATER RESOURCES

Ownership

TOWN OF FOUNTAIN HILLS

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Hesperus Wash (No. 36)?

Hesperus Wash (No. 36) 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 Hesperus Wash (No. 36)?

Hesperus Wash (No. 36) is owned by TOWN OF FOUNTAIN HILLS (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Hesperus Wash (No. 36) built?

Hesperus Wash (No. 36) was completed in 1973, making it 53 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 Hesperus Wash (No. 36)?

Hesperus Wash (No. 36) serves the following purposes: Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Hesperus Wash (No. 36)?

Hesperus Wash (No. 36) has a dam height of 36 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 Hesperus Wash (No. 36) last inspected?

Hesperus Wash (No. 36) was last inspected on December 8, 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.