Black Canyon Diversion

PAYETTE RIVER· Gem, Idaho· Built 1923· Concrete· 183 ft tall
High Hazard Hydroelectric Irrigation Federal Government

Key Takeaway

Black Canyon Diversion is classified as high hazard in Idaho. It was completed in 1923 and is 103 years old. Its primary use is hydroelectric. 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 183 ft (taller than 97.4% in ID)
Dam Length1,040 ft
Dam TypeConcrete
Max Storage29.8K acre-ft
Normal Storage29.8K acre-ft
Surface Area1,100 acres
Drainage Area2,680 sq mi
Max Discharge39,060 cfs
Year Completed1923 (103 years old)
NID IDID00282

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: February 25, 2020
State Regulated: Yes
Regulatory Agency: IDWR

Ownership

RECLAMATION

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Black Canyon Diversion?

Black Canyon Diversion 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 Black Canyon Diversion?

Black Canyon Diversion is owned by RECLAMATION (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Black Canyon Diversion built?

Black Canyon Diversion was completed in 1923, making it 103 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 Black Canyon Diversion?

Black Canyon Diversion serves the following purposes: Hydroelectric, Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Black Canyon Diversion?

Black Canyon Diversion has a dam height of 183 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 Black Canyon Diversion last inspected?

Black Canyon Diversion was last inspected on February 25, 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.