Duncan

Tr Pit River· Modoc, California· Built 1919· Earth· 19 ft tall
Low Hazard Water Supply Irrigation Private

Key Takeaway

Duncan is classified as low hazard in California. It was completed in 1919 and is 107 years old. Its primary use is water supply.

Physical Details

Dam Height 19 ft (taller than 14.1% in CA)
Dam Length900 ft
Dam TypeEarth
Max Storage2.6K acre-ft
Surface Area353 acres
Drainage Area11 sq mi
Year Completed1919 (107 years old)
NID IDCA00480

Safety Information

Low Hazard

No probable loss of human life and low economic/environmental losses expected.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: No
Last Inspection: June 17, 2022
State Regulated: Yes
Regulatory Agency: DWR, Division of Safety of Dams

Ownership

Milano Land and Cattle Company, LLC

Private

Nearby Dams

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Fairchild (Res F)

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Cloverswale

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Carpenter Wilson

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Kelley Hot Spring Fish

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Reservoir N

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Jack'S Swamp Dam No. 2

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Reservoir M

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Frequently Asked Questions

What is the hazard classification of Duncan?

Duncan is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Duncan?

Duncan is owned by Milano Land and Cattle Company, LLC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Duncan built?

Duncan was completed in 1919, making it 107 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 Duncan?

Duncan serves the following purposes: Water Supply, Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Duncan?

Duncan has a dam height of 19 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 Duncan last inspected?

Duncan was last inspected on June 17, 2022. 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.