Copperopolis

Penney Creek· Calaveras, California· Built 1905· Earth· 33 ft tall

Key Takeaway

Copperopolis is classified as high hazard in California. It was completed in 1905 and is 121 years old. Its primary use is water supply. 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 33 ft (taller than 35.9% in CA)
Dam Length600 ft
Dam TypeEarth
Max Storage225 acre-ft
Surface Area24 acres
Drainage Area1 sq mi
Year Completed1905 (121 years old)
NID IDCA00845

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: May 24, 2022
State Regulated: Yes
Regulatory Agency: DWR, Division of Safety of Dams

Ownership

Private Entity

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Copperopolis?

Copperopolis 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 Copperopolis?

Copperopolis is owned by Private Entity (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Copperopolis built?

Copperopolis was completed in 1905, making it 121 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 Copperopolis?

Copperopolis serves the following purposes: Water Supply, Fire Protection, Stock, Or Small Fish Pond, Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Copperopolis?

Copperopolis has a dam height of 33 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 Copperopolis last inspected?

Copperopolis was last inspected on May 24, 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.