Angwin

Moore Creek· Napa, California· Built 1967· Earth· 35 ft tall
High Hazard Water Supply Irrigation Private

Key Takeaway

Angwin is classified as high hazard in California. It was completed in 1967 and is 59 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 35 ft (taller than 38.2% in CA)
Dam Length621 ft
Dam TypeEarth
Max Storage156 acre-ft
Surface Area14 acres
Drainage Area0 sq mi
Year Completed1967 (59 years old)
NID IDCA01038

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: March 9, 2022
State Regulated: Yes
Regulatory Agency: DWR, Division of Safety of Dams

Ownership

Pacific Union College

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Angwin?

Angwin 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 Angwin?

Angwin is owned by Pacific Union College (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Angwin built?

Angwin was completed in 1967, making it 59 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 Angwin?

Angwin 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 Angwin?

Angwin has a dam height of 35 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 Angwin last inspected?

Angwin was last inspected on March 9, 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.