Mast

Tr Cahto Creek· Mendocino, California· Built 1963· Earth· 85 ft tall
Significant Hazard Water Supply Irrigation Private

Key Takeaway

Mast is classified as significant hazard in California. It was completed in 1963 and is 63 years old. Its primary use is water supply. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 85 ft (taller than 77.8% in CA)
Dam Length580 ft
Dam TypeEarth
Max Storage380 acre-ft
Surface Area14 acres
Drainage Area0 sq mi
Year Completed1963 (63 years old)
NID IDCA00972

Safety Information

Significant Hazard

No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.

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

Emergency Action Plan: No
Last Inspection: June 8, 2022
State Regulated: Yes
Regulatory Agency: DWR, Division of Safety of Dams

Ownership

Private Entity

Private

Frequently Asked Questions

What is the hazard classification of Mast?

Mast is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Mast?

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

When was Mast built?

Mast was completed in 1963, making it 63 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 Mast?

Mast 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 Mast?

Mast has a dam height of 85 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 Mast last inspected?

Mast was last inspected on June 8, 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.