Mcnab
Key Takeaway
Mcnab is classified as significant hazard in California. It was completed in 1947 and is 79 years old. Its primary use is other. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 40 ft (taller than 46.3% in CA) |
| Dam Length | 830 ft |
| Dam Type | Earth |
| Max Storage | 96 acre-ft |
| Surface Area | 7 acres |
| Drainage Area | 3 sq mi |
| Year Completed | 1947 (79 years old) |
| NID ID | CA00561 |
Safety Information
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?
Ownership
Fetzer Vineyards
Private
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Significant Hazard 13 ftFrequently Asked Questions
What is the hazard classification of Mcnab?
Mcnab 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 Mcnab?
Mcnab is owned by Fetzer Vineyards (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Mcnab built?
Mcnab was completed in 1947, making it 79 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 Mcnab?
Mcnab serves the following purposes: Other, Irrigation, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Mcnab?
Mcnab has a dam height of 40 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 Mcnab last inspected?
Mcnab was last inspected on February 3, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.