Patterson
Key Takeaway
Patterson is classified as significant hazard in California. It was completed in 1962 and is 64 years old. Its primary use is water supply. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 100 ft (taller than 82.2% in CA) |
| Dam Length | 1,306 ft |
| Dam Type | Earth |
| Max Storage | 46 acre-ft |
| Surface Area | 2 acres |
| Year Completed | 1962 (64 years old) |
| NID ID | CA00895 |
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
Alameda County Water District
Local Government
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High Hazard 16 ftFrequently Asked Questions
What is the hazard classification of Patterson?
Patterson 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 Patterson?
Patterson is owned by Alameda County Water District (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Patterson built?
Patterson was completed in 1962, making it 64 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 Patterson?
Patterson serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Patterson?
Patterson has a dam height of 100 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 Patterson last inspected?
Patterson was last inspected on October 18, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.