Big Dalton
Key Takeaway
Big Dalton is classified as high hazard in California. It was completed in 1929 and is 97 years old. Its primary use is flood risk reduction. 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 | 153 ft (taller than 90.4% in CA) |
| Dam Length | 480 ft |
| Dam Type | Multi-Arch |
| Max Storage | 1.3K acre-ft |
| Surface Area | 26 acres |
| Drainage Area | 4 sq mi |
| Year Completed | 1929 (97 years old) |
| NID ID | CA00187 |
Safety Information
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?
Ownership
Los Angeles County Department Of Public Works
Local Government
Nearby Dams
Big Dalton Debris Basin
Los Angeles, CA
High Hazard 59 ftMorgan Debris Basin
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High Hazard 37 ftLittle Dalton Debris Basin
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High Hazard 71 ftSan Dimas
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High Hazard 131 ftPuddingstone Diversion
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High Hazard 34 ftSan Gabriel
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High Hazard 320 ftLive Oak Reservoir
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High Hazard 105 ftWeymouth Memorial Reservoir
Los Angeles, CA
High Hazard 18 ftFrequently Asked Questions
What is the hazard classification of Big Dalton?
Big Dalton 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 Big Dalton?
Big Dalton is owned by Los Angeles County Department Of Public Works (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Big Dalton built?
Big Dalton was completed in 1929, making it 97 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 Big Dalton?
Big Dalton serves the following purposes: Flood Risk Reduction, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Big Dalton?
Big Dalton has a dam height of 153 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 Big Dalton last inspected?
Big Dalton was last inspected on November 18, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.