Thompson Creek
Key Takeaway
Thompson Creek is classified as high hazard in California. It was completed in 1928 and is 98 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 | 66 ft (taller than 71.1% in CA) |
| Dam Length | 1,500 ft |
| Dam Type | Earth |
| Max Storage | 543 acre-ft |
| Surface Area | 345 acres |
| Drainage Area | 4 sq mi |
| Year Completed | 1928 (98 years old) |
| NID ID | CA00198 |
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
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High Hazard 18 ftFrequently Asked Questions
What is the hazard classification of Thompson Creek?
Thompson Creek 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 Thompson Creek?
Thompson Creek 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 Thompson Creek built?
Thompson Creek was completed in 1928, making it 98 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 Thompson Creek?
Thompson Creek 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 Thompson Creek?
Thompson Creek has a dam height of 66 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 Thompson Creek last inspected?
Thompson Creek was last inspected on November 16, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.