Thannas Dam
Key Takeaway
Thannas Dam is classified as high hazard in Texas. It was completed in 1984 and is 42 years old. 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 | 17 ft (taller than 23.1% in TX) |
| Dam Type | Earth |
| Max Storage | 50 acre-ft |
| Normal Storage | 0 acre-ft |
| Max Discharge | 2 cfs |
| Year Completed | 1984 (42 years old) |
| NID ID | TX07338 |
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
CITY OF AUSTIN
Local Government
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What is the hazard classification of Thannas Dam?
Thannas Dam 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 Thannas Dam?
Thannas Dam is owned by CITY OF AUSTIN (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Thannas Dam built?
Thannas Dam was completed in 1984, making it 42 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.
How tall is Thannas Dam?
Thannas Dam has a dam height of 17 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 Thannas Dam last inspected?
Thannas Dam was last inspected on May 2, 2023. Inspection dates indicate when a formal review occurred, not the results of that inspection.