Thannas Dam
Thannas Dam is an earth dam located in Travis County, Texas, built in 1984. It carries a High hazard potential classification and has a fair condition assessment.
About Thannas Dam
Thannas Dam is a dam in Travis, Texas. The dam is owned by City Of Austin (local government). It impounds the Off Channel.
The dam stands 17 feet tall, and has a maximum storage capacity of 50 acre-feet. Completed in 1984, the structure is 42 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 05/02/2023.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Texas dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Texas |
| County | Travis |
| River/Stream | Off Channel |
| Coordinates | 30.17558, -97.75588 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 17 ft |
| Dam Height | 17 ft |
| Year Completed | 1984 (42 years old) |
Storage & Hydraulics
| NID Storage | 50 acre-ft |
| Max Storage | 50 acre-ft |
| Max Discharge | 2 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Owner | CITY OF AUSTIN |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 05/02/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | TX07338 |
| Federal ID | TX07338 |
| More Info | State Dam Safety Program |