Mansfield Dam
Mansfield Dam is an earth dam located in Travis County, Texas, built in 1942. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Mansfield Dam
The primary purpose of Mansfield Dam is flood risk reduction. The dam is designed to control downstream flooding by temporarily storing excess water during storms and releasing it at a controlled rate. The dam is owned by Lower Colorado River Authority (local government). It impounds the Colorado River near Austin.
The dam stands 278 feet tall and stretches 7,089 feet across, creates a reservoir covering 18,929 acres, has a maximum storage capacity of 3,223,000 acre-feet, and collects water from a drainage area of 38,130 square miles. Completed in 1942, the structure is well-established, with more than 75 years of service.
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 satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 11/11/2022.
At 278 feet, this dam is taller than 99% of all dams in the United States.
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 |
| Nearest City | Austin |
| River/Stream | Colorado River |
| Coordinates | 30.39222, -97.90734 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 278 ft |
| Dam Height | 277 ft |
| Dam Length | 7089.4 ft |
| Year Completed | 1942 (84 years old) |
Storage & Hydraulics
| NID Storage | 3,223,000 acre-ft |
| Max Storage | 3,223,000 acre-ft |
| Normal Storage | 1,953,900 acre-ft |
| Surface Area | 18,929 acres |
| Drainage Area | 38,130 sq mi |
| Max Discharge | 608,000 cfs |
Ownership & Safety
| Purpose | Flood Risk Reduction |
| Owner | LOWER COLORADO RIVER AUTHORITY |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 11/11/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | TX01087 |
| Federal ID | TX01087 |
| More Info | State Dam Safety Program |