About 10% of land in Austin is in the floodplain, subject to the dangers of flash flooding. The Floodplain Office administers local and federal development rules, meant to limit damage and protect lives, and maintains floodplain maps and models.

Austin’s floodplains are the areas likely to flood when our creeks rise and flow over their banks. Every creek and lake has a floodplain, regardless of whether it is mapped or not.

Our office maintains floodplain maps and hydrologic and hydraulic models, administers floodplain regulations, provides information to help protect property from floods and reviews applications to build or remodel in the floodplain.

The work we do ensures that Austin is compliant with FEMA rules, protects lives and properties, and allows Austin residents access to more affordable, federally-backed flood insurance.

Floodplain Studies

Floodplains change over time due to development, capital improvement projects and other factors. We periodically restudy watersheds to keep pace with such changes. 

We have begun the process to update floodplains citywide as a result of the Atlas 14 study. This study found that Austin is at increased risk for flooding due to heavier rainfall rates. There is more information about this floodplain remapping effort at ATXFloodplains.com.

In-Depth FEMA Documents Available for Download