Flood risk maps are considered vital tools for land use planning in flood-prone areas. There are several ways to map flood risk. Some of the most well-known flood risk data sets are those produced by the Federal Emergency Management Agency (FEMA) and its partners. These maps are called Flood Insurance Rate Maps (FIRMs) and help determine rates for flood insurance and are used by communities to manage flood risk by regulating development in or near the floodplain. The Texas Water Development Board (TWDB) has a flood mapping program that is focused on compiling and disseminating reliable flood data to influence informed decision making at regional and local levels. The Flood Mapping team works with FEMA, communities, and other mapping partners to develop and share a variety of flood data.
During the 86th Legislature, Senate Bill 500 was passed which allocated funds from the floodplain management account in the Texas Infrastructure Resiliency Fund to the TWDB to develop and update flood risk maps in the state using current data and technology standards. Additionally, these funds will be used to support the development of a state flood plan and to provide up to date flood hazard information for the state. Considering this new legislation, the need for improved flood risk mapping, and leveraging the available statewide coverage of Light Detecting and Ranging (LiDAR) elevation data, the TWDB has chosen to develop Base Level Engineering (BLE) flood models and maps as a key path forward to identifying flood risk in Texas. BLE is an efficient approach that FEMA and its partners have developed to complement the traditional floodplain mapping approach. The TWDB aims to have flood hazard data development from BLE completed for the entire state of Texas by 2024.
For additional information on the TWDB's BLE approach and status, please contact Flood Modeling and Mapping staff.