Modeling & Mapping Program

State Program

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 in order 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 and the need for improved flood risk mapping, and leveraging the available statewide coverage of LiDAR elevation data the TWDB has chosen the Base Level Engineering (BLE) approach as a key path forward for Texas. BLE is an efficient approach that FEMA and its partners have developed to complement the traditional floodplain mapping approach. The TWDB is aiming for complete statewide BLE coverage by Fiscal Year 2024. In order to coordinate the resources needed to support this comprehensive effort, a new division entitled Flood Science and Community Assistance was formed. The division consolidated existing departments supporting grant coordination and community assistance and added two flood risk data focused departments called Flood Modeling and Flood Mapping. The modeling and mapping groups primarily focus on delivering the statewide BLE mapping while also providing technical support to other flood and engineering related programs throughout the agency.

Federal Program

The Cooperating Technical Partners program is an effort launched by the Federal Emergency Management Agency (FEMA) in 1999 to increase local involvement in developing and updating Flood Insurance Rate Maps (FIRMs), Flood Insurance Study reports and associated geospatial data. The TWDB has served as the state Cooperating Technical Partner since 2000 and is supporting FEMA’s Risk Mapping, Assessment and Planning (Risk MAP) program.

Activities and Tasks

  • Hydrologic and Hydraulic modeling
  • Base Level Engineering (BLE) Mapping
  • BLE Project Management
  • Texas Flood Risk Data Compilation
  • Detailed engineering analysis for DFIRM updates
  • Partner support to FEMA Risk MAP program
  • Benefit cost analyses
  • Flood grant application reviews

For the flood modeling and mapping staff contacts, please visit the Flood Science and Community Assistance Staff page.