Diaz, Nicholas David (2020-08). Deriving first floor elevations (FFEs) within residential communities located in Galveston using RTK-UAS based data. Master's Thesis. Thesis uri icon


  • Flood damages occur when just one inch of water enters a residential household and models of flood damage estimation are sensitive to first floor elevation (FFE). The current sources for FFEs consist of costly survey-based elevation certificates or assumptions based on the year built and foundation type. We sought to address these limitations by establishing the role of an RTK enabled UAS platform in deriving FFEs. Four residential communities within Galveston Island were chosen based on location, elevation differences, and structure types. A Phantom 4 RTK was used to obtain georeferenced aerial imagery of these communities to create detailed 3D models within Pix4D with +/- 0.02 m horizontal and +/- 0.035 m vertical accuracies. From these residential community models, ground, FFEs, and nearest drainage road elevations were obtained. Our findings, show that the RTK enabled UAS approach is an efficient, cost-effective method in establishing accurate FFEs in residential communities. This data can be used to further understand flood risks and damage at the household level.

publication date

  • August 2020