When is Drone Photogrammetry Useful for Flood Risk Assessment?

Abstract

Drone technology and the high resolution datasets it enables stand to revolutionize our understanding of the Earth’s surface. This research is Houston specific, and studies how drones can be used to systematically collect photogrammic data to detect environmental changes, and how that data is valuable for flood planning purposes. This data is the culmination of three years of research. Prior to this year, the focus has been learning to fly the drone, learning the image processing Pix4D and ArcMap 10.5, and creating a workflow for accurate image collection processing. This study has collected three separate datasets of the study area at Buffalo Bayou using a DJI Phantom 4 Pro drone. This data was then processed and modeled in Pix4D to create digital elevation models (DEMs). The DEMs were calibrated and analyzed in GIS, and compared to the publicly available 2018 LIDAR data. Our research catalogs high resolution change over time of our study area, and documents the process of how drones can be used to systematically observe change over time. Additionally, our data highlights the difference in resolution between a low elevation drone flight versus a higher elevation LIDAR scan.