A GIS-Based 3D Visualization Model to Support Sustainable Urban Land Fund Development Under Observed Flooding and Subsidence Conditions: A Case Study in Binh Chanh Area, Ho Chi Minh City, Vietnam

This study develops and applies a GIS-based 3D visualization model for observed flooding and subsidence conditions to support preliminary spatial screening for sustainable urban land fund development in the rapidly urbanizing Binh Chanh area, Ho Chi Minh City, during the period of 2020–2024. Field-survey records, official flood records, topographic maps, InSAR-based subsidence information, rainfall and tidal records, cadastral data, urban land-use expansion data, and planning information were integrated in a GIS environment. A DEM was generated using IDW interpolation and used as the terrain base for overlaying observed flood-prone locations with elevation, subsidence, road networks, cadastral parcels, urban land-use expansion, and planned urban land fund development areas. The overlaid datasets were then visualized in ArcScene, and an integrated map of observed flooding, subsidence, and urban land-use planning to 2030 was created to support preliminary spatial screening for sustainable urban land fund development. The observed inventory shows an increase in recorded flood-prone locations from 12 in 2020 to 34 in 2024, with maximum recorded flood depth reaching approximately 1.0 m and the largest recorded inundated area approaching 56,000 m2. Areas below 1.2 m elevation account for 80.30% of the study area, while the high and moderately high subsidence classes occupy 57.19%. The proposed approach provides a practical, parcel-linked 3D GIS visualization tool for organizing observed flood information, communicating spatial constraints, and supporting preliminary screening in data-limited urbanizing areas.