The 3D buildings were extracted from LiDAR data collected by the City of Calgary but there were no attributes and the type of file of 3D buildings was a geodatabase. Based on what happened with flooding in 2013 the City of Calgary inspectors wanted to know in the event of future flooding, the lowest elevation of the houses or buildings to inspect right away to determine if the building is affected or not by the flooding. The elevations gathered were:
1. The lowest ground elevation of the building (x, y and z).
2. The highest ground elevation of the building (x, y and z).
3. The highest elevation of the building (x, y and z).
These elevations were calculated for more than 400,000 buildings in the City of Calgary and the whole process to gather the elevations were processed from 2 different workbenches, one using the DEM to extract the ground elevations and the other workbench was using the real 3D building elevations to calculate the highest point from every single building.
City of Calgary
FME World Tour 2016