Hi folks,
I have a LiDAR dataset (ESRI grid / .asc format) and a polygon showing a flood extent. What I want to do is extract the depth information, i.e. space between polygon and DEM, to calculate the flood depth. Unfortunately the polygon has no elevation information, so I have nowhere to start from.
Is there a way to assume the level where the polygon intersects with the LiDAR? My theory is that at the extreme edges of the polygon, where the flood extent finishes (the watermark), the corresponding LiDAR data will be the level of the polygon at that location. If this can be repeated at set intervals around the extent of the polygon, then I could at least start from there.
Any help you could provide would be greatly appreciated.
Thanks,
DK