The goal is to present an estimation of potential flooded area. But still keeping it simple.
I know this will not be accurate. The question is:
- will it be good enough for at gestimate / rough guideline? I am aware this is a crude method.
I am using QGIS.
I want to create flood area polygons of n m^3 of water. e.g. polygons showing the max. area that will be flooded if xx m^3 water is released.
- raster DEM
- m^3 of water to be released
- convert DEM raster layer to polygons based on elevation (in steps on 1m because of the DEM resolution).
- set the area of the polygons as an attribute
- create an volume attribute (area * 1m^3) to get an estimate of how much water the area will hold.
- optionally rescaling the polygons to get estimations for volumes lesser than the polygon but greater than the "inner" smaller polygon (e.g. in fractions of 10).