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Community Bot
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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.

Output

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.

##Input

Input

  • raster DEM
  • m^3 of water to be released

Process

  1. convert DEM raster layer to polygons based on elevation (in steps on 1m because of the DEM resolution).
  2. set the area of the polygons as an attribute
  3. create an volume attribute (area * 1m^3) to get an estimate of how much water the area will hold.
  4. 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).

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.

Output

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.

##Input

  • raster DEM
  • m^3 of water to be released

Process

  1. convert DEM raster layer to polygons based on elevation (in steps on 1m because of the DEM resolution).
  2. set the area of the polygons as an attribute
  3. create an volume attribute (area * 1m^3) to get an estimate of how much water the area will hold.
  4. 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).

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.

Output

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.

Input

  • raster DEM
  • m^3 of water to be released

Process

  1. convert DEM raster layer to polygons based on elevation (in steps on 1m because of the DEM resolution).
  2. set the area of the polygons as an attribute
  3. create an volume attribute (area * 1m^3) to get an estimate of how much water the area will hold.
  4. 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).
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HC Haase
HC Haase
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Simplified flood "model" / estimation from elevation data

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.

Output

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.

##Input

  • raster DEM
  • m^3 of water to be released

Process

  1. convert DEM raster layer to polygons based on elevation (in steps on 1m because of the DEM resolution).
  2. set the area of the polygons as an attribute
  3. create an volume attribute (area * 1m^3) to get an estimate of how much water the area will hold.
  4. 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).