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3.2
Terrain preprocessing
A. Fill Sinks
• Select Terrain preprocessing → Fill Sinks.
•
Confirm that the input of RawDEM (also referred to as the unfilled DEM) is ‘dem_jhik’. The output of
the HydroDEM is ‘FillGrid’. ‘FillGrid’ is a default name that can be renamed by the user. Remember
the name of HydroDEM if you change the default name.
•
Click OK. (This step takes some minutes.)
The output data will be saved in the subfolder ‘BaseData’ within the folder where the project is saved.
•
Click OK.
•
The result of the fill sinks operation is the ‘Fillgrid’ theme; the lowest cell elevation is increased from 790 to
798 metres.
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Resource Manual on Flash Flood Risk Management – Module 2