Flood analysis with GIS

2. Preprocesssing data

Before we can start our flood analysis, we need to preprocess the datasets. The following preprocessing steps are needed:

• Clip DTM
• Interpolate voids
• Extrude buildings

Let's start with organizing the data.

1. Start QGIS 3.34.

2. Open the project of the first tutorial.

3. Hide all layers.

4. Select the following layers with the Control key pressed: 

• buildings
• DTM_Rotterdam
• DSM_Rotterdam

5. Click right on the selection and choose Group Selected from the context menu.


6. Name the group Flood analysis and drag the group to the top.