The DTM 1m, digital terrain model at 1m-resolution, is a homogeneous and regular point grid indicating the height of the ground level in order to model its surface, without taking into account objects on the surface such as buildings and vegetation. DTM 1m is achieved by interpolating in Lambert 2008 source data in Lambert 72 and at a 1m-resolution from the Flemish (2013-2015) and Brussels (2021) Regions, and by adding Lambert 2008 data at 1m-resolution from the Walloon Region (2021-2022).

The DTM 5m, digital terrain model at 5m-resolution, is a homogeneous and regular point grid indicating the height of the ground level in order to model its surface, without taking into account objects on the surface such as buildings and vegetation. The DTM 5m is the result of the assembly of different data coming from various sources and with different coordinate systems and resolutions. The DTM 1m is achieved by interpolating in Lambert 2008 source data in Lambert 72 and at a 1m-resolution from the Flemish (2013-2015) and Brussels (2021) regions, and by adding Lambert 2008 data at 1m-resolution from the Walloon Region (2021-2022). The DTM 5m is obtained by resampling of the DTM 1m. In addition, the DTM 5m is improved and updated internally using direct photogrammetric surveys based on the most recent aerial photographs.

An hillshade is a homogeneous and regular points grid, indicating the grey tone deriving from their orientation relative to the chosen fictitious light source. The Hillshade DTM 1m is a representation of the hillshading of the DTM 1m.

An hillshade is a homogeneous and regular points grid, indicating the grey tone deriving from their orientation relative to the chosen fictitious light source. The Hillshade DSM 1m is a representation of the hillshading of the DSM 1m.

The DSM 1m, digital surface model at 1m-resolution, is a homogeneous and regular point grid indicating the height of the Earth’s surface level in order to model its landscape, also including objects on the surface such as vegetation and buildings. The DSM 1m is achieved by interpolating in Lambert 2008 source data in Lambert 72 and at a 1m-resolution from the Flemish (2013-2015) and Brussels (2021) Regions, and by adding Lambert 2008 data at 1m-resolution from the Walloon Region (2021-2022).

This dataset contains the orthophoto mosaics that were created following the floods of July 2021 in the valleys of the Vesdre, the Meuse and the Demer. Orthophotos are aerial photographs that have been geometrically corrected (orthorectified) to eliminate distortions caused by terrain relief, lens distortion, and camera tilt. Unlike raw aerial imagery, orthophotos have a uniform scale and accurate geometry, making them suitable for cartography, measurements, and visual analysis. This specific dataset includes orthophotos based on aerial photographs acquired in July 2021 by Hansa Luftbild, commissioned by the National Geographic Institute (NGI), following the floods in the zones of the Vesdre, a part of the Meuse downstream of Liège and the Demer. The resulting orthophoto mosaics are georeferenced in the Lambert 2008 coordinate system. All orthophotos are in colour (RGB). The ground resolution (GSD) is 6.5 cm (4 cm above the Hoëgne). The spatial coverage of this dataset is limited to the affected zones. The data can be visualized via the corresponding web service (WMS). The data is available on request via https://ngi.be/aanbod/kaarten-en-fotos/luchtfotos-orthofotos/.

The hillshades are presented as a regular homogeneous grid of points indicating the grey level value resulting from their orientation with respect to the chosen fictitious light source. The 1m hillshade is the view obtained by hillshading of the 1m DTM. The 5m and 20m hillshades are the views obtained by hillshading of the 5m and 20m DTM.

DSM 1m is a homogeneous and regular point grid indicating the height of the Earth’s surface level in order to model its landscape. DSM 1m is achieved by interpolating in Lambert 2008 source data in Lambert 72 and at a 1m-resolution from the Flemish and Brussels Regions, and by adding Lambert 2008 data at 1m-resolution from the Walloon Region.

This dataset shows a digital surface model. It is a homogeneous and regular points grid which indicates the height above the surface of the earth, either the soil or any other permanent and visible element in the landscape (vegetation, construction,…). These data represent the situation of the landscape resulting from the July 2021 floods in het areas of the Vesdre, of part of the Meuse downstream from Liège and of the Demer.

The DTM is a homogeneous and regular point grid indicating the height of the ground level in order to model its surface. The DTM 1m is achieved by interpolating in Lambert 2008 source data in Lambert 72 and at a 1m-resolution from the Flemish and Brussels regions, and by adding Lambert 2008 data at 1m-resolution from the Walloon Region. The DTM 5m has an additional source, namely drawn structure lines and points adapted during systematic and continuous update by photogrammetric surveys. The DTM 20m is obtained by resampling of the DTM 1m.