#TerrainModeling

2025-12-02

#DniproHesFlood
🛰️ Dam-break modelling with GRASS GIS

I used the r.damflood module in GRASS GIS on a historical scenario:
the destruction of the DniproHES dam by Soviet forces in August 1941 during their retreat from Ukraine.

I reconstructed a pre-war DEM of the Dnipro River from old topographic maps, modeled the dam structure, and created a breach raster.

Using r.damflood, I simulated the propagation of the flood wave over the first 24 hours after the dam explosion.
Based on this model, I generated a visualization showing the wave dynamics.

All tools used are fully open-source.
The results have not yet been published anywhere.

#Geospatial #GIS #HistoricalGIS #DigitalHistory #Cartography #OpenData #DataAnalysis #DEM #TerrainModeling #Hydrology #DamBreak #Dnipro #DniproHES #Ukraine #Zaporizhzhia #QGIS #SAGAGIS #GRASS #FOSS4G

2025-11-20

Geospatial analysis and modeling is not only about:
1. downloading Copernicus data,
2. generating pretty maps,
3. calling it “analysis”.

In reality it often means years of collecting and reconciling heterogeneous data from different eras: digitizing historical maps, fixing coordinate systems, validating geometry through indirect evidence. This stage can easily take more time than all later modeling.

The images show how I digitized and georeferenced 1920s–1940s topographic maps of the lower Dnipro region. After transforming them into a unified coordinate system, I used them to reconstruct the pre-flood terrain (before the Kakhovka Reservoir).
That DEM later became the basis for modeling the 1941 DniproHES dam-break wave.

…This data-preparation phase alone took me almost four years.

#Geospatial #GIS #HistoricalGIS #DigitalHistory
#RemoteSensing #Cartography #OpenData #DataAnalysis #DEM #TerrainModeling #Hydrology #DamBreak #Dnipro #DniproHES #Ukraine #Zaporizhzhia #QGIS #SAGAGIS #GRASS #FOSS #DniproHesFlood

Digitized German WWII topographic map (scale 1:50,000) of the Zaporizhzhia and Khortytsia area, with modern village names overlaid. Used for reconstructing pre-flood terrain.A collage of Soviet, German, and other historical maps showing different vintages of cartographic detail.Historic German black-and-white aerophotograph of the destroyed DniproHES dam (1941) overlaid on a color-coded DEM used for modeling the dam-break wave.A German topographic map of Zaporizhzhia with a mask marking the reconstructed water flow zone during the modeled dam-break.

Client Info

Server: https://mastodon.social
Version: 2025.07
Repository: https://github.com/cyevgeniy/lmst