Import 3D cross sections from QGIS to HEC RAS

In the HEC RAS ​​training courses that I run, the question of optimizing the building of the models comes out regularly. In this post, I detail a way to import profiles across streams available in the form of 3D polylines in HEC RAS ​​to speed up this build process. The detailed approach here is certainly not the only solution, nor necessarily the optimal approach, but it is based on free and easily accessible tools. Goal : Generate HEC RAS ​​.csv file for importing cross sections from 3D...

From real time modelling to crisis management

I have already written here two articles dealing with the experimental flood forecasting pilot set up in partnership with GEOMOD around the solution ICM Live (sorry, only available en French for now) : Real-time modeling: the article briefly describes the operation of an automated modeling system Cascading simulations: this article presents the principle of simulations triggered at the detection of certain events in data flows or in a simplified global simulation We will address here in...

ICM - correct mesh errors

This post is part of a series of articles about modeling coupled 1D / 2D river and urban water and models optimizations 2D modeling are consuming resources and computing time, it is therefore essential to work with own grids, and optimize them. This requires the following checks: avoid computational elements uselessely too small, ie which do not provide relevant information for the purpose of the study. This point is important, it is in fact the size of the smallest element of calculation...

ICM Live - cascading simulations

Efficient hydraulic modelling implies some compromises between : The size of the modelled region The spatial resolution and accuracy of the results The "cost" of these simulations, in terms of computer time and power In order to maintain a balance between these elements, it can be of interest to setup models working at different scales, that can interact. Cascading models : The example below exploits 2 different models : → a hydrological model : Setup at a large scale, it allows...