Flow-R is software for rapid, reliable, and user-friendly propagation modeling of natural hazards. Flow-R allows rapid assessment of the propagation area based on several published empirical run-out models at local and regional scales. It is optimized for regional susceptibility mapping of gravitational hazards, such as:
Flow-R supports susceptibility mapping to depict areas prone to natural hazards. These maps are, therefore, an essential tool for land-use planners to identify quickly and efficiently settlements, infrastructure, and communication networks potentially threatened by natural hazards.
Flow-R uses a probabilistic approach to model the propagation of gravitational hazards from user-defined source areas. It results in the total perimeter encompassing all possible propagations, which leads to susceptibility maps that are similar to the reach probability used in hazard mapping.
Flow-R includes a wide range of algorithms for the lateral spreading of a mass movement coupled with several simple friction models that control the run-out distance of the flow.
Up to date with recent academic research, Flow-R has demonstrated the capability to model reliable and realistic propagations for different gravitational hazards on various scales.
The protective effect of forests or other mitigation measures can be assessed by spatial variations of the travel angle.
The choices of the datasets and the algorithms are open to the user, which makes it compliant with various applications and available datasets. Required input data are a Digital Elevation Model and a raster file with the source areas prepared in any GIS software. All common types of raster files are supported by Flow-R.
The generated output files are saved as raster files or shapefiles for further treatment with any standard GIS tool.
Fast and versatile software for gravitational hazards run-out assessment
Flow-R comes in two versions: Flow-R Pro & Flow-R Lite
|Flow-R Pro||Flow-R Lite|
|All algorithms available|
|Efficient multi-threaded computation|
|Efficient memory management|
|All common raster file types as input|
|Automatic regridding of source areas|
|Maximum size of the study area||unlimited||5 million DEM cells*|
|Filter source areas based on cell values||customizable**||fixed (> 0)|
|Maximum number of runs in queue||unlimited||3|
* or 500 km² for a DEM with a cell size of 10 m; ** =, >, <, ≥ or ≤ any value; *** limited to susceptibility (max and sum), velocity and energy.
The full-featured demo version is valid for 30 days and restricted to non-commercial applications. Furthermore, the size of the study area is restricted to 0.5 million cells (or 50 km² for a DEM with a cell size of 10 m) and the queue is limited to three runs.
Flow-R Pro and Flow-R Lite are available in different license types and pricing plans: monthly and yearly subscriptions or perpetual purchase, as well as personal and flexible (floating) licenses.
|Monthly subscription||Yearly subscription||Perpetual license|
|Flow-R Pro Personal||150 EUR||500 EUR||1000 EUR|
|Flow-R Pro Flexible||220 EUR||750 EUR||1500 EUR|
|Flow-R Lite Personal||60 EUR||200 EUR||400 EUR|
|Flow-R Lite Flexible||100 EUR||350 EUR||700 EUR|
Taxes may still be added. The tax rate depends on your country tax rules, entered tax identification number (e.g. VAT ID), and selected purchase method. Discounts for multiple licenses (3+: 5%, 5+: 10%). Personal: Installation on a single computer. Flexible (floating): Installation on multiple computers with concurrent use. Perpetual license: With updates for the current major version. It is possible to add restrictions based on IP ranges. Please contact the support.
Program participants must agree to use the software for educational and research purposes only. Please complete this form to determine your eligibility for the academic version of Flow-R and then to access the dedicated offers.
Download files for a hands-on tutorial
Subscription management and billing: https://terranum.onfastspring.com/account
Licenses management: https://licenses.terranum.ch/
Report a bug: https://bugs.terranum.ch
Suggest improvement or a new feature: https://suggest.terranum.ch
Horton P, Jaboyedoff M, Rudaz B and Zimmermann M: Flow-R, a model for susceptibility mapping of debris flows and other gravitational hazards at a regional scale. Natural Hazards Earth System Sciences, 13, 869-885, 2013, doi:10.5194/nhess-13-869-2013
Flow-R was originally developed at the University of Lausanne. Terranum is now in charge of its development and provides related support in various domains:
There may be situations where Flow-R needs to be modified in order to meet the requirements of a certain project, or to model a specific behaviour. We are ready to make the necessary adjustments in Flow-R in order to meet your needs.
Although Flow-R is optimized for regional applications, nation scale modeling requires a significant amount of processing time. Terranum possesses a cluster in order to perform intensive calculations.
We have now various experiences using Flow-R in different conditions, with varying data quality and for multiple hazards. Being the editor of the model, we also know perfectly the behaviour of the different algorithms.
Having some help when starting using Flow-R is a time saving option. We have some courses ready and will be happy assisting you.
Introduction of a variable travel angle in Flow-R in order to take into account the effect of forests on rockfall propagation
2014 | Canton of Fribourg, Switzerland
Indicative hazard mapping of debris-flows, snow avalanches, rockfalls and landslides for the Canton de Fribourg
2014-2015 | Canton of Fribourg, Switzerland
Investigation on DEM resolutions effects on the processing of the Norwegian snow avalanche susceptibility maps using α⁄β and Perla's models implemented in RAS and Flow-R
2015 | NVE, Norvège