- Integrated information system for the hydrological management in the Walloon region: digital cartography, use of satellite imagery and modelling

Context and objectives

The Service for Hydrological Studies (SETHY) of the Walloon region is mandated to execute the following tasks :
(1) real-time - hydrological observations, prediction and monitoring of high water levels and flow-rates, distribution of information and warnings if necessary;
(2) contribution to river management by generating statistics and through simulation studies.
For the execution of these tasks, SETHY disposes of a network of hydrological stations for measuring water levels and gathering rainfall data. The collected data are stored in a centralised databank.

The integration of the existing databank in a GIS allows study of the spatial aspects of the hydrological phenomena. The global system consists of 2 components :
1) a geographical part containing a cartographic database and a (satellite) image database;
2) a library of hydrological models and modules for parameter calculation.
SETHY has acquired the SWRRBWQ (Simulator for Water Resources in Rural Basins - Water Quality) model, which is based on the Soil Conservation Service (SCS) method.

Project outcome

Expected scientific results

- Hydrological GIS, mainly containing data in raster format :
maps, digital elevation model (DEM), and derived maps : simplified soil map, hydrographical network, slope classes, soil occupation classes, hydrological groups of soils (SCS method), cultural factor C (Wischmeier), Manning rugosity factor n on slopes (SCS), runoff parameters (SCS),
- derived from satellite images : land cover/use map and hydrological land cover map (SCS)
- limnimetric and rainfall data from the network of hydrological stations
Computer programmes for extraction of data from the GIS as input for the hydrological model.
Maps for the test watersheds of the Hermeton, Lesse, Mehaigne, Salm.
Hydrological model adapted to Belgian conditions.
Simulation of daily mean flow rates and peak flow rates at the village Our in the watershed of the Our (70 km2) over 11 years, using the adapted hydrological model.

In the future, the GIS will serve as a supporting tool for decision making in various fields of application in the domain of water management in the Walloon Region, such as nitrate discharge.

Project leader(s): ULg - Gembloux Agro-Bio Tech - Echanges Eau-Sol-Plante
Location: Region:
  • Walloon Region