STORM BASIN MANAGEMENT FOR A FLOODING EVENT IN AN UNGAUGED CATCHMENT

摘要

The implementation of the Water Framework Directive (WFD), which asks to manage catchments in an integrated way, is a very challenging task. Therefore new tools facilitating the implementation of the WFD at the catchment level are needed. One of them is a Decision Support System (DSS). In this paper we present a case study of small ungauged catchment of the Nethen river (Belgium) which was used as a pilot study for hydrological modelling of a decisional problem. The main focus of this paper will be on stakeholder involvement in the initial phase, hydrological aspects of the catchment, decisional problems and finally the modelling and data preparation for the DSS development. The Nethen catchment is quite particular as a small runoff flooding occurs very frequently. Unfortunately creation of new storm basins has not solved the inundation problem. Some organizational changes took place in Walloon Region after the WFD was adopted. Therefore the initial phase of the project was concentrated on involving the environmental protection stakeholder into hydrological issues. The hydrological modelling was quite new to the stakeholder. Quite a lot of effort was put into data preparation, modelling and finally to understand the way stakeholder is operating at the catchment level. The major problems encountered were connected with 'translation' of hydroinformation into real situations. The biggest challenge was the fact that the pilot catchment is an ungauged one. The final result of the modelling was very satisfactory; on one hand we as scientists were able to understand certain political limitations of management of the water resources at the catchment level. On the other hand stakeholder was able to implement computer programs that are facilitating the decisional process.