The aim of this research is to investigate the consequences of restoring the natural drainage conditions in an alluvial plain for soil water quentity and quality and habitat conditions. The area of research is a backland on the banks of the R. Dijle. Up until now, the backland has been drained by the R. Leigracht but that will be drastically reduced from 10/99 on by a change in the local river network and then the backland will become a lot wetter. In this research, the present and changed conditions in a transect from R. Dijle to R. Leigracht will be investigated. These data will be used to calibrate and validate the numerical model UNSATCHEM-2D. The model can then serve as an instrument for scenario-analysis and the processes which play an important role in the change of habitat conditions upon rehumidification can be identified.