To avoid leaving it to the insurers themselves to define the sometimes fanciful criteria and to assist city and regional land use planning, the Walloon Region has equipped itself with a complete and scientifically rigorous mapping of the risk of flooding by the overflowing of water courses for the whole of its territory. A long drawn out job carried out by the University of Liège's Aquapôle, and notably by Professor Michel Pirotton's Hydrology, Applied Hydrodynamics and Hydraulic Constructions Unit (HACH).

It is the story, one which is in fact not so common, of the happy intercrossing of the public authorities' will (and budget) and university expertise. Since 2007 the Walloon Region has been equipped with a scientifically rigorous mapping of the risks of flooding for the whole of its territory. A job for which the Region in 2003 allocated a grant to the Centre of Research and Expertise in Water Sciences (Crescendeau-Aquapôle project), whilst specifying its wish that the University of Liège's HACH (Hydrology, Applied Hydrodynamics and Hydraulic Constructions Unit) and its WOLF modelling tool be involved in the process.

'At the genesis of this story were the significant instances of flooding over the last twenty years,' explains Professor Michel Pirotton, the director of HACH. 'Worried by the increase of these extreme phenomena, the Region in 2003 implemented its PLUIES plan (Plan for Preventing and Combating Floods and their Effects on Victims), which made provision for, amongst others, the carrying out of a mapping of the area's flood plains. And it did so because, following floods and rises in water levels, private insurance companies were forced to intervene and carry out their own risk zone mapping work. To avoid having criteria which were too heterogeneous and not always very scientifically rigorous, to aid land use planning and development and to combat these floods in a general way the Region, quite logically, decided to itself define rationally and scientifically the flood risk contingencies.'