The aim of the TRHYBU project is to identify the impact of urbanization on the hydrological response of watersheds during flood and low-water periods.

Indeed, even if impacts of urbanisation on hydrological processes are well know at local scale (increase of surface runoff and decrease of infiltration), the impact of urbanisation at catchment scale is more difficult to understand. The presence of more permeable surfaces as well as spatial organisation of those surfaces and wastewater network can largely regulate hydrological response. Literature demonstrates that the urbanisation impact on hydrology at catchment scale remains an open question. Even if in general, urbanisation seams to increase intensity of high-flow and severity of low-flow period, there are still some studies showing contrary conclusions. This project aims to go beyond the priori by using a large database of catchments which is exploring different configuration of European and North American catchments.