The aim of this work is to validate the hydrological part of the TEB (Town Energy Balance) scheme (Masson, 2000), in using the measurements recorded in the Reze bassin (Nantes, France). The Reze bassin is a residential area of 4.7 Ha, which is made of individual houses and gardens. On this site, hydrological parameters have been continuously collected from 1991 to 1998, specially the riverflows from the sanitary sewer. A 6-year simulation with TEB off-line is done on a single grid point and the runoff term is compared with the observations.

The modelisation of the water exchanges is quite simple in the TEB scheme and supposes that the urban materials are perfectly impervious. The major question is to know if the model should be improved in order to be more realistic or if the simple approach is sufficient.