This report represents the first part of the second phase of the modelling group activities (Work Package 4200): Simulation results of the best-suited models for Earth Observation data assimilation.This report briefly describes the characteristics of the Arade basin and of the three sub-catchments selected over the Seine basin as well as the database established for the project. This is followed by a description of the model structures, their hydrological process and their main differences.Results in terms of simulated stream flows are analyzed and some conclusions are drawn with a special attention given to the links between model structure/efficiency and model variables/basin characteristics. The last chapter describes, the relationship between the internal states of the model and soil moisture measurements used as a basis for wetness index assimilation, which is the next activity of the project.