One of the major issues for assessment of the long-term sustainability of urban areas is related to the concept of \imported sustainability". In order to produce such an assessment for a given territory, one must rst identify and quantify the types of materials used, and the impacts associated to these uses. Material Flow Analysis (MFA) is directly related to how the material circulates and how it is transformed within a territory. In most cases this analysis is performed at national and regional levels, where the statistical data is available. The challenge is to establish such an analysis at smaller scales, e.g. in the case of France, at the department or city level. Currently, few studies are done at these scales and when they exist, they are based on the extrapolation of data at the country or the region levels. In this thesis, the possibility of applying data analysis at the regional level by generating a mathematical model that can t well the data at regional scale and estimate well the departmental one is explored. The downscaling procedure relies on the assumption that the obtained model at level 'n' (for example region) will be also true at level 'n+1' (for example department), such that it could properly estimate the unknown data based on a set of chosen drivers. The tests show that it is very important to choose the proper drivers and the class of model.