SUMMARY
The objective of this paper is to determine the evolution of impervious surfaces in four sites inCluj-Napoca, identify sources of pollution of rainwater runoff, and identify areas in which can beimplemented bioretention cells, the results serving to the development of an efficient bioretention cell.This model should take into account the local characteristics and promotion of sustainable managementpractices of urban rainwater runoff. In order to establish the degree of coverage with impervious surfacesand the evolution of impervious surfaces in a nine years period, in the city of Cluj-Napoca, have beenselected four sites. The following types represent urban locations chosen for research: commercial areas,industrial areas, high-density residential areas, low-density residential areas. The results obtained showthat these sites have various characteristics in terms of land use, the degree of coverage with impervioussurfaces, the evolution in time of impervious surface, the sources of pollution and the size of areas inwhich bioretention cells can be implemented. The types of studied sites have provided the possibility toobtain information that will serve to develop accurate implementation models of bioretention systems,with the possibility of extending them in the other areas of Romania, (specifying will be needed minimumadjustments depending on the climate characteristic, land use, pollution etc.).