Nature in cities. Renaturalization of riverbanks in urban areas

Most of the rehabilitations of river sections with their banks in cities has often been inappropriate. The reason for this is that designers do not understand the natural functioning of a river and they are synthesizing and sterilizing these urban spaces, distorting its natural functioning. Besides, there are clear proofs that these rehabilitations are useless, contributing to the devaluation of the river ecosystem without improving its relationships with the city. The other effect of the water lines destructions are the educational terms, broadcasting a wrong idea of the functioning of the river. This article tries to show briefly, how a river works, what arethe natural characteristicswhich should be valued by a rehabilitation and what has gone wrong in recent rehabilitation works. Using the theoretical drawings, based on examples from real life, and supported by photographs, the authors present also the possible negative consequences of the urban mistakes for the sake of operating of cities. The paper shows some techniques of natural engineering, using natural materials and vegetation that may be employed. This may become a green intervention, making these techniques much more economic and educational, improving life quality thanks to public access to attractive parks and squares by rivers.