Urban Flood Management Using the Green Roof System (Case study: Tehran City)

With the expansion of construction and impermeable surfaces in large cities, the urban flood phenomenon is considered an important problem. various cities in iran have recently been affected by floods and damages, which are high-intensity rainfall and inefficient drainage networks. this study aimed to provide urban flood management solutions concerning the various advantages of green roofs and the environmental, climatic, and geographical characteristics of the tehran metropolis. for this purpose, the types of green roofs and their components have been analyzed using the content analysis method. the novelty of this research is in prioritizing the use of green roofs according to their advantages, especially the feature of optimizing the urban sewage network, and according to the price range of their different types. the result is that the construction and implementation of green roofs in order to take advantage of the optimizing the urban sewage system and reducing runoff require special policies and methods of encouragement and punishment, which should be used by all governmental and non-governmental organizations and also according to the precipitation patterns in the areas with flood risk should be used with an extensive green roof. however, due to the high cost of intensive green roofs in some cases, this type of roof can be used in new buildings with large and expensive areas. due to the slope of tehran and the pattern of canals and runoff, green roofs in the north and east of tehran city are a priority.