Runoff quality from green roofs

Green roofs have many advantages: improving the roof thermal insulation, noise absorption, temperature and humidity control in cities (urban microclimate), fire resistance and protection of roof structural surface layers against UV- radiation. The most important green roof ability, which appears as a key feature in terms of rainwater management in urban catchments is the ability of rainwater detention and retention. To increase the retention capacity of green roofs are being used in addition to the drainage layer and the storage layer, which in hydrological terms significantly change the properties of these roofs. Paper describes preliminary results of a scientific project VEGA 1/0691/13, focused on experimental research of the hydrological function of green roofs in urban areas with regard to the reduction and the detention of rainfall runoff, which may be one of the crucial factors for sustainable urban development. Another objective of the research is to test the filtration ability of green roofs, rainwater runoff quality and possible use of green roofs as a supplementary source of service water in urban areas. We assume that runoff water collected from green roofs can be in some cases a valuable source of service water and can be used in many private or commercial applications.