DBPapers
DOI: 10.5593/SGEM2014/B31/S12.103

USE OF GREEN ROOFS AS A WATER RESOURCE

M.Sokac, D. Barlokova, J. Ilavsky, P. Berta
Wednesday 1 October 2014 by Libadmin2014

References: 14th International Multidisciplinary Scientific GeoConference SGEM 2014, www.sgem.org, SGEM2014 Conference Proceedings, ISBN 978-619-7105-13-1 / ISSN 1314-2704, June 19-25, 2014, Book 3, Vol. 1, 807-814 pp

ABSTRACT
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. Apart from this - there is a need to develop and use green roof growing substrates that minimize leaching of nutrients and other contaminants while still providing adequate physical and chemical properties for plant growth. Organic matter included in the substrate is very beneficial for plant growth, but when it decomposes it may leach nutrients. Components such as recycled waste materials and by-products have a potential, but concentrations of contaminants must be considered. This 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. At the same time waste materials are tested, which could be used for the substrate layer for green roof plants. As a suitable material a mixture of dry sludge from municipal waste water treatment plant and peat substrate is tested. Other experiments are focused to the option to add simple filtering device directly into the roof structure, or their placement in the outflow area. Therefore another objective of the project is to explore the use of possible filtration materials (e.g. natural zeolite). This material has excellent absorption ability and together with an activated carbon filter it could create an effective system for green roofs runoff pollution reduction. We assume that water collected this way can be in some cases a valuable source of service water and can be used in many private or commercial applications.

Keywords: green roofs, water resource, water quality, runoff reduction, runoff regulation