Feasibility of Recycling Grey-water in Multi-Storey Buildings in Melbourne
Published: 29 October 2012 by MDPI AG in The 2nd World Sustainability Forum session Sustainable Urban Development
Abstract: Australian government has been promoting the use of water conservation and recycling options through several campaigns and offering incentives/grants for such water saving ideas/innovations. One of several water conserving techniques is on-site grey-water recycling for non-drinking purposes. However, even with several awareness campaigns and financial incentives, there is a general reluctance to adopt any grey-water recycling measure. One of the reasons behind this is that people are not aware of the payback period for their initial investment. It is necessary to quantify the expected amount of potable water that can be saved through any particular recycling scheme. As such scheme requires on-site treatment; initial establishment costs are comparatively high. In many cases, developers are not aware of an accurate pay-back period for an initial investment. In this study, feasibility of grey-water recycling in multi-storey buildings in Melbourne was analysed and discussed. The study confirmed the significant potential for reducing the water demand and the benefits that the Melbourne population and water authorities can gain through adopting simple water conservation practices and greywater recycling in multi-story buildings. Usual amount of grey-water generation is much higher than the potential reuse amount. As such it is reasonable that the grey-water would not be collected from all the floors, rather grey-water collection from some floors would be enough to meet the demands of all the floors. The discussion was extended to proposing unique greywater recycling schemes for the Melbourne, involving partial greywater recycling from the higher floors of multi-storey buildings, and locating greywater treatment systems on the roofs of buildings. It is obvious that the cost recovery period of the grey-water treatment system would get shorter with the inclusion of higher number of floors for grey-water recycling. Finally, the effect of number of floors on cost recover periods has been presented. Also, effect of using water conserving devices with the grey-water recycling scheme on cost recovery period has been presented.
Keywords: Potable water, water conservation; greywater recycling; multi-story buildings and cost recovery period