SET Proceedings 2978-4387 Caravel Press 10.65582/set.2005.033 2005.033 A Test of Harnessing Roofwater for Non-potable Uses at a Residential District in Hangzhou ChengGang LiuYingyun JiangMing ZhengZongXi School of architecture resource and envirnoment engineering, NanHua University, HengYang, China ZheHua architecture design firm, HangZhou 23092005 4 1 978-7-112-07718-2 149 152 23 September 2005 © 2005 Copyright WSSET 2005

Water demands are constantly increasing in HangZhou because of industrial development and increasing population. Hence, there is a continuous search for new sources and one such source is roofwater from high-rise buildings. In this paper the experiment of collecting the roofwater from the south spine of a residential district in HangZhou was done and utilising it for non-potable uses was discussed, too. A well-established simple input-output model incorporating a dual-mode system (DMS) of operation has been used so as to ensure that all the collected roofwater from an area of 18,75 m2 is used only for non-potable purposes. The design parameters were optimized leading to a rainwater storage tank linked to the existing water tanks with pump cut-in and cut-out electrodes placed at depths of 1 and 1.5 m above the base of the tank that will ensure that the supply of water will always be available for the non-potable uses.

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