A Test of Harnessing Roofwater for Non-potable Uses at a Residential District in Hangzhou

摘要

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 m~2 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.