Designing a lot scale stormwater system with rainwater tanks and WSUD: Possible upgrade of design practices to enhance sustainability of urban water cycle

摘要

Council development control plans (DCP) in the Western Sydney region do not actively promote the use of rainwater tanks (RWT) for stormwater control. In addition, the majority of councils in this region require, in the design of stormwater system, the assumption of a full RWT. Furthermore, the design often needs to incorporate infiltration devices and should maintain the post-development flow to pre-development levels. This is often achieved with the use of on-site detention and some sort of infiltration device. This paper discusses the implications of a recent research of RWT on the current stormwater design practice in the Western Sydney region. The research indicated that up to the 1 in 1 year ARI runoff events can be contained in the RWT designed to be used for toilet flushing, laundering and irrigation. It is argued that for innovative design to occur the DCPs of the local councils need to have greater flexibility to allow RWT to be used as a means of stormwater control device. Recommendations are made in this paper to upgrade the current design practices to enhance the sustainability of urban water cycle.