Analysing water sensitive urban design options

Abstract

Planning for ‘water-sensitive’ infill development has become a priority for sustainable urban development in Australia. With city growth, infill development in vacant or under-used land parcels is becoming a dominant mode of development. However, the current ‘knock-down-rebuild’ approach to such development will undermine resource efficiency, liveability and urban amenity, particularly for natural water systems. There is a need to identify development options that are more water sensitive. To better analyse water efficiency and hydrological performance of Water Sensitive Urban Design (WSUD) options, we use a water mass balance evaluation framework to demonstrate the ‘whole of water cycle’ approach. The new insights gained were the extent to which the proposed WSUD options impact the water metabolism performance of the urban area through modelling the water mass balance of eight selected WSUD options within different scenarios, involving pre-development (1825), current (2016), before and after water-sensitive options in 2031. The novel contribution is the development of one new hydrological performance indicator, open space ratio and redeveloped other four water metabolism indicators to assess water performance in infill development. Results show that urbanisation dramatically altered the water flows, like stormwater runoff. Also, road space plays an important role in future solutions.