Residential potable and recycled water end uses in a dual reticulated supply system

The need to understand, model and predict urban water consumption is paramount, particularly with urban densities increasing throughout the world. Specifically, it is vital to determine potable water savings, daily demand patterns and actual end use water consumption experienced in diversified water supply schemes in order to verify planning estimates and justify the future application of such schemes. This paper details the results of a mixed methods (quantitative and qualitative) end use investigation, pre- and post-commissioning of recycled water, in a dual reticulated supply scheme in the master planned Pimpama Coomera region, Gold Coast, Australia. Recycled water, supplied for irrigation and toilet flushing, accounted for 59.1 L/p/d or 32.2% of total consumption post-commissioning, with irrigation being 28.9 L/p/d or 15.7%. Furthermore, developed end use diurnal patterns demonstrate the unique daily demand consumption within the region and significant reductions in peak potable water demand when compared with single reticulated supply areas. The paper concludes with discussions of implications for better informed water services infrastructure planning activities. ► Residential water end use break down pre- and post-commissioning of recycled water in a dual reticulated supply scheme in the Gold Coast, Australia. ► Recycled water accounted for 59.1 L/p/d or 32.2% of total consumption post-commissioning, with irrigation being 28.9 L/p/d or 15.7%. ► End use diurnal patterns demonstrate unique daily demand consumption within a dual reticulated region. ► Significant reductions in dual reticulated average day peak hour potable water demand when compared with single reticulated supply areas.