Water recycling Via Aquifers - 'Hidden' Storage and Treatment for Cities

Urbanization and population growth results in a greater demand for future water supply, whilst at the same time increases the volume of urban stormwater and wastewater to be managed. Some means of storage is required to recycle stormwater and wastewater in order to balance demand and supply which can often be counter cyclical. Aquifers should be considered as 'hidden' storage for cities; underlying the city they minimize the urban footprint required to store significant quantities of water, are low cost alternatives to surface storage and can provide natural passive treatment analogous to that provided by a slow sand biofilter. This paper documents recent research, which assessed the technical, economic and social feasibility of stormwater and wastewater recycling for both potable and non-potable end-uses. Stormwater harvesting and use at Parafield in Salisbury, South Australia was the main focus of this study and revealed that exposure controls were adequate for stormwater use in public open space irrigation, but appropriate treatments were needed to address health and aesthetic quality for residential third-pipe non-potable supplies and for reticulation within drinking water mains. Stormwater quality data from Parafield were found to be typical of other urban sites, including Orange (NSW), Mount Gambier (SA), and Fitzgibbon (QLD).