Directing urban development to the right places: Assessing the impact of urban development on water quality in an estuarine environment

Abstract The provision of new housing for a growing population is a challenge that many cities and regions all over the world are confronted with. The design and managementof newhousing development is a complex task given it needs to be socially, environmentally and economically sustainable. This paper describes a new method that helps spatially direct new housing development to minimise impact on water quality. Currently, the model accommodates for the pollutants total nitrogen (TN), total phosphorus (TP) and suspended sediments (TSS), but can be extended. The method is based on mathematical programming linked with multi-criteria analysis, and kinematic waveequations. It utilises GIS to underpin multiple spatial constraints on where housing development can take place, and to provide an effective means of visually analysing the impacts of land developmentscenarios produced by the model. We demonstrate the method using a case study for Hornsby ShireCouncil, New South Wales, Australia. With water quality and waterway health being a major issue in any urban development the proposed methodology has wide applications beyond the current study area.