Rainwater tank analysis tools, climatic and spatial variability: a case study for Sydney

This paper presents analyses from a recently developed daily water balance model (eTank), which calculates rainwater tank outcomes under three different climatic conditions (i.e., dry, average and wet years). For comparison, eTank calculated results were compared with two other continuous simulation type water balance models, CSWBM and 'Raintank Analyser'. It is found that CSWBM produced water savings and reliabilities significantly at variance with the eTank calculated water savings and reliabilities. However, it is shown that a widely used tool, 'Raintank Analyser', calculated water savings that closely match the eTank calculated water savings in an average year, which is reasonable and supports eTank's accuracy. Further, eTank was used to present expected climatic variations in water savings in Sydney, as well as expected spatial variations within the city.