Bridging the Water Supply-Demand Gap in Australia: a Desalination Case Study

Abstract

Water supply in Australia mainly relies on precipitation and, therefore, is highly dependent on climate variability and change. Coupled with reduced rainfall reliability, population and economic growth and increasing competition for water resources augment the concern over the existing water resources and put a strain on future water security. In fact, the upward trend of water demand has already been escalating the pressure on water resources. Clearly, the anticipation of decline in water supply requires the identification of more reliable, rainfall-independent supply alternatives. Thus, concern about the increase in demand and decrease in supply is steering Australian water authorities to consider a range of policy options, such as desalination plants. For this research, we present a modelling framework using System Dynamics approach to incorporate a range of factors into a simulation of future water demand and supply in Queensland, Australia, and examine desalination schemes as long-term water security option in the portfolio of supply sources. Simulation modelling frameworks focus on demand, supply, climate change and extreme events, population growth, and impacts of desalination plants on water supply as there are strong interdependencies between these factors. The model evaluates current and future conditions under a range of scenarios, including construction of new desalination plants, changes in precipitation due to climate change, water restriction, and population growth. The proposed approach would help decision makers to develop sustainable water supply and efficient infrastructure strategies, and thus respond to water scarcity in a timely manner to avoid the costly interventions.