Conventional approaches to water supply and wastewater treatment in regional towns globally are failing due to population growth and resource pressure, combined with prohibitive costs of infrastructure upgrades. However, there are complexities associated with implementing sustainable infrastructure solutions, and a need to simplify the decision making process to equally compare alternatives to business-as-usual solutions. The aim of this study was to develop a model which could assist in delivering sustainable infrastructure solu- tions in regional towns (and elsewhere) to facilitate growth and/or reduce the burden on limited resources. The developed model (Sustainable Infrastructure Decision Model, SIDM©) ultimately organises intelligent inputs (from expert stakeholders and quantitative calculations) systematically and holistically in order to compare relative impacts, risks, costs, and benefits of varying solutions. In this sense, it deviates both from the ‘black box’ designs of many other sustainability tools, which requires trust of hidden data and formulas and from heuristic approaches that often ‘set up’ a subjective game of bias between stakeholders. Rather, SIDM© is based on a transdisciplinary system approach which facilitates informed decisions in a transparent manner. It links water, wastewater, energy, and waste (resource flows) along with stakeholders (consumers, producers), the receiving environment (receptors), and governing systems (managers, politicians, regulators, financers). Key to the approach is the use of local context analysis as a ‘design’ driver, along with equal consideration of stakeholder intent, capacity, and commitment. The model also includes an economic analysis and risk-based evaluation process to ensure that the preferred solution is optimised to the environmental, social, economic, and political setting of a particular town. The SIDM© model was applied to a rapidly growing Australian township (Hopetoun) with complex resource and infrastructure constraints, which is described in this paper as a case study. Use of SIDM© resulted in an agreed decentralised solution which was approxi- mately half of the cost of a conventional solution, with considerable water and energy savings and unanimous stakeholder support. Since this project, SIDM© has been applied to other regional towns and urban developments in Australia.
Energy, multicriteria analysis, sustainability decision model, sustainable infrastructure, wastewater, water
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