The former BHP Beenup titanium minerals operation is in the biodiverse Scott River region in southwest Western Australia and was closed prematurely in 1999 after only two years of operation. Significant modifications to the landscape (including deep dredging to 55 m, lime sand blending with the natural soils to mitigate acid generation) combined with limited previous knowledge of the recruitment biology of many of the plant species, created significant uncertainty as to the feasibility of restoring the site to near-natural communities. This paper covers two aspects of the closure process: (1) a novel planning approach undertaken for setting the end use and target ecosystems using a designed based philosophy informed by risk assessment, and (2) the assessment of restoration success using ecological completion criteria. In terms of planning and design, the geomorphic and biodiversity features of the regional landform types (dunes, plains, sumplands, damplands etc.) formed the basis of design of closure sites. These regional ecosystems were surveyed in detail to characterise the soils, hydrology and vegetation of each major feature, with these ecological relationships then used to develop rehabilitation design criteria. Artificial landforms (deep pools created by dredging) were modified into lakes via void infilling and the creation of extensive shallow shorelines to generate a more naturalistic final shape. The focus on ecosystem design enabled revegetation to be tailored to the specific vegetation communities that best matched the reconstructed landforms; this significantly reduced seed wastage and increased the probability of success. As far as we are aware, it is the first project of this scale in Australia that has successfully created a functional range of wetland types similar to the surrounding natural wetlands. In terms of performance assessment, a detailed and prescriptive set of restoration and completion criteria were developed to enable a greater certainty of outcomes and enabled quantitative measurements of restoration success. The incorporation of sustainability and resilience, which are global indices of success used in ecological restoration projects outside of mining, were applied here to guide both the approach to restoration (so as to enable the site to adapt to changing climates and unpredictable events) and to the measurement of success (completion criteria). This was one of the first instances globally to embed these ecological concepts as key success categories for rehabilitation. Fifteen years after restoration, 15 ecological communities and more than 251 plant species have been successfully restored, including many conservation-listed species. The project achieved regulatory sign off against rehabilitation completion criteria in 2018 and is one of the few 'ecologically designed' post-mining landscapes globally.

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Water sector reform is one of the cornerstone requirements of resilient cities in the face of global climate change and in meeting the commitments of the UN Sustainable Development Goals by 2030. However, on the current trajectory, countries are falling short and will either need to commit to significant capital investment to supplement large-scale central networks and supplies or make rapid changes to adopt decentralized technologies and business models. Water utilities represent a significant and influential group, particularly in Australia, Europe, and the USA where they are monopolistic within their jurisdictions and strongly

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 solutions 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 approximately 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.