Assessing sustainable development of flood mitigation projects using an innovative sustainability assessment framework

Sustainability assessments of flood mitigation projects are crucial for achieving sustainable development of floodplains. This article presents the application of an innovative sustainability assessment (SA) framework for flood mitigation projects throughout its life. The research employed a literature review, consultation with experts, and a case study of a flood mitigation project in Australia. The sustainability assessment framework includes five stages: (a) contextualizing the project; (b) SA at the planning and implementation stage; (c) SA during a flood event; (d) SA at regular intervals; and (e) SA during a change or modification phase. The results of the sustainability assessment at the first two stages of the flood mitigation project suggest how the sustainability index (SI) could be used to choose the best design options. Also, the study presents how the achievement toward sustainability of the finally constructed project could be compared with the planned project using the SI score. Sustainability assessment at Stages 3–5, carried out with possible scenarios, demonstrates that the project's sustainability could be hindered by the growing number of vulnerable population and property development in the floodplain without an upgrade of the project. The findings suggest the applicability of the SA framework for better decision‐making for sustainable flood risk management.