Application of sustainability assessment framework for flood mitigation projects: case study on a flood levee project in Queensland, Australia

Sustainable development of floodplains is closely linked to the sustainable flood mitigation measures. Various sustainability assessment (SA) methods to evaluate the influence of policies, plans or projects towards sustainable development have been emerging in recent years; however, most of them are national or regional policies and programs. Very few research studies have been carried out for sustainability assessment of flood mitigation projects. This paper presents the concept of a proposed sustainability assessment framework for flood mitigation projects and its application to a recently implemented flood levee project in Australia. This research has employed a review of the life cycle of flood mitigation projects, sustainability assessment methodologies, consultations with experts, and a case study of flood mitigation projects. In line with the project life cycle, the proposed sustainability assessment framework is developed incorporating five stages: a) contextualizing the project, b) SA during planning and implementation, c) SA during flood event, d) SA at periodic intervals, and e) SA at modification phase or changing to a new project. The application of the SA framework to the first two stages of a flood levee project demonstrates how the best suitable alternative levee option can be chosen in the planning stage by determining a sustainability index (SI) of the possible alternatives using a set of sustainability indicators. The study also shows achievement towards sustainability of the finally implemented project which can be compared with the originally planned project using the SA framework. The application of the SA framework suggests the potential for better decision making for individual flood mitigation projects, taking into account the sustainable outcome of the project as well as linking this to regional sustainable development.