Managed Retreat Components and Costing in a Coastal Setting

Climate change impacts are beginning to be felt across the world. Therefore, the development and understanding of adaptation options is becoming more important. Sea-level rise and its associated impacts are predicted to continue and accelerate well into the next century. As such, it is important that adaptation options which reduce risks associated with sea-level rise are developed and are well understood. Managed retreat is one such option. While research on managed retreat is increasing, there is a lack of literature that identifies what managed retreat comprises, how to plan and stage the option over time, and how to cost it as an adaptation option. This thesis aims to address this gap in the literature by answering the following three questions: (1) what are the issues related to implementing managed retreat as an adaptation strategy in coastal areas, now, and moving into the future?; (2) what are the components of managed retreat?; and (3) what framework could be developed for costing managed retreat? A qualitative ‘desk-top’ approach was taken to deconstruct the components of managed retreat across space and time and to develop a framework for costing the components as part of an adaptation strategy. An in-depth analysis of literature, enabled an understanding of managed retreat implementation, and also informed the development of a component typology and costing framework for the adaptation option. The typology and framework were then tested for relevance and utility for decision making through a series of semi-structured discussions with key informants working in climate change adaptation. Using the component typology and costing framework, a new approach is presented for staging and costing managed retreat, over time and in different contexts. The typology and framework contribute knowledge and guidance for local governments and infrastructure agencies when discussing managed retreat with their communities, for identifying and staging managed retreat, and for the costing of components. It does this by presenting components in stages as overlapping and parallel pathways, providing groupings of components according to types of costs, and identifying appropriate costing methodologies that enable the implementation of managed retreat. To conclude, the thesis suggests areas for future research on managed retreat.