Implementing Pre-Emptive Managed Retreat: Constraints and Novel Insights

Abstract

Purpose of Review Managed retreat will be inevitable where other adaptation options, such as protective structures or building restrictions, provide only temporary respite or are otherwise uneconomic, technically impractical or both. Here, we focus on the implementation of pre-emptive managed retreat, providing examples of how it can be sequenced, socialised and given the governance enablers necessary for implementation. Recent Findings Ongoing sea-level rise during the twenty-first century and beyond poses huge adaptation challenges, especially for low-lying coastal and floodplain settlements. Settlements are already functionally disrupted from repetitive non-extreme flooding and research shows that sea-level rise will impact far more people, far sooner than previously thought, as more powerful storms, heavy rainfall and rising groundwater coincide with higher tides. To date, most examples of managed retreat have been post-disaster responses following damage and disruption. Pre-emptive managed retreat, by contrast, has yet to become a well-accepted and widely practised adaptation response. Nevertheless, there are increasing examples of research and practice on how pre-emptive managed retreat can be designed, sequenced and implemented alongside other forms of adaptation within anticipatory forms of governance. Summary The current state of knowledge about managed retreat is reviewed and critical insights and lessons for governance and policy-making are given. Several novel examples from New Zealand are presented to address some of the implementation gaps. Goals and principles are enunciated to inform long-term adaptation strategies.

A comparative analysis of hazard-prone housing acquisition programs in US and New Zealand communities

“…Research conducted by New Zealand scholars suggests that future acquisition programs should employ robust governance strategies that reduce complexity across different property acquisition mechanisms and provide a nationally consistent and transparent allocation of decision-rights across the tiers of government (Boston and Lawrence 2017;Lawrence et al 2020). The ability to balance governance strategies that are undergirded by existing planning laws points to the value of pre-event planning for buyouts and managed retreat in order to facilitate plan consistency in advance.…”

Territorial governance of managed retreat in Sweden: addressing challenges

“…It includes the successive relocation of assets to safer ground and restoration of the land that is left behind and return it to nature (Koslov 2016;Hino et al 2017;Neal et al 2017;Rulleau and Rey-Valette 2017;Braamskamp and Penning-Rowsell 2018;Owen et al 2018;Griggs and Patsch 2019;Siders 2019a and b). The basic idea lies in increasing society's resilience (to flooding) by allowing a dynamic shoreline, which will benefit long-term socio-economic development as well as the environment (Siders et al 2019;World Economic Forum 2019;Lawrence et al 2020). Managed retreat has been implemented at several places around the world, for example, in Australia (Niven and Douglas 2013), China (Pittock and Xu 2011), France (Rulleau and Rey-Valette 2017), New Zealand (Owen et al 2018), UK (Esteves 2014;Myatt et al 2003), USA (Dyckman et al 2014;Freudenberg et al 2016) and the Pacific Island countries (Campbell et al 2005).…”

“…The problem exists at two levels: who should pay and be compensated today and how should the costs be distributed between current and future generations. Other examples of barriers are land and water rights, conflicting interests, limited available land for relocation, identity, beliefs and perspectives (Gibbs 2013;Hino et al 2017;Lindegaard and Funder 2017;Lovett 2017;Rulleau and Rey-Valette 2017;Owen et al 2018;Lawrence et al 2020). These barriers are also apparent in Sweden.…”

“…Although managed retreat is becoming a subject to a large body of international research (e.g. Esteves 2014;Rulleau and Rey-Valette 2017;Schliephack and Dickinson 2017;Siders et al 2019;Siders 2019a, b;Doberstein et al 2020;Johnson 2020;Lawrence et al 2020;Tubridy et al 2020), it is still in its infancy in Sweden and is rarely mentioned as an alternative in Swedish climate adaptation strategies, action plans and measures at local, regional or national levels. An exception is the climate adaptation plan for the southernmost region in Sweden issued by Skåne County Administrative Board (Länsstyrelsen 2014) which highlights the need to explore more closely the possibility to let the beach retreat and let erosion take its place to form a new coastline.…”

Preparing for Sea-Level Rise through Adaptive Managed Retreat of a New Zealand Stormwater and Wastewater Network

“…Several councils in New Zealand are currently starting to implement or develop managed retreat strategies, as an adaptation to ongoing compound natural hazards at the coast. Hence, in some locations, retreat will be an inevitable response due to physical and affordability constraints and it has been judged prudent in national guidance and directions to manage such a response to avoid further unavoidable damage, disruption, public safety, and losses [23,24].…”