Anticipating staged managed retreat at the coastal margins

Abstract

Managed retreat in coastal areas involves the landward relocation of existing and planned development to reduce exposure to hazards. The hazard risk is reduced or removed entirely, leaving the coast to respond to natural processes. The New Zealand Coastal Policy Statement (NZCPS) 2010 provide directives to local government to consider such approaches (Objective 5; policies 25 and 27), amongst a suite of options for reducing coastal hazard impact on existing and future development. Similar provisions were present in the NZCPS 1994, however, managed retreat approaches still remain a 'black box' for many and New Zealand has few successful examples of managed retreat of habitable dwellings at the coast. There is a pressing need to examine managed retreat more closely as a viable, or the only, alternative for sites at intractable risk of erosion and flooding. Here we seek to unpack the black box of managed retreat as a mainstream option for coastal risk management.