On the Rise: A Coastal Planning Strategy for Adaption in Response to Climate Change

New Zealand is a long and narrow country with extensive coastline that accommodates many communities. With hot weather getting hotter and wet weather getting wetter, climate change and sea-level rise poses significant risk and change to our coastal environments. With existing properties already at risk and ongoing coastal development pressures, it is necessary to develop local adaptation strategies. Much of the conversation and existing infrastructure focuses on mitigation. Adaption is the least understood climate change response. The shifting and uncertainty of natural systems is often hampered by human control in the form of hard defences. This design-led research portfolio proposes a planning resolution at the interface of mitigation and adaptation. The proposal is not searching for full control by sea walls or for nature to consume, but seeks a synergy and balance between infrastructure and natural systems. The motivation of the scheme is to not only enable residents of a coastal community to continue to occupy the coastal environment, but also develop a plan that accommodates the fluctuations of landscape and thus a more informed and proactive community. The research was initiated by an analysis of current government reports and periodicals providing an understanding of the challenges that face New Zealand’s coastlines. From this, Otaki was selected as a test site, based on the evidence of recent council initiatives that had so far proved unsuccessful. Site visits provided insight into the impact zone and existing contributions to sea-level rise management. South Otaki Beach, around the river mouth, presently experiences flooding during high-water and storm events; due to its low elevation, dune structures and the rivers connection to the sea. Increased water inundation is inevitable with climate change and sea-level rise. Through physical and digital modelling, the design progressed urban and residential scales. The duel urban and residential scales allow the design to shift between the abstract and concrete, constantly questioning the vulnerability, versatility and relevance of the design. On the Rise suggests the development of an elevated landform (a dune shaped dyke) to accommodate the relocation of existing residences from the impact zone. Phased relocation of existing homes is proposed, and clusters of densified dwellings that enable denser occupation in response to the demand for coastal housing and projected population increase will accompany this. The fundamental adaption strategies are: hard protection of several existing houses via a dynamic elevated landform; phased retreat of 61 houses in the impact zone with several of these relocating to the elevated landform; a green buffer zone to accommodate temporary inundation and eventually sea-level rise. An experiential wharf extends over the buffer zone to the existing coastline as an architectural register for measuring, reviewing and observing the impacts of climate change. Through the case study of Otaki, the design highlights the importance of planning strategies that respond to the local (risks, topography and community). It furthermore highlights both the challenges and opportunities with addressing sea-level rise and the potential of increased resilience at the interface of mitigation and adaption