What are effective design guidelines for protecting small, low-lying New Zealand coastal towns from climate-change induced flooding? : A dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Landscape Architecture at Lincoln University

Abstract

In Aotearoa New Zealand more than 75% of the population are situated within 10 kilometres of the coast (Hayward, 2008). With global temperatures on the rise, climate change-related hazards are projected to increase in frequency and severity. Additionally, sea levels are expected to rise by 0.3-1.1 meters by the year 2100 (Hernández-Delgado, 2015; NIWA, n.d; O'Donoghue et al., 2021; Oppenheimer et al., 2019; Rouse et al., 2017). Low-lying, small coastal communities face an amplified risk of flooding caused by climate change, due to a lack of infrastructure and limited funding available to local councils, compared to larger cities (James M. Fitton et al., 2021). At present, larger cities have greater access to mitigation strategies and tools for coping with coastal flooding in the face of climate change (Lamb et al., 2019). Furthermore, little is known about the effectiveness of design guidelines to assist landscape architects to implement appropriate design strategies in small coastal towns. Strategies include design guidelines. Design guidelines refer to recommendations or principles that designers can use to ensure that their designs are effective for their intended purpose (Nijhuis & de Vries, 2019). Firstly, a narrative literature review was conducted to develop an understanding of what was known and not known about strategies for mitigating climate change induced flooding, as well as determining whether design guidelines for flooding in small coastal towns exist. Secondly, an evaluation of existing guidelines was conducted following Kennedy Evans (2019) ‘best practice Landscape Architecture design guideline criteria' to determine their effectiveness. A set of suggestions to improve existing guidelines were proposed based on the results of the evaluation in conjunction with the narrative literature review. Māpua, New Zealand was chosen as the case study site for this research as it is highly prone to flooding due to its biophysical characteristics. An inventory and analysis was made of all existing biophysical and land-use characteristics to determine to what extent Māpua met the best practice flooding design guidelines that were proposed. The guidelines were then applied to the site at a regional, masterplan and intermediate scale to demonstrate how the improved design guidelines can be applied to protect a small coastal town. Thus demonstrating what effective guidelines are to protect small, low-lying coastal towns from climate-change induced flooding.