Developing Flexible Adaptation Pathways for the Peron Naturaliste Coastal Region of Western Australia 2011 - 2012


The Peron Naturaliste Partnership (PNP) is a collaboration of nine local governments (Bunbury, Busselton, Capel, Dardanup, Harvey, Mandurah, Murray, Rockingham and Waroona) between Cape Peron and Cape Naturaliste in the southwest of Western Australia.

The region is potentially subject to erosion and coastal inundation due to climate change and was one of the target areas for the ‘second-pass’ of the National Coastal Vulnerability Assessment.

Building on previous work undertaken in the region, the PNP, with the support of the Western Australian State Government, undertook an economic based analysis of coastal climate change adaptation options for the PNP region.

A preliminary set of studies evaluated the coastal recession risk and the potential for coastal flooding under a set of sea level and storm surge scenarios. Natural extension of the ‘second-pass’ coastal vulnerability studies was their application to coastal risk studies in such a way as to facilitate decision-making with respect to climate change adaptations. An innovative ‘value at risk’ methodology was applied to analyse real options and adaptation measures at regional and local scales. This methodology quantifies the value at risk of traded market assets (houses, farms etc.) and non-traded public assets such as beaches and parks. It also informs a ’decision relevant’ approach that enables local government officers to make use of scarce resources more efficiently to manage short term and longer term economic impacts of coastal hazards, by protecting assets at risk whose value exceeds the costs of protection, and strategically retreating elsewhere.

From the wisdom of hindsight, the scope of the work undertaken was overly ambitious for a single 18-month project, largely due to the considerable difficulties experienced in trying to ‘downscale’ regional hazard data to interpret local coastal change. These difficulties were unforseen given this is an emerging field of enquiry with few documented examples using similar methodologies.

Risks and Impacts Addressed 

Impact of sea level rise, coastal inundation, storm events and riverine flooding to 2100.

Drivers for Adaptation Action 

Previous studies identified the region as highly susceptible to the potential impacts of erosion and coastal inundation due to climate change. This prompted Local, State and Australian Government agencies to undertake a detailed second passstudy, as a targeted area for the National Coastal Vulnerability Assessment.

Outcomes Achieved 

Phase 1 regional hazard assessment incorporated erosion into hazard modelling, identified hot spots at risk and confirmed case study sites for Phases 2 and 3.