It is now 25 years since the IPCC Common Methodology was first applied to the Western Australian coast (Kay et al. 1992) to look at the challenge presented by sea level rise to longer-term coastal management. This assessment, like other applications of the Common Methodology, highlighted that there were local attributes which should be considered when transferring the findings to planning policy. This broad finding was equally supported by the Australian Coastal Vulnerability Assessment Project (Waterman 1996), in which a series of case studies around the Australian coast integrated locally relevant coastal hazard assessment with response to sea level rise.
Despite scientific recognition of diversity, the concurrent trend in coastal management policy was towards unification of approach, with most Australian State Governments outlining very similar methods for calculation of coastal hazard zones (Walsh et al. 2004). Consequently, it is unsurprising that the National Coastal Vulnerability Assessment, NCVA (DCC 2009) applied a uniform method of estimating coastal hazard. However, it is arguably equally unsurprising that the results of the NCVA were strongly related to coastal morphology, matching the broad findings of the previous ACVAP. Subsequent research has highlighted the range of techniques available for coastal vulnerability assessment (Woodroffe et al. 2012), but to date, selection of techniques is more commonly driven by information availability and budget than by underlying processes. National classification schemes such as the Australian Beach Classification (Short 2006) and Australian Sediment Compartments Project (Thom et al. 2016) are possibly synergistic with the vulnerability assessment methods, but presently require more detailed consideration before such application.
At a State Government level, similar pressures of scientific divergence and policy-based unification have applied to the evaluation of coastal hazards, through development and application of the State Coastal Planning Policy SPP2.6 (WAPC 2001, 2003, 2013). Efforts to create flexibility within the policy to account for coastal diversity have been partly stymied, either by the perceived need for firm regulatory frameworks, or the commercial benefits accrued by using a repetitive process of assessment.
The present format of SPP2.6 has been developed to incorporate risk management frameworks, through development and application of Coastal Hazard Risk Management and Adaptation Plans (CHRMAP) for sites deemed exposed to coastal hazard. Recognition of the need for flexibility is incorporated in the CHRMAP guidelines (WAPC 2014), which follows from local government applications to support coastal management decision-making (CZM & Damara WA 2008, 2011; CZM et al. 2013, Damara WA 2013). However, regulatory application of the policy has demonstrated the difficulty of applying a flexible approach, with focus on statistically robust hazard assessments and limited attention paid to the basis for adaptive decision-making.
Synthesis of previously completed coastal vulnerability assessments within Western Australia has suggested that more effective use of resources can be brought to CHRMAP development through systems understanding of the active processes, values, available information and decision-making objectives. Constraint potentially provided by each of these factors suggests the need to identify whether the CHRMAP should be strategic, targeted or detailed at an early stage. This project aims to develop frameworks and an evidence base to support cost-effective scoping of CHRMAP.
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