Supporting robust decision making on seismic resilience investments: development and trial application of a Decision Support Tool
Report prepared by Bob Kipp, Tracy Hatton, Erica Seville. May 2017. Resilient Organisations Report 2017/02.
The 2010-2011 Canterbury earthquake sequence caused significant damage to the central business district of Christchurch and the nearby suburbs, leading to billions of dollars in damage to buildings and infrastructure and significant psycho-social impacts on the community (Potter, Becker, Johnston, & Rossiter, 2015). For several decades prior to this event, New Zealand had experienced a relatively calm seismic period. Where attention was paid to earthquake resilience, this was primarily focused on the Wellington region and on South Island rural areas expected to be heavily impacted by any Alpine Fault rupture. The Canterbury earthquakes were a reminder that questions around how to reduce the impact of seismic events are relevant to much of the country.
This report outlines the development and use of a prototype decision support tool (DST) developed to guide choices about where to invest time, effort, and resources to maximise improvements to seismic resilience. A decision support tool is a helpful device to indicate strengths, trade-offs, and co-benefits of different types of projects in environments where resources are limited and there is significant uncertainty about risk. The DST is intended to be a usable and robust tool that can aid decision making from problem formulation to identifying a range of suitable actions. The prototype DST is user-focused with an emphasis on engagement and participation.
The design of the DST derives from multi-criteria decision analysis (MCDA), deep uncertainty, decision making for long temporal horizons, and multiple futures scenario modelling, each of which are necessary considerations for low-probability/high-impact events such as major earthquakes. More commonly applied decision support methods, such as cost-benefit analysis, tend to be inadequate in these conditions (Bonzanigo & Kalra, 2014). The combination of multi-criteria decision analysis with techniques designed for navigating complex, uncertain, and perhaps relatively distant futures enables a process of holistic decision making beyond financial costs and benefits.
Seismic resilience refers to a system’s capacity to reduce the impact of earthquakes through mitigation measures and preparedness (Reduce), and increase the capacity of systems to recover quickly from disruptions (Recover) and thrive in the aftermath of disruption (Thrive) (QuakeCoRE, 2016). There are a number of pathways to enhance a system’s ability to reduce, recover, and thrive, and as many alternative pathways that may be more or less effective across multiple criteria. It is up to the decision maker to determine which pathways are optimised to achieve their goals of enhanced resilience.
The DST generates resilience profiles across a portfolio of project pathways. The profiles guide participants through analyses and reflections on the outcomes of their preferences. The DST can be used to generate a deeper understanding of decision makers’ preferences and desired outcomes across a set of pathways, and to determine which pathways align with their preferences.
In this report, we explore the conceptual foundations of the decision support tool, explain how it was created, its main components, and the understanding gained from implementing the DST as a prototype in a workshop format. Finally, we look at future uses, variations and further developments