## Estimating Resiliency Benefits of Road Upgradation: Case of the East Road in Malaita, Solomon Islands

# I. Introduction

Infrastructure resilience may be characterized as the capacity to plan for and effectively respond to both short-term disaster shocks and long-term effects of climate change in a manner that minimizes service disruption and reduces the associated costs – financial, economic, environmental, and social – on society. Resilience capacity depends on the physical resistance of an infrastructure asset to natural hazards, as well as the processes in place to help facilitate safe and rapid recovery, and the safeguarding of financial and physical resources for effective response.

Due to the recognized economic and social impacts of natural disasters and climate change – perhaps most notably captured in the findings and recommendations of the Sendai Commission – resilience to natural disaster is a growing and prominent concern for infrastructure planners, governments, and citizens.<sup>1</sup> This is particularly true in areas vulnerable to extreme hydrometeorological and geophysical risks, such as floods, earthquakes, and major storms, as well as in areas where rising sea levels or altered weather patterns associated with climate change expose the region to significant vulnerabilities.

Meteorological and geophysical disasters have killed an estimated 1.3 million people between 1998 and 2017, and left an additional 4.4 billion people displaced, injured, or homeless. While fatalities were caused largely by geophysical events, 91% of disasters were caused by hydrometeorological events, including floods, storms, and other extreme weather events. These disasters have resulted in direct economic losses of US$2,908 billion, again largely accounted for by weather-related disasters, which accounted for 77% of total direct losses. Among low-income countries, reported hydrometeorological losses of US$21 billion amounted to an average of 1.8% of the GDP, well above the IMF's 0.5% threshold for a major economic disaster.<sup>2</sup> These impacts push an average 26 million people into poverty every year, overwhelmingly affecting already-vulnerable populations.<sup>3</sup> The World Bank finds that costs are largely under-reported, and that real costs to the global economy amount to an approximate US$520 billion each year.<sup>4</sup> When the costs of medium-intensity but frequent hazards and the slow-onset effects of climate change are further considered in addition to costs associated with high-intensity events (e.g., earthquakes and typhoons), the economic and social impacts are often much higher than otherwise estimated. In the Asia-Pacific region, for example, average annual losses for high-intensity extreme events are US$14.89 billion. These costs rise to an approximate US$19.35 billion when also considering medium-intensity, frequent events, such as heavy rains, and US$27.1 billion if indirect costs are included. Considering the costs of slow-onset events, such as droughts, the average annual costs swell to an astounding US$675 billion.<sup>5</sup>

### Costs of Disruption

The direct and indirect costs associated with disaster-related infrastructure damages are also staggering. Effects on households can be felt through many channels, including delayed health care provision,

> 1 World Bank and PHRD (2012). The Sendai Report – Managing Disaster Risks for a Resilient Future. World Bank, Washington DC.

> 2 CRED and UNISDR (2018). Economic Losses, Poverty & Disasters: 1998—2017.

> 3 The World Bank (2017). Results Brief - Climate Insurance.

> - <u>https://www.worldbank.org/en/results/2017/12/01/climate insurance)disasters</u>

> 4 Ibid.

> 5 UNESCAP (2019). The disaster riskscape across Asia-Pacific: Pathways for resilience, inclusion and empowerment. Asia-Pacific Disaster Report. United Nations Economic and Social Commission for Asia and the Pacific (ESCAP).

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