Prevention is better than a cure. But force majeure and decades of inelegant architectural and societal build-up means not every natural disaster can be mitigated. In these events, engineering plays a vital role in post-disaster solutions. Khai Trung Le reports.
Even with sophisticated analysis and widespread warning systems, natural disasters often have a devastating impact. Within 2018 alone, Japan, Indonesia, the USA, Vietnam, Mexico, Kazakhstan, and Canada, among so many other countries experienced natural disasters with significant death tolls and infrastructure damage. And with the inevitable expectation of further natural disasters in the future, engineering solutions in the aftermath are more important than ever.
However, post-disaster environments bring their own dangers and considerations to the local community, built environment, and economic activity, so beginning restorative work requires carefully balancing all three.
Building back up
When the initial clean-up of natural disasters have been resolved, reconstruction can begin. But while traditional construction is focused on creating new structures that are usually permanent in nature, construction in a post-disaster environment shifts between fluctuating needs, between temporary, transitional, and permanent buildings. Some believe the post-disaster construction environment can provide opportunities. Jim Foucher, Vice President of RBV Contracting, USA, argued that disasters ‘can either provide the opportunity for economic growth in their wake, as with Florida’s Hurricane Andrew in 1992, or economic adversity like with Katrina in New Orleans’.
The post-disaster environment also requires adapting to additional challenges, including debris removal and potential reuse of remaining structures to mitigate logistical challenges, refined priorities and attitudes on a regional decision-making level, and a displaced labour force.
The paper, Post disaster engineering & construction program and project management, published in PM World Today, states, ‘The construction environment is inherently dangerous, and post-disaster uncertainties only exacerbate these concerns’.
Regardless, Foucher continued, ‘Given that construction professionals have the most involvement in the construction of infrastructure, it only makes sense that they should be involved not only when infrastructure is destroyed, but in preventing damage and preparing for disasters’.
Reach for the skies
Early in their development, the potential of unmanned aerial vehicles (UAVs) was eagerly highlighted. Smaller, lightweight, cheaper, and more versatile in disaster areas than planes and helicopters, UAVs have been positioned for aid delivery in perilous or otherwise inaccessible areas, real-time damage assessment, and improving situation awareness through imaging and data acquisition.
In 2017, Peru Flying Labs formed the Mision PIURA consortium in response to the 2017 South America floods to create around 17,300 acres of high-resolution aerial images in three days using nine UAVs. This information was used to support humanitarian agencies in forming a more detailed understanding of the region including infrastructure damage, locating stranded communities and safe areas for resettlement, and efficient routes for aid delivery.
The information collected by Mision PIURA provided the Peruvian Emergency Coordination Center and government ministries with up-to-date information, helping them monitor changes in the water levels of affected areas and direct responders in managing the emergency.
The proliferation of UAVs as a humanitarian technology is propagated by lobbying groups including the British UAV Systems Association and the US Association of Unmanned Vehicle Systems International. However, with their increased use in sensitive post-disaster environments by voluntary, government and law enforcement organisations comes a complicated blurring of fleet responsibility, and the considerations over the use of private and personal data.
Perhaps the least physically present but arguably most transformative means of disaster management and recovery is the use of big data – essentially data sets that are typically too large or complex for traditional data processing. Yun Li, a researcher at the Department of Geography and Geoinformation Science at George Mason University, USA, believes that big data has ‘radically changed the ways through which societies adopt natural disaster management strategies to reduce human suffering and economic losses’.
In the 2018 paper, Big data in natural disaster management: a review, published in Geosciences, Li argues that big data can support the shifting realms of disaster, particularly in monitoring, detection, forecasting and prediction, but also in post-disaster coordination and response, where data come from a disparate array of sources almost twice as large as in monitoring and forecasting. According to Li, while the majority of information is gathered from social media (25%), information from satellites (16%), sensor web and Internet of Things (16%), crowdsourcing (10%), UAVs (9%), simulations (6%), Lidar (6%), spatial data (6%), and mobile GPS (3%) are essential in formulating an effective response.
The paper states, ‘The different sources through which big data is used by entities involved in the assessment of disaster damage need to be effectively coordinated in order to confirm the damage, know of the destruction that may have been left undetected, and prevent the duplication of efforts by responders.’
Big data remains a relatively new tool in post-disaster environments, and while Li is optimistic about its future applications, the paper concludes that more effort needs to be made in ‘further developing research on big data applications in enhancing the efficiency of the public sector’.