Flooding: How can cities be prepared for an increasingly unpredictable future?

2018 was a year of unprecedented global weather events. In Asia, Super Typhoon Mangkhut brought close to $50 billion in damages to Hong Kong and China, on top of $16 to $20 billion it exacted from the Philippines (Yap et al., 2018), while extreme precipitation-induced flooding in Kerala state killed at least 350 people and displaced over 800,000 (Kotecki, P., 2018). Meanwhile, 2019 started off with a historic deep freeze in the United States, brought about by unusual polar vortex formation (Channel News Asia, 2019).

Causes of climate change has long been associated with extreme events and is the biggest threat to the planet as reported by the World Economic Forum. Unless drastic changes are made to prevent global temperatures from rising more than 1.5 degrees Celsius, it is likely that we will continue to witness such events with increased magnitude and frequency. These events will continue to interact with complex systems, eventually set off their own ripple effects in a cascading manner akin to toppling dominoes (U.S. Global Change Research Program, 2018).

Introducing Resiliency in Global Warming

In the face of global climate change and diminishing natural resources, designing today’s cities and buildings require environmental, economic, and social considerations. The Rio Earth Summit in 1992 saw Sustainability at the forefront of many global policies aiming to minimize impacts on the environment. While Sustainability focuses on how we can slow down effects of global warming to the Earth, there is also a pressing need to look into the aftermath of warming – that has long been associated with extreme weather events. This is where we enter a new field known as “Resiliency”.

Importance of Resiliency Planning

For the past 20 years, climate-related calamities accounted for 91% of all disasters, with floods topping the list at 43%. Direct economic losses within this period due to climate-related and flooding specific disasters brought about US$2,245 billion and US$656 billion worth of damage respectively (Crunch, C., 2018). In terms of property value, a study by First Street Foundation (2019) has found that property values on the East and Gulf coasts of United States have reduced by $16 billion due to flooding threats, signalling that the market is already reacting to such disasters. Recent research in the field of attribution studies has further demonstrated that the frequency, intensity, and duration of natural disasters will continue to increase due to climate change (Achakulwisut, P., 2019).

And how do all these impact our lives and homes? How will our cities deal with such uncertainties of the future? Are we doing enough to overcome the challenges that lie ahead while mitigating risks? – The field of “Resiliency” attempts to shed light on planning ahead for such possible uncertainties of the future. From a broader perspective, resiliency is defined by the capacity of individuals, communities, institutions, businesses, and systems within a city to survive, adapt, and grow regardless of the kinds of chronic stresses and acute shocks they experience (100 Resilient Cities, 2019). From a flooding perspective, it is about how cities can plan for a flood-resilient future.

In light of recent severe events, and the risk of them occurring again, it is appropriate to consider how to assess flood risks in order to reduce the likelihood of flooding, and robust planning for a flood-resilient future. Such an approach usually considers the 4-R model developed by the Multidisciplinary Center for Earthquake Engineering Research (MCEER) at the University of Buffalo in the United States, which describes resilient systems as one that encompasses the following properties:

  1. Robustness (ability to withstand shocks, such as housing and bridges built to withstand flood waters)
  2. Redundancy (functional diversity, such as multiple evacuation routes)
  3. Resourcefulness (ability to mobilize when threatened, such as functional community groups who can quickly turn a community centre into a flood shelter), and
  4. Rapidity (ability to contain losses and recover in a timely manner, such as access to quick finance for recovery)

Digitisation Enables Us to Predict Flood Risks Unlike Before

The World Economic Forum 2019 in Davos with Industrialization 4.0 taking centre stage focused on digitisation, which enabled the interaction of multiple layers of data to generate insights and predictions unlike before. Such approach towards flood resiliency will transcend current approaches, which are currently conducted in a siloed, non-repeatable, and non-integrated fashion, as well as address currently missing key considerations, from specific geographies to the timing of storms that introduces complex compound flooding (Begos, K., 2019).

Our approach leverages on a common Geographic Information System (GIS) platform that brings together a multitude of data accurately geo-referenced to a single point, providing the basis that makes interaction possible. Among the comprehensive list of data required (refer to Illustration A) for such an analysis are the topographical survey, building models, local rainfall, waterbody distribution, drainage network, and imperviousness data, that are most crucial for an accurate assessment.

Read the full article here at Perspectives, Surbana Jurong’s thought leadership platform.

Comments are closed.

Our Member Companies


About the SJ Connects e-newsletter: SJ Connects is published monthly by the Surbana Jurong Group, a global urban, infrastructure and managed services consulting firm, with over 70 years of track record in successful project delivery. Headquartered in Singapore, the group has a global talent pool of 16,000 across Surbana Jurong and our member companies AETOS, Atelier Ten, B+H, KTP, Prostruct, RBG, SAA, Sino-Sun and SMEC, based in over 40 countries. We provide a full suite of multidisciplinary consultancy services across aviation, healthcare, hospitality, transport, water and environment as well as energy and resources. Our technical teams include architects, designers, planners, engineers and other specialists driven by progressive thinking and creative ideas in our mission of “Building Cities, Shaping Lives”.