Stephen Bourne, Atlanta-based project director at Atkins, talks about a new tool which can help cities strengthen their resilience in the face of population growth and the growing impacts of climate change.

Stephen Bourne: Cities across the world, especially those located on our coasts, are fighting what can only be described as a double-edged sword – as populations and economies are growing and placing higher demands on social systems and infrastructure, cities are subject to more extreme natural disasters than ever before. Resilience, in the face of losing power, telecommunications, water, and transportation, is becoming more and more important to sustain our ‘always plugged-in, service-based economy’ needs.

With this is mind, there is a growing desire to find tools that can help cities decide on which measures to adopt to improve their resilience. Over the past few years, I’ve led a team developing a process stakeholders can use to evaluate how resilient their city is now, and how resilient they can make it by adopting new measures in the future. The process is conducted as a workshop, where stakeholders break into teams and use Atkins’ City Simulator tool to develop new city plans and stress-test them over a 40-year time frame to measure the ‘resilience return on investment’. That is, the amount of resilience they will receive for dollar spent on city improvements.

As the name describes, City Simulator is city-wide computer simulation. Based on a City Information Model (CIM), the map-based model captures all utility systems, roads, rail, buildings, lakes, streams; essentially all the physical elements that make up the city. It also integrates agent-based modelling, which means there is a virtual population living, working, commuting, shopping, recreating and relaxing in the model. To capture the return on investment, the model simulates a long time frame, usually 40 years. Over that time frame, sunny days as well as disaster events are simulated.

By simulating this human activity, we can not only understand the negative impacts of extreme events, but we can also measure the positive effects of resilience-measures such as remote working through improving the city’s internet infrastructure. The ultimate value of this approach is that we can capture the interplay of traditional protective infrastructure, like stormwater controls, with new non-emergency focused approaches like teleworking, and thereby measure the total value of any proposed measure. 

The power of this type of tool is not just about the data – stakeholders are a vital part of the scenario testing and planning. It’s a collaborative approach where our experts work together with the stakeholders to develop, test and compare plans, for their cities in workshops.

Our tool has been used in a number of areas that have to plan for extreme weather events. Two key case studies are: a USAID grant project focused on building resilience in coastal cities in the Dominican Republic; and work with the North Carolina Department of Emergency Management focusing on quantifying the return on investment of various proposed projects in response to the impact of the 2016 Hurricane Matthew.

Whilst we can’t be sure when our next extreme natural disaster might arrive, what is certain is that to defend ourselves against the double-edge sword, we need to consider all solutions available to us in the context of resilience.