Urban resilience’s dependency on infrastructure
Updated: Jul 8
The basic dictionary definition of a resilient system is one that can absorb a shock, or recover quickly and resume its intended function. This is very concise and clear – we want our systems to function under all conditions. But the definition also explains why we tend to conflate sustainability with resilience. We define the success of “functioning” using sustainable outcomes. As a computer requires both hardware and software to function; the systems that make a city viable require infrastructure (hard) to function and stakeholders (soft) to define what functioning means. How should cities address the commonalities of infrastructure resilience while allowing for unique sustainability outcomes across systems?
The assumptions of infrastructure in urban resilience and sustainable development
Many definitions of a resilient city mention an array of vital services (e.g. health, housing, transit, education, water, emergency services…etc.), but do not emphasize the dependency of these systems on reliable infrastructure.  That is, while each system can be uniquely defined with sustainability outcomes, all systems that make a city viable share a common infrastructure foundation. And despite the importance of reliable infrastructure, cities do not have a comprehensive methodology for addressing existing urban infrastructure in resilience planning. Consider the City of Boston’s 2018 100RC resilience plan.  In the second paragraph of Mayor Martin J. Walsh’s introductory letter, he states: “We are addressing our most serious shocks, such as extreme weather events, and our chronic stresses, such as economic inequality and aging infrastructure.” Despite identifying “aging infrastructure” as a major chronic threat to be addressed, the term is only mentioned one other time (bottom of page 128) in the entire document as a reference to the 311-phone service where citizens can complain about aging infrastructure. 
Resilient (and reliable) infrastructure is also assumed – but not mentioned – in the most commonly referenced definition of sustainable development: “… development that meets the needs of the present without compromising the ability of future generations to meet their own needs.”  By identifying the assumptions and dependencies within this definition, we find where resilience and reliability have a role. The definition implicitly assumes that our infrastructure systems are intact and delivering basic services (needs) to all (equity) under baseline conditions (reliability) and during, or shortly after, hazards (resilience). The physical characteristics of our infrastructure do not, by themselves, determine what “meets the needs” means – stakeholders do.  This assumption of reliable (and resilient) infrastructure in sustainability is also visually represented by the frequently used Venn diagrams of either the “3Ps” (People, Prosperity, and Planet) or the “3Es” (Equity, Economy, and Ecology). Where each “E” or “P” represents multiple interdependent and dependent systems, all dependent on resilient infrastructure.
Urban resilience, sustainability, and dependence on infrastructure
While the Venn diagrams reduce the concept of sustainability into an easy to understand schematic, there is not a similar representation for “urban resilience” that: 1) embodies the city as a “…a massive system of systems…” ; 2) depicts the dependency of all systems on resilient/reliable infrastructure; and 3) provides a methodology as to where a city should begin its path towards resilience. For example, the City Resilience Framework (CRF)  organizes all city systems into four dimensions and 12 goals. So, it does provide a schematic. But the CRF does not address dependency on resilient infrastructure across the four dimensions. For example, the “appropriate land use & planning” indicator (Leadership and Strategy dimension) calls for “integrated and flexible land use and zoning plans that ensure appropriate development of the city.”  Such plans depend upon the availability of reliable infrastructure to support both existing and new levels of development. And, while “Reliability” is a primary focus of the Infrastructure and Environment dimension (e.g. the “flexible infrastructure” indicator), and is also touched on in the Health and Well-being dimension, the CRF does not provide a methodology for analyzing the reliability of existing infrastructure systems, both in the present and in the future given the projected impacts of climate change (resilient). 
Further illustrating how urban resilience is typically conflated with sustainability is the desire of cities to integrate the United Nations Sustainable Development Goals (SDGs) in resilience reporting. To facilitate the aspiration of a sustainable and resilient city, the World Bank released the Urban Sustainability Framework (USF) , in order to “… enable cities to … advance their sustainability and resilience agendas, and in particular to work toward SDG 11—…making cities inclusive, safe, resilient, and sustainable”. Notice the “…resilient, and sustainable” part. One of the key recommendations in the USF is for rapidly urbanizing cities to promote the more efficient use of existing infrastructure. Yet, again, no methodologies are provided for assessing how to best utilize “existing infrastructure”.  Real urban resilience needs a common framework that shows the connections between professional siloes, stakeholders, and the infrastructure as it relates across systems. It takes a very conscious effort for non-engineers to embrace the role of infrastructure (beyond roads and transit) in urban resilience.
Pros and cons of simplifying sustainability and urban resilience
Yet, despite the simplicity of the Venn diagrams, we rarely achieve the intention of the concept of sustainability. I attended (pre-pandemic) a presentation by a well-respected sustainability firm that projected a slide of the 3E Venn diagram while the speaker immediately said that “…of course, the big 3 in sustainability are the environment, energy, and water”. What happened to Equity and Economy? What if social justice was your only view of a sustainable city? While the Venn diagrams are overly simplified, it is a valuable representation that allows stakeholders to at least embrace the depth of complexity that should be involved when labeling something as sustainable.
Similarly, there is a need to simplify how we view urban infrastructure transitions to better conceptualize and differentiate the desired resilient functioning from the sustainable outcomes of urban infrastructure. Using a straw analogy, where the “straw” represents the pipes and wires that distribute the basic services of a viable city (e.g. energy, water, waste…etc.). On one end of the straw is – Supply (dependent on Natural Systems, aka Natural Capital)– where we pour in processed natural resources (e.g. raw water to potable). The straw then distributes the basic services to – End-users (customers) at the other end of the straw for consumption. The straw has no other role other than a conveying function that should be reliable (baseline) and resilient (shocks). The sustainability outcomes occur at either end of the straw based on the choices of stakeholders: Supply transition (environmental degradation; renewables vs fossil fuels; or water reuse vs another dam) and the End-user transition (how much is each customer consuming; distributed with equity, quality, and accessibility). Does the copper wire (i.e. the 'straw') care if the electrons that it conveys are renewable or fossil-fuel based? For more complex systems, like education, we want our schools to have reliable infrastructure (buildings, water, heat) and the outcomes to be sustainable (affordable, accessible, and “quality” as defined by the stakeholders). Green infrastructure, embodied energy, and Flint, MI are topics of another blog. Point being, we want a system’s infrastructure to function reliably and with resilience in order to support sustainable outcomes as determined by stakeholders.
Foundational Infrastructure Framework
This short article is solely intended to start a conversation around the question — where should a city start its path to resilience? While a simple question, there is a need for a schematic that allows each system in a city to evaluate infrastructure dependencies; while showing each system as separate and able to define its own sustainable outcomes. Consider that many people have spent their careers/lives working to reform a single system within a city’s system of systems (whether education, health, emergency services…etc.). What are the commonalities of resilience that can bridge all city systems?
The Foundational Infrastructure Framework (FIF)  was created to be a useful lens for considering the interconnectedness of systems, while not interfering with each system’s ability to define sustainable outcomes. The FIF provides an analogy that there is an inherent order whether building a house or a city — i.e., from foundation -> house -> home. As shown on Figure 1, the “foundational” portion of the model is dependent on Natural Systems and contains seven main infrastructure systems that support Essential Services (House) that allow for Societal Services (Home) to be viable. For example, in Dependent Essential Services, Food Supply and Distribution are physically dependent on Buildings (warehouses), Energy (fuel), Transportation (all forms), and Water to provide for the Health of a city.  Similarly, in Societal Services, the Housing sector requires connections to Energy, Water, Sanitation, Transportation, and Communications. Please note that “critical infrastructure” (as defined by Homeland Security) can exist at any of the three levels in Figure 1, and all systems are equally important for maintaining a viable city.
The FIF does not dictate any sustainable outcomes, or a hierarchy of systems, just the dependency required for urban resilience. For example, using the house analogy, what is more important, the family that makes the house a home, or the foundation? Of course, the societal services make the city livable, but it is the foundation that makes all systems possible.
Achieving sustainable outcomes from a city’s system of systems requires a reliable and resilient infrastructure foundation. But it is important that urban planners and, all system stakeholders, have their own indicators for better reporting and quantifying the relevance of infrastructure for achieving sustainability. While several cities are informational “hubs” that provide data on public and private infrastructure assets within a city, there is not a methodology that guides urban planners from acquiring data towards processing these data into actionable information and knowledge (DIKW pyramid). Actionable next steps include negotiating future franchise agreements with utilities to include provisions for obtaining all relevant geospatial information, as well as the condition of all assets within the urban boundaries. Perhaps urban planners can incorporate and apply new ways of looking at urban infrastructure resilience (RABID). As well as establishing areas of a city that should not be disrupted and quantifying baseline total economic disruption (TED) due to unreliable infrastructure. I realize that there is more than enough on these topics to read in a lifetime, but it is the path that is important to visualize. Per the Taoist saying: “The journey of a thousand miles begins with one step” (Lao Tzu).
 This short article will not provide a literature review. And, “systems” and “services” are interchangeable in this article. Also, “reliable” and “resilient” is explained in further in the article.
 City of Boston, Mayor's Office of Resilience and Racial Equity, 2019. Retrieved from: https://www.boston.gov/sites/default/files/document-file-07-2017/resilient_boston.pdf
 As detailed further in this blog, the term “aging transportation infrastructure” is discussed throughout Boston’s report without the connection to the underlying (or, overhead) infrastructure.
 Gro Brundtland, World Commission on Environment and Development (WCED): Our Common Future”, 1987
 Reiner, M., and Rouse, D. (2017): Dependency model: reliable infrastructure
and the resilient, sustainable, and livable city, Journal of Sustainable and Resilient Infrastructure, DOI:10.1080/23789689.2017.1386041
 Rodin, J. The Resilience Dividend: Being Strong in a World Where Things Go Wrong; Public Affairs; Profile Books: London, UK, 2014; Volume 5, ISBN 1610394704.
 Rockefeller Foundation. City Resilience Framework; Rockefeller Foundation: New York, NY, USA, 2015.
 Wang, X.; Salat, S.; Painter, D. Urban Sustainability Framework (USF): First Edition; World Bank: Washington, DC, USA, 2018.
 Reiner, M., Pelton, R., & Fang, A. (2018). Integrating a City’s Existing Infrastructure Vulnerabilities and Carbon Footprint for Achieving City-Wide Sustainability and Resilience Goals. Urban Science, 2(3), 53. doi: 10.3390/urbansci2030053
 Reiner, M., & McElvaney, L. (2017). Foundational infrastructure framework for city resilience. Sustainable And Resilient Infrastructure, 2(1), 1-7. doi: 10.1080/23789689.2017.1278994
*cover photo obtained by google search from