Urban Green Space: Places Supporting Urban Resilience

Linda Corkery

Introduction

Urban green space encompasses a range of land uses and conditions, including public parks and gardens, nature reserves, streetscapes, squares and plazas, pocket parks, and river and creek corridors. Besides providing the spaces where people play, relax, socialize, and exercise, urban green space supports the social and physical dimensions of human health and well-being and is linked to the concepts of‘place’ and ‘sense of place,’ and so can also be seen as supporting resilience.

Increased density of urban development has emerged from the need to accommodate fast-growing populations, use existing infrastructure more efficiently, and respond to the economics of land development, along with aspiring to achieve greater sustainability. Too often this has been at the expense of ecological systems that support biodiversity and as well as open space for human use. This result is as problematic in developed areas as it is at the outer fringe of the city. The diminishing size — and in many instances, disappearance — of private backyards in suburban development is mirrored by the limited space between and around high-density dwellings in the urban core. As a result, opportunities for city dwellers to have incidental, everyday contact with nature are significantly reduced while urban ecological systems are severely compromised.

The focus on urban resilience has steadily sharpened over the past 10—15 years, as cities and regions around the world face the challenge of responding to the destruction of physical and social systems wrought by natural disasters and poorly managed urban development. Humans and nature co-exist in urban areas through countless interlinked natural and human constructed systems. These systems need to be strong and adaptable when faced with the damage and trauma caused by acute shocks (e.g. earthquakes, hurricanes, flooding, landslides) or by the slower, incremental destruction that accrues with gradual change (e.g. climate change effects, environmental degradation). Strengthening the ability to ‘bounce back’ is the focus of many contemporary urban development and redevelopment strategies, and is a task shared by multiple built environment disciplines and professions.

In this chapter, the notion of urban resilience is linked to social-ecological systems, connecting people (individuals and communities) to specific physical places, and to the natural ecosystems intrinsic to urban green space. The proposition is that providing urban green space is essential to support and enhance resilience in multiple ways, including social, ecological, and economic.

Building resilience into urban systems so they can withstand disruptive change includes modifying urban constructions; reinforcing the natural systems of the city; and supporting the social structures that allow a city’s residents to act, individually and collectively, in anticipation of or in response to sudden disruption. Viewed in this way, connecting resilience to the concept of place provides a useful framework that addresses systems inherent to both people and place. The physical structures that humans build and inhabit (cities, neighborhoods, public buildings, private dwellings, infrastructure), the forces of nature that impact those built environments, and the social systems that humans devise — all are linked to places. Envisioning this multi-layered, multi-scalar system gives planners and designers an expanded platform for arguing how urban green space underpins urban resilience.

What is Resilience?

Porter and Davoudi observe that “resilience thinking, its approaches, vocabulary and metaphors are rapidly becoming part of the planning lexicon... fast replacing sustainability as the buzzword of the moment” (2012: 329). The concept of resilience has evolved over the years, assuming a variety of meanings in various disciplines spanning engineering, ecology, psychology, urban planning, design, and development. The engineering application of the word ‘resilience’ refers to the capacity of a material or structure to literally ‘bounce back’ to its original condition or form after experiencing a distorting impact. ‘Engineering resilience’ is also described as ‘single-state equilibrium’ and is the approach generally linked to disaster management situations, as well as in the fields of psychology and economics (Pendall quoted in Meerow et al. 2016: 43). This interpretation of resilience also persisted in ecology for some time, with ecosystems or individual species within systems viewed as being able to return to being ‘in balance’ following disruptions to their habitats.

In the 1970s, C.S. Holling, an ecologist working in the field of natural resource management, critiqued this perspective of ecosystem equilibrium and proposed the concept of a ‘multiple state’ or ‘ecological equilibrium’: “systems have different stable states and, in the face of a disturbance, may be transformed by tipping from one stability domain to another” (Holling quoted in Meerow et al. 2016: 43). Contemporary understanding of resilience now accepts the notion of a “dynamic non-equilibrium, which suggests that systems undergo constant change and have no stable state” (Pickett et al. quoted in Meerow et al. 2016: 43). This stance is particularly apt when considering complex urban and natural systems that are experiencing constant change to varying degrees, and particularly those facing repeated threats from natural forces (e.g. hurricanes, tornadoes, floods, droughts) superimposed onto the challenges of accommodating rapid population growth.

As an extension of this, Walker and Salt advance the concept of‘resilience thinking,’ which promotes the idea of “embrac(ing)... human and natural systems as complex systems continually adapting through cycles of change” (2006: 10). Their ideas have merged with those of Holling to formulate the concept of social-ecological systems. This breakthrough idea led to understandings of resilience, transformation, and adaptability being applied to social contexts. Pickett et al. (2004) extended this work by applying an ecological understanding of resilience to issues of urban design and planning (in Mulligan et al. 2016: 349), which, in turn, introduced the issues of human well-being, ecological integrity, and social equity to the framework of resilient thinking.

In their comprehensive analysis of the literature, Meerow et al. (2016: 45) discovered varied and inconsistent definitions of resilience. In conclusion, they proposed what they thought to be a more inclusive definition, allowing for flexibility in its interpretation:

Urban resilience refers to the ability of an urban system — and all its constituent socio-ecological and socio-technical networks across temporal and spatial scales — to maintain or rapidly return to desired functions in the face of a disturbance, to adapt to change, and to quickly transform systems that limit current or future adaptive capacity.

This interpretation of resilience presents what Porter and Davoudi (2012: 330) suggest is a way for planning to break out of:

its obsession with order, certainty, and stasis... [and avoid] preparing ‘blueprint’ type strategies for systems that are non-linear, complex and intrinsically dynamic... If after a disturbance or upheaval of some kind, a system transforms into something different, then this is not seen as a failure in resilience terms, but at an inherent possibility with that system.

How then does sustainability compare to resilience? They are similar, but different concepts; both are relevant and important to framing the way we plan and act in determining our collective future. Sustainability has been a dominating concept for over 30 years, since the now-familiar statement from the 1987 Brundtland Report, Our Common Future, defined it as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs” (Dresner 2002: 31). Environmentally sustainable development (ESD) became a guiding principle in many urban development pursuits toward the end of the 20th century. For example, a commitment to applying ESD in all aspects of its planning and delivery was fundamental to Sydney, Australia’s successful bid to host the 2000 Olympic Games. Sustainability remains an important principle and could be regarded as ‘business as usual’ for urban planning and development strategies. “Resilience is a key concept for operationalising sustainability” (Pickett et al. 2014: 143); in other words, the more resilient a system is, the more likely it can be sustainable.

The Kresge Foundation and Island Press’ Urban Resilience Project presents the concept of resilience as a less “environmentally-charged” term (and less associated with a specific political ideology) than the concept of human-caused climate change (Mazur 2015: 5). Thus, they suggest, there is a better prospect of encouraging a conversation with a wide range of audiences when the issue of resilience can be contained in, for example, discussions of participatory disaster planning or anticipating and planning for future extreme heat events. It draws on the language and activity of community and local self-reliance, rather than concentrating on potential threats of natural disasters and climate change (Mazur 2015: 6).

Resilience, then, is not an end goal, and in this regard, it is like sustainability. It is not something that is ever completed; rather, it is a state, a quality, or a condition. As Lister (2016) comments, resilience is measurable and intentional, and it can be increased. For example, with physical resilience, you can measure how much stress a system, or element of a system, can take before it breaks or becomes dysfunctional. But once it is repaired or renewed, it may be possible to demonstrate the increase in the amount of stress that can be withstood the next time a disruption occurs, depending on the similarity of the disruption. This is what Rodin refers to as the “resilience dividend” (2014: 293). Other authors identify this as the transformative dimension of resilience (Bahadur and Tanner 2014; Bousquet et al. 2016).

Supporting Cities to Become More Resilient

The Rockefeller Foundation’s Resilient Cities program commissioned the development of a framework to assist 100 selected cities identify the qualities and characteristics of ‘resilience’ — unique to them — that must be achieved in anticipation of the disruptions that will inevitably come with climate change (Rockefeller Foundation/Arup 2015). There are varying kinds of disruptions that impact existing systems. Acute systemic shocks, such as those associated with political conflict and natural disasters, shake us out of our complacency. Bush fires, floods, landslides, earthquakes, hurricanes, technology changes and/or failures are other frequently occurring events that displace populations and destroy property and natural systems. Equally disruptive are the incremental

chronic stresses that accumulate over time, often undetected, until they are truly problematic (e.g. declines in air and water quality, the cumulative impact of extreme heat events).

Extending the idea that resilience enables the ability to ‘bounce back’ after disruption is the perspective that systems can ‘bounce forward’ (Mazur 2015; Newman et al. 2017). How can individuals, communities, and cities anticipate and plan for the disruptions that will inevitably occur and be not only prepared to withstand them, but also able to emerge and regroup, restore, and even progress? Defining urban resilience as “the capacity of a community to anticipate, plan for, and mitigate the dangers — and seize the opportunities — associated with environmental and social change” (Mazur 2015: 11) refocuses resilience thinking onto future scenarios, rather than anticipating how to return conditions to what they were before an event.

These two versions of resilience — bouncing back and bouncing forward — are also referred to as preventive/proactive and restorative/reactive resilience. Preventive/proactive resilience approaches anticipate future problems and seek to strengthen physical infrastructure, and ecological, social, and economic systems, so they can quickly rebuild and progress. Restorative/reactive modes provide an immediate response to an emergency or acute shock and then focus on managing the recovery and trying to return things to the previous conditions. However, Vale points out: “Proactive/preventive resilience entails upfront expense and difficult choices about which parts of the built environment should receive investment and, therefore, which people should benefit” (2014: 194). This echoes the caution expressed by Meerow et al.: “resilience for whom, what, when, where, and why needs to be carefully considered” (2014: 46).

As one of the Rockefeller Foundation’s 100 Resilient Cities, the City of Sydney, Australia is developing a preventive/proactive approach to increasing its resilience. Its preliminary resilience assessment was presented in 2016. Using the Foundation’s City Resilience Framework and assessment methodology, the initial investigations identified the key potential shocks and stresses facing Sydney. These include terror attack, cyber-attack, digital network failure, a water crisis, financial institution failure, extreme weather, and disease pandemic. Similarly, the major chronic stresses to which the city is vulnerable are deemed to be chronic disease, drug and alcohol abuse, inequity, housing affordability, employment diversity, health services demand, transport diversity, and social cohesion (Resilient Sydney 2016: 13).

Another aspect of the preliminary assessment identifies Sydney’s vulnerable assets as its:

• • health infrastructure (facing increased demand from an aging and growing population)
• • airports (critical economic links)
• • railways (in light of past major network failures)
• • wastewater and stormwater systems (capacity constraints and an aging network risk polluting the city’s waterways)
• • commercial buildings and structures (interdependencies with city systems)
• • communication networks (critical information technology services)
• • energy network (strong interdependency for a reliable supply)
• • water supply (limited diversity and availability during droughts).
• (Resilient Sydney 2016: 13)

It is significant to note that Sydney’s network of urban green spaces is not identified as a ‘vulnerable asset,’ yet these natural features of the urban landscape are acknowledged as delivering critical environmental services. As noted previously, urban green space encompasses a range of land uses and landscape conditions — public parks and botanic gardens, nature reserves, streetscapes, pocket parks, river and creek corridors — and, it can be argued, it is fundamental to building the resilience of individuals and communities and the natural systems of the city. Diverse kinds of green space throughout the metropolitan region provide many ecosystem services on which we depend for

Figure 26.1 Tanner Springs Park, Portland, Oregon, incorporates constructed wetlands for stormwater management and a place of respite in nature for local residents.

Source: Photograph by Linda Corkery.

our health and well-being, but of which we are largely unaware. These essential ecosystem services include returning oxygen to the air we breathe, cooling the air temperature, ameliorating the impacts of the urban heat island effect, intercepting and assisting in the control of storm water runoff, and providing farmland for food production which directly contributes to a region’s economic activity (Tzoulas et al. 2007) (Figure 26.1).

Within the list of chronic stresses identified in the Resilient Sydney analysis are four issues that could be addressed, directly or indirectly, through providing and activating urban green space. Reductions in chronic disease and health services demand can be achieved through access to urban green space, while the same spaces can address social system aspects of inequity and support social cohesion. Urban ecosystems, the ‘green infrastructure’ of the city, are vulnerable assets in the face of continuing urbanization and development. The Resilient Sydney report agrees: “The natural environment and green areas of Sydney are under pressure from development, especially at the edge” (Resilient Sydney 2016: 24). These areas are the key features that can potentially support the resilience of people and natural systems. The challenge is to convince decision makers by providing evidence of the connections between urban green space and increasing urban resilience.

Working within a social-ecological systems framework affords urban planners and designers a perspective on cities as ‘complex adaptive systems.’ “This helps consider the interdependence between communities and the environment — among many other subsystems — in which cultural and social relations play as important a role as do the local ecology and habitat” (Mehmood 2016: 407). Further, it can underpin a convincing argument for the capacity of green space and green infrastructure to enhance urban resilience, linking people — individuals, groups, communities — to specific physical places as well as the ecological systems that are inherent in urban green space. The proposition is that provision of urban green space is essential, for many reasons, and particularly for its capacity to support both social and ecological resilience.