The Sustainable Development Goals (SDGs) recognise a universal right to basic resources, to water and sanitation, and to safe, resilient, and sustainable cities (Nations, 2015). Achieving these targets requires new ways of responding to urban occupation in contexts marked by extreme wealth disparity and unequal access to infrastructure. The challenge of transforming urban environments is complex – not only does it raise key questions about citizenship and the right to the city, but it also highlights the urgent need for infrastructure that facilitates viable livelihoods for vulnerable inhabitants. In facing future city scenarios, in contexts of growing inequality, it is important for urban and architectural designers to examine systemic frameworks through which cities operate as they grow and perpetuate ingrained systems of infrastructural inequality.

These issues are made stark and legible in the many scars and divisions in urban landscapes in South Africa, the most unequal country in the world (Bank, 2022). For the SDGs to be realised here there needs to be a rapid and substantial shift in how basic services and associated urban infrastructures are conceived and developed, and a re-evaluation of the mechanisms and methods by which people gain access to them. The growing body of research on this topic recognises that urban infrastructure is not simply a set of facile technical devices that control and regulate mechanical, electrical, informational, transportation, and/or other material flows, but rather a systemic network of interfaces that connect (or exclude) people, resources, services, capital and wealth. Thus, urban infrastructures act as assemblages that establish power over, and shape territories of material distribution and equality or inequality [(Dovey, 2012); (Lawhon et al., 2014); (Schnitzler, 2016); (Wafer, 2020)].

Colonial, apartheid, and modern planning practices have entrenched patterns of compartmentalization and systems of resource and labour extraction producing tight strictures of exclusion through which people must operate. South African apartheid-era urban development was implemented with specific intentions of racial segregation. This was achieved via tightly controlled land-use regulations and the rollout of built services and social infrastructures in ways that benefited the white minority [(Schnitzler, 2016); (Mbembe, 2019); (Falling monuments, 2021); (Mpofu-Walsh, 2021)]. Examples of this include regulated provisions for transport, water, electricity, education, work, recreation, and skills development – the legacies of these exclusions are still evident and in cases highly entrenched in the South African landscape. Today, public and private development patterns – both of which follow the dictates of neoliberalism – reinforce unequal urban systems, with built infrastructures continuing to perpetuate poverty and exclusion at multiple scales [(Peres, 2015); (Maharaj, 2020); (Mpofu-Walsh, 2021)].

These historic and unfolding territories of infrastructure operate as adaptive assemblages that interconnect through built environment spaces. From a critical theory paradigm, these spaces are understood as devices that maintain power over and facilitate the territorial marginalization of large majorities of inhabitants (Falling monuments, 2021), particularly in cities of the global south. Conditions of control are partly reinforced by crime responses and more generally by systemic aspirations for exclusive and consumptive urban lifestyles. Formalised urban environments are structured to maximise barriers, surveillance, and private policing while not disrupting the circulation of material market economy consumables. In this respect, capital moves freely through infrastructures of freight warehousing, distribution, and 'lifestyle' offerings often segregated alongside conditions of extreme poverty, infrastructural decay, and violence.

The aim of the study is to identify methods of representation and coding of socio-spatial occupation scenarios that reveal potentialities for the transformation of divisive structures. Material separations between inhabitants of the Tshwane east region are analysed both in terms of characteristics and in terms of potentialities -that is by the relationships that exist between material and human urban assemblages and the opportunities that these relationalities present [(Simone, 2004); (Plessis, 2012); (Landa, 2016)]. Scenarios for the rescripting of infrastructure development strategies are identified through the observational drawing and documentation of existing occupations in marginalised spaces. Challenges are articulated alongside innovative modes of practice in the face of extreme resource scarcity. The reading of urban infrastructure from an adaptive territorial perspective helps us think about alternative modes of material and resource exchange. It demonstrates existing and emergent scenarios at play in our built environments operating through urban junctions at multiple scales over time.

The approach to scale follows the ontological positions set out by (Landa, 2016) – micro-urban form emerges at the individual scale of people and the interactions they share with the material worlds surrounding them. The mezzo scale operates beyond the neighbourhood as regional territories, and in this investigation, the macro scale is set as the whole urban form and its broader territorial network. This multiscale approach enables the visualisation of 'thick descriptions' as identified by (Aswegen, 2021) which provide a qualitative lens through which the mapping processes are developed and articulated. It also helps us think about our infrastructure as both hard and soft, and as complex, adaptive assemblages. From a socio-spatial perspective, formal and informal material worlds are seen to operate through interfaces that can enable or disable dialogue and exchange. The distinction between the formal and the informal is developed after (Dovey, 2012) who acknowledges the complex spectrum that exists between these two terms and recognises that they generally operate in tandem as part of social structures and built environments where the formal and informal operate in a kind of symbiosis. Informal in the context of this paper is used to describe built environments that fall outside of formal building approval processes, that are generally made from the adjoining of Adhoc components and materials to fulfill basic built environment needs or opportunities. It is important to note here, that while the distinction between formal and informal is made in this paper, we recognise more generally the association of the informal building sectors with greater assemblages of other formal and informal processes.

Given the rapid population growth and densification expected in the Tshwane East region alongside historic and perpetuating conditions of urban inequality, it is important to consider the latent potentials at play between formal and informal, and static and kinetic actors within our built environments, to reconfigure existing boundaries of segregation as productive and sustainable sites for human habitation.

Viewed from this perspective we recognise that infrastructure systems function to regulate the flows of materials, resources, people, and ultimately wealth, capital, and power. It is important to note here that the infrastructural means and interfaces by which people are able to communicate and connect, access services, move around, maintain themselves, and generally operate viable livelihoods are often nested within macro systems and devices of political and economic surveillance and/or control. In this respect, they can be understood as operating systems that regulate power and wealth structures. Wafer offers a useful interpretation:

Infrastructures include a complex network of material and institutional structures that underpins the functioning (and dysfunctioning) of modern cities. To the extent that infrastructures are understood as complex networks, they are also therefore implicated into systems of power and politics ... [they] coordinate, connect and distribute people, commodities, capital, and resources. (2020: 86)

Building on this concept, (Easterling, 2021) emphasises the importance of understanding architecture as suspended in thick, lumpy, material mediums and scenarios of operation. A useful distinction to make here is the relationship between ‘hard’ and ‘soft’ infrastructure as described by (Winning, 2010) and (Matsipa, 2017) – that is the physical services (hard elements) that operate through softer human and non-human interfaces and networks. In the same way that software facilitates interactions between components in a computer and hardware represents the electronic fabric of the device, we can think of our cities as a product of both the hard-built environments suspended in and operationalised through softer networks including social norms, customs, laws, relationships, politics, power structures, energy supplies, exchange contracts, etc. By thinking of the spaces that enable or exclude social or exchange arrangements we develop a view to uncover potentialities for recoding segregated worlds. Seen from this perspective we take a reading of space as a principal regulator of urban networks, often nested within territories of surveillance and power. Through the operating potential of space (Easterling, 2016) proposes a ‘hacking’ or infiltrating and subverting of the devices of power that can potentially reconfigure the internal operations of segregated city forms.

Building on the process of lifeworld representation, (Casakin & Valera, 2020) pair occupation patterns with actor networks to understand public space complexity through studies of relationality. The understanding of this relationality means that we can think about designing beyond objects, (Till, 2009) unpacks this by interrogating approaches to design that recognise the interdependencies of materials and making processes and the implications of time and disposition. Part of this argument means that we think about ways in which we adapt and reuse existing built environments, how we inhabit infrastructures and spaces in transformative regenerative ways (Plessis, 2012), and what the worlds we make today will enable in the future. As a means of accessing this, (Frichot, 2019) draws on ideas of gleaning, collecting, gathering, and quilting, (Bhan, 2019) makes an argument for occupying and repairing urban divide and (Mehrotra & Vera, 2018) recognises the synergy between static forms and kinetic actors as socio-spatial change enablers.

The methods and themes identified from the theoretical framework above are used in the contextual analysis to better understand patterns of spatial emergence in highly segregated contexts. The case studies include self-build urban occupations in formally developed areas in Tshwane east. This region makes up the northern portion of the Gauteng province in South Africa and adjoins various other urbanised zones that make up the greater Gauteng city region (GCR) assemblage. As a seat of fiscal and national governance and as part of the largest urban economy in South Africa, the GCR exhibits significant capital investment alongside extreme spatial segregations and inequalities both historic and perpetuating (Ballard, 2021).

The specific case studies focus on two mezzo-scale settlements in Tshwane East (see Figure 1). Case studies 1 and 2 are based in Moreleta Park and explore issues of informality, urban spatial emergence, constructed scarcity, and material assemblages. This area was designated under apartheid for low-density exclusive white occupation with existing black residences displaced. In its present-day Moreleta Park’s development patterns are highly segregated and compartmentalised, with a number of established gated residential and commercial developments alongside informal self-build settlements. The second set of studies are located in Mamelodi and focus on social and recreational infrastructure. Mamelodi was established in 1945 and designated for the resettlement of displaced black persons under apartheid. Both areas exhibit characteristics of informal occupation and self-build adaptations alongside formal infrastructure segregations. The analysis of conditions of segregation and accessibility in these two historically distinct regions allows for a broader sampling of conditions through which infrastructural segregation perpetuates and provides varied insights into ways in which infrastructural interfaces are established, occupied, and potentially transformed.

During the peak of apartheid, a number of displaced black populations were relocated to Mamelodi from the 1950s through to the late 1970s (Breed, 2012). Infrastructure development implemented during the period focused on the construction of housing, the regulation of transportation, and the limitation of access routes to 'white' areas of the city (Strauss, 2019). Here the scarcity of public open space and social infrastructure can be understood as a direct legacy of apartheid planning and as a means to control the gathering potential of non-white groups during the time (Tshwane, 2005). In the post-apartheid period, the housing shortfall in townships has seen a focus on subsidised state housing; the resultant limited focus on non-housing services has led to a lack of maintenance or development of public open spaces and recreation facilities [(Mc Connachie & Shackleton, 2010);(Denoon-Stevens & Ramaila, 2018)]. Where state or NGO-developed social infrastructures have been implemented they often stand as monofunctional giants following the established segregated grain of the region, disconnected from community dynamics. Therefore, as a response, many social infrastructures and services are developed through informal economy sectors and community organisations (Studio, 2020). This spontaneous dynamism often relies on taking inspiration from existing elements (directly linked to services or not) and bringing alterations, additions, different uses, activities, and meanings to objects and spaces to satisfy communal needs (Demba, 2021).

Case study 3 builds on the theme of kinetic potential (see Figure 6) and illustrates on an interpersonal scale, the socio-spatial scenarios and networks observed along a stormwater and access servitude in Mamelodi. Here (Demba, 2021) examines the accessibility of social infrastructure as well as methods by which people build alternative socio-spatial networks, nodes, and routes to facilitate the operations of their daily lives. These ad hoc inventive means are developed through informal economies, and community organisations (Beer, 2020). Examples of social and recreational activities are observed as part of informal infrastructures of trade, gathering, playing, maintaining, exercising, etc., spatial material interventions are adaptive and straightforward in fulfilling needs and are developed through social practice. The occurrence of these activities along a stormwater channel can be attributed to the open space that it maintains which makes it a viable movement route. An important observation in this respect is the common space that these various activities share, this is part of the reason that recreational spaces are considered as they pair human practices with human needs to foster hybrid scenarios catering to social needs. Here, one can draw comparisons to the above scenarios in Moreleta Park where formal infrastructures are considered static elements while the informal and community-based activities represent the kinetic part of the township; where the varied collective actions, patterns of occupation, and the links established between them create systems capable of participating in the sustainable development of future urban schemes if understood correctly and contextually (Demba, 2021) (Katranas, 2021) (Kriek, 2021).

Just as (Pieterse, 2009) after (Simone, 2004) considers the important role that people play in providing infrastructure as collectives to benefit communities in developing contexts of cities of the global south, the study of everyday street interfaces and occupations aims to find ground-up solutions capable of reconciling and reintegrating isolated or underused infrastructures. By recognising all the many human and non-human actors that make up the public realm as an assemblage, we establish new meanings and opportunities for the rescripting of divided spaces.

Through a process of life-world observations of urban occupations, the case studies attempt to reveal systems of socio-spatial networks and assess their operating potential in relation to infrastructural exclusions and needs. The case studies present a broad sample of ways in which urban infrastructures emerge through socio-spatial arrangements in Tshwane east -often operating to circumvent conditions of extreme inequality, scarcity, and exclusion.

Of particular interest is the observation of the concurrent evolution of informal self-build settlements alongside gated communities. Here conditions of territorialisation are seen to agglomerate around capital investment zones and projects. Both formal and informal built environments coevolve through processes of fortification, exclusions, and compartmental occupation. The relationality between occupants of informal economies and those of more formal areas is seen to overlap in many instances, people living in one sector may find themselves working or operating in another. In line with this idea, the contextual analysis reveals the inevitability of the coexistence of formal and informal residential settlements and economies in the region. Through a study of patterns of the assemblage of self-build settlements, the case study also reveals socio-economic relationality -an example of this is the emergence of settlements in congruity with building construction sites as a result of job opportunities. An important question that arises here is what role the funders of capital investment infrastructure projects play in the transformation or perpetuation of conditions of major urban inequality. Built environment projects are always a product of a collaboration between designers, builders, makers, and other stakeholders, and they always operate through relational flows within their contexts. By recognising and affirming these collaborations and partnerships we can potentially transform the way we make our worlds. In facing the urgent need to redress issues of urban inequality it is imperative that built environment practitioners explore scenarios for the establishment of shared access to basic resources and acknowledge the inevitable coexistence of the static and kinetic, and the formal and informal forces that shape our cities.

By illustrating spatial settlement practices alongside divisive urban infrastructures the project identifies key occurrences in Tshwane that are attempting a repair and recalibration of divisive infrastructure. South Africa's urban fabric is constituted of vast networks of civil systems, stormwater services, roadways, parks, servitudes, railways and other publicly owned property. By examining scenarios that challenge infrastructural exclusion this project identifies and tests opportunities for reconceptualising urban forms to reimagine them as shared common elements that have multiple sides and potential functions that can connect rather than divide. The future development of Tshwane and possibly other regions of Gauteng can evolve by fully revealing, representing, analysing, and understanding the variables and relationships that make up the public realm.