Green infrastructure and informal settlements: rapidly growing metropolitan areas in search for a sustainable solution

Twenty per cent of the world's urban population lives in inadequate housing, more than half of which live informal settlements. These residents often experience a low quality of life and face multiple environmental challenges. Due to unplanned construction and rapid development, informal settlements are frequently exposed to the consequences of environmental risks, such as air pollution, flooding, and drought. High-level international policy documents urge a need for innovative solutions to upgrade informal settlements in a more sustainable way to reduce the existing inequalities.
An extensive bank of academic literature substantiates the potential of enhancing green infrastructure provision as an effective approach to manage environmental risks. Yet despite this wealth of research, green infrastructure is often overlooked as an academic focus in the analysis of development issues in informal settlements. This thesis seeks to redress this knowledge deficit by examining the in/significance and potential of green infrastructure in informal settlements. To do so, this thesis examines two informal settlements in the Tehran Metropolitan Area, an area which due to rapid development is facing multiple environmental issues such as air pollution and the degradation of green areas. The research involves qualitative documentary analysis, the analysis of 64 semi-structured interviews with multiple planning actors, and the interpretation of data collected from field observations. Employing the theory of ‘conflicting rationalities’ devised in the global South as a framework for analysing multiple contending rationalities regarding green infrastructure in informal settlements, the thesis provides several original contributions to knowledge. First, it identifies the impact of multiple rationalities in framing the invisibility of informal settlements in planning policy and development activity. Second, it determines the centrality of green infrastructure in this framing process. Thirdly, it distinguishes the role played by greening projects in generating and exacerbating inequalities between informal settlements and wider urban environments. Finally, the thesis provides insight into the problems emerging from financial opportunities resulting from the planning of green areas to reveal the complexity of social and political dynamics in an understudied context. Therefore, it problematises the uncritical advocacy of green infrastructure for meeting the urban development challenges experienced in the global South.