THE INTERSTITIAL SPACES OF URBAN SPRAWL: THE PLANNING PROBLEMS AND PROSPECTS – THE CASE OF SANTIAGO DE CHILE By Cristian Alejandro Silva Lovera Submitted in accordance to the requirements for the degree of Doctor of Philosophy in Urban Studies University College London The Bartlett School of Planning September 2016 1 I, Cristian Alejandro Silva Lovera, confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. 2 ABSTRACT Urban sprawl has been largely discussed as a multifaceted phenomenon mainly driven by the housing debate. Nevertheless, this debate has been strongly determined by the focus on the ‘built-up realm’ leaving aside a crucial less addressed dimension defined by the wide spectrum of undeveloped (or less developed) lands and open tracts. Indeed, these lands determine the fragmented and disperse character of sprawl, and define a parallel unbuilt geography. Pieces of countryside, farmlands, landfills, brownfields, geographical accidents, speculative lands, infrastructural areas, military facilities, buffers of security and others appear as different but nevertheless as interstitial spaces – not clearly considered as ‘urban’ – that take part in suburban transformations. Thus, the emergence of these interstitial spaces deserves a closer inspection in order to unveil their origins, role and implications in planning, and to improve the comprehension of urban sprawl and its unbuilt geography. In this vein, this thesis inspects three research questions. First, what are the interstitial spaces of urban sprawl? Second, how they emerge and participate in suburban transformations? and finally, what are their implications in planning? To answer these questions, the thesis develops the concept of ‘interstitial space’ based on a critical revision of current literature, and focused on the different interpretations of institutional actors, their relational character, impacts at different scales and implications in planning. To do so, the capital city of Chile, Santiago, is used as a context of study. Here, various interstitial spaces are analysed using a mixed methodological approach that implies secondary research, fieldwork that involved 56 semi-structured interviews, site visits, revision of representative documentation and data analysis. Evidence found suggests that interstitial spaces are active components of suburban transformations; they emerge as contested spaces and imply major revisions in planning policies aimed to accommodate population and employment growth. 3 ACKNOWLEDGEMENTS I wish to thank to my family, particularly to my wife Marcela for her personal support and patience. This work is dedicated to her with all my love and loyalty. I am also very grateful to my supervisor – Professor Nicholas Phelps – for his guidance, criterion, personal and intellectual support. He trusted me, on my commitment and has promoted my career beyond this process. I would also like to acknowledge to my secondary supervisor – Sonia Arbaci – for her advice, especifically at the early and final stages of this research. 4 CONTENTS 1. INTRODUCTION 1.1. INTRODUCTION ............................................................................. 12 1.2. Background and problem statement .................................................. 13 1.3. THE UNBUILT GEOGRAPHY OF SPRAWL AND ITS ELEMENTS ...................................................................................... 15 1.3.1. Defining the unbuilt geography of urban sprawl .......................... 16 1.3.2. The emergence of the term interstitiality ...................................... 17 1.3.3. The institutional actors determining interstitiality ....................... 17 1.3.4. The different scales of interstitiality ............................................. 18 1.3.5. The relational character of interstitiality ...................................... 18 1.4. PURPOSE AND OBJECTIVES OF THE RESEARCH .................. 19 1.5. METHODOLOGY ............................................................................ 20 1.6. SANTIAGO DE CHILE AS CONTEXT OF STUDY ..................... 21 1.7. Selected interstitial spaces ................................................................. 22 1.8. STRUCTURE OF THE THESIS ...................................................... 22 1.9. KEY FINDINGS AND CONTRIBUTIONS .................................... 24 2. THE UNBUILT GEOGRAPHY OF URBAN SPRAWL 2.1. INTRODUCTION ............................................................................. 25 2.2. THE SPRAWL DEBATE AND ITS ABSENCES .......................... 26 2.2.1. Traditional sprawl and new trends ............................................... 26 2.2.2. New elements in suburbanisation ................................................ 29 2.3. THE UNBUILT GEOGRAPHY OF URBAN SPRAWL ................. 32 2.4. THE SCOPE OF THE UNBUILT GEOGRAPHY ........................... 33 2.4.1. The urbanised countryside ............................................................ 34 2.4.2. Inner suburban lands and their ecological contents ...................... 36 2.4.3. Contiguous expansion .................................................................. 39 5 2.5. THE NATURE OF THE UNBUILT GEPGRAPHY ....................... 41 2.5.1. Determinants of the unbuilt geography ........................................ 42 2.5.2. Categories of undeveloped lands .................................................. 46 2.5.3. Natural and intervened undeveloped lands ................................... 50 2.5.4. The relevance of undeveloped lands of sprawl ............................ 52 2.6. CONCLUSIONS ............................................................................... 58 3. INTERSTITIAL SPACES: TOWARDS A FRAMEWORK FOR ANALYSING THE UNBUILT LANDS OF URBAN SPRAWL 3.1. INTRODUCTION ............................................................................. 59 3.2. BEYOND UNDEVELOPED LANDS .............................................. 59 3.2.1. Critical antecedents to define the ‘interstitial space’ .................... 60 3.3. DEFINING THE ‘INTERSTITIAL SPACE’ ................................... 71 3.3.1. Critical connotations for the ‘interstitial space’ ........................... 72 3.3.2. The meaning of ‘interstitial’ ......................................................... 77 3.3.3. The ‘interstitial territory’ and the ‘interstitial spaces’ .................. 79 3.4. THE SCALES OF INTERSTITIALITY ........................................... 81 3.4.1. Fixing the scale of analysis ........................................................... 85 3.5. THE RELATIONAL CHARACTER OF THE INTERSTICES ....... 86 3.5.1. Spatial aspects of relationality ...................................................... 87 3.5.2. Functional aspects of relationality ................................................ 88 3.6. CONCLUSIONS ............................................................................... 89 4. METHODOLOGY 4.1. INTRODUCTION ............................................................................. 91 4.2. THE CASE STUDY APPROACH ................................................... 92 4.2.1. The context of study ..................................................................... 93 4.2.2. The interstitial spaces of Santiago’s sprawl ................................. 96 4.3. METHODS ........................................................................................ 98 4.3.1. Documents review ........................................................................ 99 4.3.2. Fieldwork ...................................................................................... 99 4.3.3. Data collection ............................................................................ 106 4.3.4. Data analysis ............................................................................... 108 4.4. CONCLUSIONS ............................................................................. 108 6 5. THE ORIGINS AND DETERMINANTS OF SANTIAGO’S SPRAWL AND ITS UNBUILT GEOGRAPHY 5.1. INTRODUCTION ........................................................................... 111 5.2. DETERMINANTS OF SANTIAGO’S SPRAWL ......................... 111 5.2.1. Critical factors of Santiago's expansion ..................................... 112 5.3. DETERMINANTS OF SANTIAGO’S INTERSTICES ................. 134 5.3.1. Critical factors of Santiago’s interstices ..................................... 136 5.4. CONCLUSIONS ............................................................................. 157 6. THE DIFFERENT UNDERSTANDINGS, SCALE AND RELATIONALITY OF SANTIAGO’S INTERSTITIAL SPACES 6.1. INTRODUCTION ........................................................................... 159 6.2. UNDERSTANDING SANTIAGO’S INTERSTICES .................... 159 6.2.1. Definitions and meanings of Santiago’s interstices .................... 160 6.2.2. Impacts of Santiago’s interstitial spaces ..................................... 166 6.2.3. Values and potentials of Santiago’s interstices .......................... 171 6.3. RELEVANT INTERSTITIAL SPACES ........................................ 178 6.4. REGIONAL AND METROPOLITAN INTERSTICES ................. 182 6.4.1. Metropolitan interstices and interventions ................................. 182 6.4.2. Regional interstices and interventions ........................................ 186 6.5. RELATIONAL CHARACTER OF SANTIAGO’S INTERSTICES ....... 187 6.5.1. Spatial relational interstices .......................................................