Urban sprawl and interstitial spaces in Santiago de Chile: the role and implications of undeveloped areas and open tracts in processes of urban expansion

Although urban sprawl has been widely discussed, it is still an open agenda in regards of definition, consequences and ideological implications mainly driven by the housing debate. Apart from differences, there is a common view that consider sprawl as a dynamic process of fragmented growth that also illustrates more complex stages of development characterized by social diversity, polycentricity and an incremental functional self-sufficiency which confirms sprawl more as a ‘process’ than a static scattered landscape. All in all, studies in urban sprawl have been traditionally focused on the production of built-up spaces leaving out the presence of a wide spectrum of undeveloped areas and open tracts which have been left inside the expansion such as geographical restrictions, open spaces, brownfields, landfills, farmlands, forest lands, green corridors, public spaces, military facilities, infrastructural lands, buffers of security, power plants, industrial facilities and others that conform a less addressed dimension of sprawl, somehow as random outcomes from the planning system itself and that affect sprawl’s definitions as well implications in planning. Considering the variety of open tracts, differences in their origins and conceptual approaches, we termed these lands as ‘interstitial spaces’ as a way of reinforce its presence as another component of urban sprawl. Interstitial spaces emerge by different reasons being mainly economic – developers and plans allocate new developments on cheaper outer areas, social – people prefer to live near the countryside, and techno-political – regulations and plans include interstitial areas as restrictions