Evidence-based spatial intervention for regeneration of deteriorating urban areas, a case of study from Tehran, Iran

Throughout the urban development process over the last seven decades in Tehran, the capital city of Iran, many self-generated neighbourhoods have developed in which the majority of the residents are low-income families. On one hand, the main spatial attribute of these deprived neighbourhoods is spatial isolation from the surrounding, more affluent areas, which is accompanied by inadequate urban infrastructure and a lack of accessibility and permeability. On the other hand, the Tehran City Revitalisation Organisation - the governmental sector which is in charge of the deprived areas - is incapable of conducting urban regenerations without investment from the private sector, and is seeking methods to create ‘socio-economic stimulant zones’ to attract private sector participation in regeneration programmes. In this regard, this research investigates the notion of ‘spatial isolation’ which in return causes socio-economic isolation as highlighted in the literature. The research suggests that in order to develop feasible regeneration programmes, which can meet the interest of both people and government, and release the deprived area from isolation both spatially and socio-economically, the regeneration plans should focus on public open space developments as ‘socio-economic stimulant zones’. With regard to this idea, the research highlights the street as a ‘social arena’ – not arteries or thoroughfares – as the type of public open space in which its development could not only release the deprived areas from spatial isolation, but could also direct more pedestrian movement to and through the deprived neighbourhoods, making more opportunities for the creation of socio-economic interactions. In this respect, the theory of ‘natural movement’ and theories and literature of ‘integrated public open spaces’ form the theoretical framework of the research to support this idea. For further investigation, two case studies, one as the deprived area and one as the control area, have been chosen, and the spatial pattern of the city and the two cases have been analysed in regard to the notion of ‘spatial isolation’ through Space Syntax using Depthmap software and GIS. Also, the correlation between the distribution pattern of commercial land uses and syntactic measures across the city of Tehran is investigated to identify the potential streets in which to create commercial opportunities. Afterwards, in order to study the street life and the variety of activities the streets can afford, a few locally integrated streets in the deprived case have been chosen. At this stage, nineteen behaviours have been observed and classified in five major classes including the necessary, social, optional, hazardous, and occasional activities, and the correlation with syntactic measures are studied. Moreover, the methods of developing a route filtering system and a transformability index for identifying the most suitable streets for the creation of a pedestrian friendly network are discussed, using an example of a deprived area, integrating it with the surrounding urban fabric to create the ‘socio-economic stimulant zones’. The results show that by identifying the underlying spatial pattern of the urban fabric, it is possible to release the deprived areas from its spatial isolation through developing a street network without causing urban fragmentation. This approach could also form a cost-effective basis for developing a pedestrian friendly street network as one of the ‘socio-economic stimulant zones’, which the Tehran City Revitalisation Organisation is looking for; the type of streets that not only support the necessary activities and transportation, but could also facilitate socio-economic interaction