Developing a Conceptual Framework for Evaluation of Elimination of Visual Pollution Plans, Case of Study: Enghelab Street, Tehran

Visual pollution is one of the problems of urban appearance that great negative influence on the quality of life of citizens. Some elements such as billboards and advertisements on building facades, canals and shafts for air conditioning, electricity and telephone cables, and gas pipes, façade deterioration, heterogeneity of new constructions, disruption of the historical skyline, extensions to balconies and roofs for the increasing usable area of buildings, disruption of the originality of materials due to facade pollution repairs, and furniture disorder including the scattering of lighting elements and lighting are the causes of disorder in urban facades and visual pollution. The purpose of urban rehabilitation projects is to enhance the urbanscapes and reduce visual pollution in urban facades, especially in historical contexts. Also of urban rehabilitation projects create the opportunity for the appearance of the historic city to be a more visible reflection of the historical period that has passed by reducing the disturbances and pollution of the street wall. Although rehabilitation projects have been implemented in some Iranian cities in the last decade, including Tehran, a comprehensive understanding of the issue and the purposes that such projects should pursue has not yet been achieved. Enghelab Street is one of the most important east-west streets of Tehran, which was built during the Pahlavi period. This street is located in the middle of Tehran and since the middle urban fabric of the city is the narrator of a part of the city's history that, if lost, would jeopardize the sequence of the city's story in the future, it is very important to conserve this fabric. Enghelab Street has always played an important role in the political, cultural, and social history of Tehran. The section in front of the University of Tehran, with the gathering of bookstores, has its audience, which has led to the formation of galleries, art stores, book cafes, and socio-cultural exchange spaces. Although all these factors have led to the social and economic prosperity of this part of Enghelab Street, it has also increased visual pollution. Enghelab street rehabilitation & elimination of visual pollution project was presented by the Tehran Beautification Organization in 2015-2016 to preserve historical and cultural values. They wanted to restore authenticity to this street by elimination of visual pollution, improving the facades of buildings, and organizing the billboards and advertisements on building facades. The purpose of this study is to develop the theoretical framework of urban rehabilitation projects based on the historical, identity, physical, perceptual, social, and economic aspects and components of each, and evaluate "Enghelab street rehabilitation & elimination of visual pollution project" in the city of Tehran. It should be noted that the six aspects presented in this article are not completely separate from each other, but have an inseparable interaction. The separation of them in this article is only for the purpose of making it possible to review and evaluate "Enghelab street rehabilitation & elimination of visual pollution project". This study relies on the qualitative approach. This research has two main steps in which a research method was used in each step: The first step is to use content analysis to extract the aspects of urban rehabilitation and develop the theoretical framework of the research by logical reasoning. The second step is analyzing opinions and impressions of the two groups of business owners and pedestrians and codification of interviews by Strauss and Corbin's qualitative analysis method. Through the results of the field study and interviews, the research shows that this project is more successful in "perceptual" and then "physical" aspects than other aspects based on the residents’ perspective. "Increasing legibility", "establishing visual order", and "reducing visual and light pollution" are the most important of its effects, respectively. But in the "social" aspect, especially the interaction with the business owners is less successful. The results of this study show that it is necessary to consider the six aspects of historical, identity, physical, perceptual, social, and economic aspects in urban rehabilitation project. This study also reveals that sometimes a low level of public awareness of the historical and identity aspects of the city can lead to a conflict between citizens' views and the purposes of urban planning in the field of conservation and promotion of historical and identity values. Therefore, in both "historical" and "identity" aspects, cannot rely solely on the residents’ perspective, and the use of the opinion of experts is necessary for these projects. The general agreement of the interviewees to remove all the old billboards of shops of Enghelab street without considering their historical values shows that rehabilitation projects without the use of the opinion of experts can become a threat to values, especially the physical signs of political and social memories, and rust. It should also be noted that future research is proposed to accurately assess the economic impact of this project.