An Empirical Study to Enhance Sustainable Development of The Urban Highway Landscape and Environmental Conditions Based on Greenway Approach and User's Visual Preferences, The Case of Behesht-e-Zahra and Tondgouyan Highways, Southern Tehran, Iran

Urbanization is mostly associated with development of more and more urban areas upon which an extensive network of transportation is necessary to be established. An indispensable consequence of this process is the citizen’s dependency to private cars. There is a growing concern along with urban sprawl which is leading urban management participants to obtain new approaches mostly grounded on the relationship of human ecosystems and natural ecosystems in urban regions. Under circumstances “greenway movement” can be viewed as a new approach to tackle both urban greenery and transportation issues at the same time. It is an approach in which people are more encouraged to use non-motorized vehicles for transportation i.e. to use bikes or even walk to their destinations through a network of greenways facilitated for this purpose. This kind of networks has come into being from 1860 and is widely being established since then. Such a network not only provides inter-city and urban-periphery connections but also provides recreational and ecological functions with unique identity. This paper reviews the literature to provide an analytical framework, then uses site investigation and field observation to collect data related to the site biophysical and cultural resources. A questionnaire survey is also conducted to collect required data for identification and categorization of users’ visual preferences and needs. The collected data are used to synthesize roadside and highway environment master plan, and its related policies and recommendations based on sustainable development objectives. This article used ‘greenway approach’ to analyze Behesht-e-Zahra and Tondgouyan Highways-which are considered as two main urban highways in southern Tehran- for the possible enhancement and improvement on their landscape and environment qualities. The two highways have each the characteristics of a greenway, such as spatial connectivity, linear structure, multifunctional use potential and connecting urban and peri-urban areas. The paper discusses the strategies and action plan to enhance these elements towards creation of a more sustainable greenway network, together with the consideration of aesthetic dimensions, scenic beauty, physical conditions and structural functions of the roadside, based on user’s visual preferences.