Modeling the impact of walk ability on urban sustainable transportation policies: the case of Mashhad metropolis

Urbanization and the uneven development of urban forms have exacerbated many problems, including reducing the livability of automotive development and walkability. In recent years, paying attention to sustainable transportation and walkability as one of its policies has been addressed by the unfavorable conditions of urban development. Given the long-term effects of policies on land use and their long-term effects on citizens' attitudes and behaviors, choosing the optimal policies and monitoring the effectiveness of planning and policymaking to achieve sustainability seems necessary. In this paper, using the system dynamics model in the Vensim software environment, the urban transportation and its effective factors in Mashhad have been modeled as case studies. Thus, after calibrating and validating the model, the results of 14 indicators in the economic, social, and environmental and transport sectors in 5 scenarios were investigated with the aim of comparing the impact of long-term walkability policy on other sustainable urban transport policies. The results of this study indicate that public and private transport pricing and increased utility of public transport with 28% and 20% improvement in sustainability indicators, respectively. Compared to other scenarios have the highest priority. On the other hand, walking and cycling development policies alone and without connecting to an integrated transport system have less effect on urban sustainability, and sustainable transport planning needs to be done in conjunction with the consideration of walkability and pricing policies.