A Scenario-Based Impact Evaluation of Rapid Rail Infrastructure Investments on Urban Form and Development in the Greater Dublin Area
Tez Türü: Bütünleşik Doktora
Tezin Yürütüldüğü Kurum: University College Dublin, Architecture, Planning and Environmental Policy, İrlanda
Tez Danışmanı: Brendan Williams, Enda Murphy
Tezin Onay Tarihi: 2012
Tezin Dili: İngilizce
Özet:
The main aim of the study is to examine new Metro North infrastructure provision and its impacts on future land development processes in the Greater Dublin Area (GDA). The Dublin Area has experienced significant population and employment growth starting from the early 1990s. The limited integration of transportation and land-use planning activities has contributed to uncontrolled urban growth, and coming to the early 2000s, sprawl type development has occurred in the peri-urban areas surrounding the existing urban border of the Dublin Region. It is widely accepted that sprawl type development is generally associated with high social, economic and environmental costs. Under this situation, the GDA requires further examination considering future land development processes and new infrastructure provisions within the context of sustainable urban development. This constructs a base for the present study which focuses on economic evaluation of alternative forms of urban development in relationship with the issue of sustainability in new transport provisions within the GDA. The literature on sustainability of transport systems and urban development suggests that there are strong linkages between urban spatial structure and efficient transportation systems. Based on this sustainability considerations, the impact-assessment of newly proposed Metro North project within the GDA is carried out by developing methods of economic appraisal i.e. Cost-Benefit Analysis (CBA) is the selected methodology, and is evaluated based on alternative land development scenarios. Various scenarios are generated by the MOLAND Model applications including: A baseline scenario incorporating a continuation dispersed pattern of urban development and an alternative scenario with rapid rail-oriented corridor development, both presenting the conditions of economic growth. An alternative scenario is also developed for the recessionary development case considering the prolonged recession in the GDA. For the CBA assessment of with rail and baseline scenarios of economic growth and recession, the impacts and indicators specified are: capital costs, public service provision costs, accident costs, vehicle operation costs, system operating cost and revenues, travel time and costs of carbon dioxide emissions and local air pollution. The results obtained from the CBA model show that in the medium-term baseline business-as-usual scenario with no significant development in rapid rail infrastructures is less costly than the with rail scenario resulting in more compact developments along the Metro North catchment area. Nevertheless, it is also concluded that higher benefits of the Metro North investment integrated with a more compact land development policy could be achievable in the longer-term. Another issue is that the scenarios of recessionary development may have different implications in terms of costs and benefits associated with the resultant urban form of such scenarios. Further research is completed in the form of sensitivity analysis to establish if such benefits can still be achieved. The results and findings of the scenario-based CBA model of this study may provide implications for the best future policies and their implementation. Therefore, this study is important in constructing a framework for the future transport policy and planning decisions concerning the GDA.