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MPhil in Engineering for Sustainable Development

global challenges, engineering solutions

Overcoming barriers to sustainable transport in U.S. cities – a case study of cycling in Philadelphia

J Ward-Waller

Overcoming barriers to sustainable transport in U.S. cities – a case study of cycling in Philadelphia

Since the creation of the Federal Highway System, the U.S. transport system has been built around travel by private car and has neglected other modes of travel. This system is caught in a downward spiral of unsustainability: more cars fill up the roads each year, more maintenance and investment is required to maintain and expand existing roads, roads are becoming less safe for cyclists and pedestrians who, therefore, also choose to drive. Beyond the costs of maintenance and road congestion, an auto-centred transport system causes a whole spectrum of other negative consequences to society, human health, and urban and natural environments. All these negative impacts have huge cost implications largely ignored by transport decision makers. In contrast, a sustainable transport system provides equal access to all modes for all people using minimal energy, land, and resources without damaging human and environmental health. This translates in the urban context to substituting auto use with efficient alternative modes that are affordable and well connected for all users. Active transport modes – walking and cycling – are the ultimate sustainable modes, providing affordable mobility with near zero environmental impact while benefiting human health. Cycling may provide the best substitute to driving in an urban context because the user can access the same flexibility of routes and destinations at roughly the same speed. The city of Philadelphia at this particular time presents an intriguing opportunity for expanding cycle transport. Many necessary conditions are already in place and a movement toward sustainability is growing. This research identifies major challenges confronting transport policy changes designed to stimulate a modal shift to cycling as a primary transport mode from personal auto use. Philadelphia is used as a case study context. A number of barriers to more transport trips via sustainable modes enable the existing system structure to continue to dominate. Barriers specific to increasing the percentage of trips by bicycle in Philadelphia include car-oriented land use, negative attitudes and perceptions, education shortfalls, inadequate infrastructure and limited right-of-way, inadequate safety and law enforcement, and existing policy and funding structures. Examples from locations as diverse as Bogotá, Colombia; Portland, Oregon; the Netherlands; and New York City illuminate policies and methods that create a positive cycling environment and support a shift in consumer transport choices. Based on analysis of these examples policy recommendations are made to generate a transformation to cycling as a major urban transport mode in Philadelphia and more generally to sustainable transport modes as primary travel modes in U.S. cities. The most effective policies stimulating cycle transport have addressed all the major barriers with a coherent strategy, putting in place strong restrictions on car use as well as provisions for high quality cycle facilities. The recommended policies are developed into a framework used to examine the ongoing efforts in Philadelphia and what new policies are needed. Finally, recommendations are made and conclusions drawn on applying the policy framework to expanded efforts in Philadelphia and to wider sustainable transport initiatives in other U.S. cities.


Course Overview


The need to engage in better problem definition through careful dialogue with all stakeholder groups and a proper recognition of context.


An ability to work with specialists from other disciplines and professional groups acknowledging that technical innovation and business skills also must be understood, nurtured and combined as precursors to the successful implementation of sustainable solutions.


An understanding of mechanisms for managing change in organisations so future engineers are equipped to play a leadership role.


An awareness of a range of assessment frameworks, sustainability metrics and methodologies such as Life Cycle Analysis, Systems Dynamics, Multi-Criteria Decision making and Impact Assessment.