Moving People: Traffic Congestion, Road Building, and Sustainable Transportation Solutions in Urban Areas, страница 3

This paper addresses the question of whether sustainable solutions to traffic congestion exist and, if so, how they can be applied.  This paper reviews past approaches to urban transportation, researches the present outcomes of those approaches, and studies alternate strategies to urban transportation.  Selected metropolitan areas are assessed to obtain lessons learned on sustainable transportation.  The essay also notes current sustainable transportation strategies available for implementation on broad levels; improving public transportation and transport options, using innovative land use strategies, reducing private vehicle use and vehicle emissions, increasing taxation, researching new technologies, and integrating these and other approaches are some mitigating strategies that can help regions move away from unsustainable road building and subsequent congestion.  

The result of this research is a proposed sustainable urban transportation framework and an example pilot project that may be useful to transportation agencies in both developed and developing nations.  While one sustainable transportation solution set may not be transferable to diverse cities across the globe, it is possible to use a framework that can be applied, wholly or in part, across large regions.

2.  Sustainability in Transportation

2.1  Definitions

Sustainable development has been defined as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs” (World Commission on Environment and Development, 1987).  This definition indicates that present generations must strategically manage resource consumption while considering current and future needs.  

Similarly, the world’s carrying capacity is defined as the “maximum load that can safely be imposed on the environment by people” and a diminished carrying capacity “may soon become the single most important issue confronting humanity” (Rees, 1996).  The load imposed on the environment includes an increasing per capita consumption in both developed and developing nations; evidence suggests that this load already exceeds the carrying capacity upon which humans depend (Rees, 1996).  Presently, the debate on whether this trend toward excess may be halted or reversed continues.

Ongoing discussions about the sustainable movement of people and goods are a necessity, considering this limited carrying capacity.  This is particularly true in many developing countries where populations are flourishing at exceptional rates.  Recent data suggest that half the world’s population resides in urban areas (United Nations Environment Programme, 2000).  There is a challenge in urban transportation to provide for the traveling needs of city inhabitants and visitors without compromising the ability to meet the (ecological and transportation) needs of future populations.  

Simply stated, traffic is the movement of people and goods, while congestion occurs when traffic volumes exceed roadway capacities.  Various technical metrics have been developed to help track congestion.  For example, some researchers developed a density measurement that examines traffic volume (i.e., demand) and the number of major roadway lanes (i.e., supply) in a region (TTI, 2005).  If carrying capacity is the maximum load that can be imposed, then increased traffic volumes diverge from sustainability because the carrying capacity is surpassed.  

Sustainable transportation may be defined as transport of people and goods where: 

•  “the majority of citizens should be able to conveniently meet most of their local needs by foot, cycle and public transport, 

•  public transport services sufficient to meet these needs are available and affordable, 

•  longer distance journeys between urban centers are adequately served by public transport, 

•  those journeys which go by private transport, pay their full economic and environmental costs, and