Linkages Between Transportation Planning and the Environment

摘要

Transportation investments have in the past been among society's most important contributors to environmental improvement, but today transportation programs and projects are more often of concern as sources of major environmental problems. Over the past 30 years, since the enactment of the National Environmental Protection Act (NEPA) and the first Clean Air Act amendments, the relationship between transportation planning and environmental policy making has continuously become more complex and problematic. Until about 1835, when early public transport was just being introduced into many cities, virtually everyone resided within walking distance of where he or she worked, whether on a family farm or in an urban area. The limited capacities of transportation systems determined that most people traveled very little and experienced tightly bounded environments. By the beginning of the 20th century, transportation had evolved rapidly from horse carts to horse-drawn omnibuses to street railways, and cities expanded dramatically in response to increasing mobility. But cities were still mostly crowded, dirty, dense, congested places, beset by a myriad of environmental problems and limited in size by their transportation systems. The first national conference on city planning and the problems of congestion was held in Washington, D.C., in 1909. The conference was characterized by many speeches in which intellectuals of the day insisted that the environmental challenges of their time-the disease, poverty, darkness, and vice of the North American city-were caused by the scourge of high-density living and that it was the job of urban transportation planners to build public transit routes to outlying areas for the explicit purpose of lowering density and improving living conditions. Mary Kingsbury Simkhovich, for example, the only woman to address the first annual conference on city planning, urged that new immigrants to New York City should be whisked to low-density suburbs before they had a chance to settle in lower Manhattan and be destroyed by the urban densities, vices, and diseases induced by squalid urban environments. Subways to new outlying communities were urged, combined with low flat fares, so that low-income people could afford to live at low density at the edge to benefit from environmental improvement and to avoid the pitfalls of inner-city living. The transportation system was the key to environmental betterment. The relationship between transportation and the environment at this time was an intimate one, as it is now, but there was greater emphasis on policy discussions about transportation as a provider of environmental benefits instead of a source of environmental pollutants.