Nature and the city : ecohistory and environmental planning in Philadelphia, 1681-2000

Abstract

"Nature" and "the city," as historical and practical ideas, have a complicated relationship in the human mind. In North America, since at least the seventeenth century, enduring contradictions have existed between visions of urban ecology in ideal and crisis terms, as well as between environmentalist and economic objectives. This thesis explores these tensions, tracing the course of ecohistory and environmental planning in the city and region of Philadelphia, Pennsylvania, over more than three centuries and examining current challenges and practices of ecological planning as outgrowths of that history. In establishing his colony in the late seventeenth century, William Penn articulated a vision of a lush city of natural paradise in a region where land values and civic investment would be evenly distributed between town and countryside. However, Penn's plans contrasted with colonial Philadelphia's eventually dense, squalid city of merchants and immigrants, surrounded by country estates belonging to the region's elite families. In the industrial era, similar contradictions are found between interpretations of the city and its machines as beneficent or environmentally destructive forces. Great tensions exist between the city's growth along a rectilinear grid plan and the region's underlying geology. In the twentieth century, zoning and regional plans have aimed to foster "healthy" and balanced ecologies, while rapidly expanding suburbs conceived in a pastoral image have destroyed the "nature" that they attempt to inhabit. The ghettos of the inner city's declining industrial districts, meanwhile, have been plagued by high concentrations of pollution and homes sinking into creeks. Finally, in the later twentieth century, neighborhood and regional planners have confronted the problems of suburban sprawl and decaying ghettos with visions of alternative urban ecologies that are similar to - and sometimes explicitly reference - the plans of William Penn. Challenges and practices of environmental planning in Philadelphia may thus be conceived as parts of a long-term ecohistory of contradictions between environmentalist agendas and forces of economic growth, between visions of natural harmony and crises of environmental depredation.