Suburban sprawl
Urban sprawl (also called suburban sprawl) describes the growth of a metropolitan area, particularly the suburbs, over a large area. In examples of this phenomena, such as Los Angeles, California, new development is often low-density, where the metropolis grows outward instead of 'upward' as with higher densities. Environmentalists and an increasing number of urban planners deplore urban sprawl for several reasons.
In 1990, Atlanta, Georgia was noted in the United States as the city with the largest sprawl area, with 701 mile² (1,815 km²) of urban development. The Atlanta metropolitan area has a population of 3.8 million persons. In contrast, Hong Kong fits a population of 7.3 million persons in 421 mile² (1,090 km²).
Arguments for and against
By many measures, real estate development is taken as a measure of progress. When a city grows laterally, new homes are built, transportation projects are undertaken, and property values often are higher in the new areas of the metropolitan area. In addition, many Americans--especially middle and upper class families--have shown preferences for the suburban lifestyle. Reasons cited include a preference towards lower-density development, better schools, and lower crime rates (even though car-related fatalities often make it more dangerous to live in the suburbs than in the city).
Yet after an explosion of sprawl in the later half of the 20th century in the United States, some drawbacks have emerged towards this growth pattern. When citizens live in a larger space, often at a lower density, car usage often becomes endemic and public transport often becomes infeasible, forcing city planners to build large highway and parking infrastructure. In addition, urban sprawl often consumes land that would other be used for "natural" purposes, such as wildlife reserves, forests, and agriculture. Detractors of sprawl often espouse smart growth and/or New Urbanism. Urban sprawl is not the only way to increase real estate development; many of the cities in Japan, Hong Kong, and Europe which have urban growth plans show larger property value than the suburbs.
Examples in the United States
In the United States, about 2.2 million acres (8,900 km²) of land are added to urban areas. But urban sprawl does not always imply population growth or indicate an influx of immigration. For example, between 1970 to 1990, the population of Detroit, Michigan declined by 8% while its land area increased by 28%. Similar cases include the American cities of Milwaukee, Wisconsin, Pittsburgh, Pennsylvania, New York City, Cleveland, Ohio, and Buffalo, New York. At the same time, the urban cores of these and other major cities experienced the related phenomenon of white flight. However most believe that there exists a correlation between the area of sprawl and population growth.
On the other hand, Portland, Oregon passed laws in 1973 limiting the area the city could occupy--essentially marking the largest possible area of the city and suburbs. After the creation of this boundary, population density increased by 53%. However, the city still sprawled an additional 39 miles (63 km) through the next decade, witnessing a population growth of 146,000. In July of 2004 the city of Portland increased its urban growth boundary to the boundary previously planned for 2040.
See also
