Urban sprawl, also known as suburban sprawl, is the spreading of a city and its suburbs over rural land at the fringe of an urban area. Residents of sprawling neighborhoods tend to live in single-family homes and commute by automobile to work. Low population density is an indicator of sprawl. Urban planners emphasize the qualitative aspects of sprawl such as the lack of transportation options and pedestrian friendly neighborhoods. Conservationists tend to focus on the actual amount of land that has been urbanized by sprawl.
The term urban sprawl generally has negative connotations due to the health and environmental issues that sprawl creates. Residents of sprawling neighborhoods tend to emit more pollution per person and suffer more traffic fatalities. Sprawl is controversial, with supporters claiming that consumers prefer lower density neighborhoods and that sprawl does not necessarily increase traffic. Sprawl is also linked with increased obesity since walking and bicycling are not viable commuting options. Sprawl negatively impacts land and water quantity and quality and may be linked to a decline in social capital.
In Utah, which has been one of the top ten fastest growing U.S. states since at least 1990, Jordan Landing has become a byword for suburban sprawl. In response to the rapid population growth of the southern Salt Lake County area, a ten-lane freeway, the Mountain View Corridor, a light rail line, UTA TRAX, and a double-decker commuter train, FrontRunner, are being built to facilitate efficient transportation.
Sprawl is characterized by several land use patterns which usually occur in unison:
This refers to a situation where commercial, residential, and industrial areas are separated from one another. Consequently, large tracts of land are devoted to a single use and are segregated from one another by open space, infrastructure, or other barriers. As a result, the places where people live, work, shop, and recreate are far from one another, usually to the extent that walking is not practical, so all these activities generally require an automobile (though a bicycle may also be feasible).
Low-density land use
Sprawl consumes much more land than traditional urban developments because new developments are of low density. The exact definition of "low density" is arguable, but a common example is that of single family homes, as opposed to apartments. Buildings usually have fewer stories and are spaced farther apart, separated by lawns, landscaping, roads or parking lots. Lot sizes are larger, and because more automobiles are used much more land is designated for parking. The impact of low density development in many communities is that developed or "urbanized" land is increasing at a faster rate than the population.
Another kind of low-density development is sometimes called leap-frog development. This term refers to the relationship, or lack thereof, between one subdivision and the next. Such developments are typically separated by large green belts, ie tracts of undeveloped land, resulting in an average density far lower even than the low density described in the previous paragraph. This is a 20th and 21st century phenomenon generated by the current custom of requiring a developer to provide subdivision infrastructure as a condition of development (DeGrove and Turner, 1991). Usually, the developer is required to set aside a certain percentage of the developed land for public use, including roads, parks and schools. In the past, when a local government built all the streets in a given location, the town could expand without interruption and with a coherent circulation system, because it had condemnation power. Private developers generally do not have such power (although they can sometimes find local governments willing to help), and often choose to develop on the tracts that happen to be for sale at the time they want to build, rather than pay extra or wait for a more appropriate location.
Areas of urban sprawl are also characterized as highly dependent on automobiles for transportation, a condition known as automobile dependency. Most activities, such as shopping and commuting to work, require the use of a car as a result of both the area's isolation from the city and the isolation the area's residential zones have from its industrial and commercial zones. Walking and other methods of transit are not practical; therefore, many of these areas have few or no sidewalks. In many suburban communities, even stores and activities that are close by are contrived to be much further, by separating uses with fences, walls, and drainage ditches.
Developments characteristic of sprawl
Housing subdivisions are large tracts of land consisting entirely of newly-built residences. Duany and Plater-Zyberk claim that housing subdivisions “are sometimes called villages, towns, and neighborhoods by their developers, which is misleading since those terms denote places which are not exclusively residential.” They are also referred to as developments.
Subdivisions often incorporate curved roads and cul-de-sac. Such subdivisions may offer only a few places to enter and exit the development, causing traffic to use high volume collector streets. All trips, no matter how short, must enter the collector road in a suburban system. (Duany Plater-Zyberk 5, 34)
Shopping centers are locations consisting of retail space. In the U.S. and Canada, suburban context these vary from strip malls which refer to collections of buildings sharing a common parking lot, usually built on a high-capacity roadway with commercial functions (i.e., a "strip"). Similar developments in the UK are called Retail Parks. Strip malls/retail parks contain a wide variety of retail and non-retail functions that also cater to daily use (e.g. video rental, takeout food, laundry services, hairdresser). Strip malls consisting mostly of big box stores or category killers are sometimes called "power centers" (U.S.). These developments tend to be low-density; the buildings are single-story and there is ample space for parking and access for delivery vehicles. This character is reflected in the spacious landscaping of the parking lots and walkways and clear signage of the retail establishments. Some strip malls are undergoing a transformation into Lifestyle centers; entailing investments in common areas and facilities (plazas, cafes) and shifting tenancy from daily goods to recreational shopping. European countries such as France, Belgium and Germany have implemented size restrictions for superstores found in strip malls in an effort to limit sprawl (Davies 1995).
Another prominent form of retail development in areas characterized by "sprawl" is the shopping mall. Unlike the strip mall, this is usually composed of a single building surrounded by a parking lot which contains multiple shops, usually "anchored" by one or more department stores (Gruen and Smith 1960). The function and size is also distinct from the strip mall. The focus is almost exclusively on recreational shopping rather than daily goods. Shopping malls also tend to serve a wider (regional) public and require higher-order infrastructure such as highway access and can have floorspaces in excess of a million square feet (ca. 100,000 m²). Until recently, the largest shopping mall in the world was the West Edmonton Mall, while the largest in the United States is the Mall of America. Now, several larger ones have been built and/or are planned in China. Shopping malls are often detrimental to downtown shopping centers of nearby cities since the shopping malls acts as a surrogate for the city center (Crawford 1992). Some downtowns have responded to this challenge by building shopping centers of their own (Frieden and Sagelyn 1989; consider also Toronto Eaton Centre (1977), Ottawa's Rideau Centre, Boston's Shops at Prudential Center, and Providence's Providence Place).
In the 1970s, the Ontario government created the Ontario Downtown Renewal Programme, which helped finance the building of several downtown malls across Ontario (such as Eaton Centre). The program was created to reverse the tide of small business leaving downtowns for larger sites surrounding the city.
Fast food chains
Fast food chains are common in suburban areas. They are often built early in areas with low property values where the population is about to boom and where large traffic is predicted, and set a precedent for future development. Eric Schlosser, in his book Fast Food Nation, argues that fast food chains accelerate suburban sprawl and help set its tone with their expansive parking lots, flashy signs, and plastic architecture (65). Duany Plater Zyberk & Company believe that this only reinforces a destructive pattern of growth in an endless quest to move away from the sprawl that only results in creating more of it (Duany Plater-Zyberk 26).