Since ancient times, residential areas were built outside cities. When cities were surrounded by walls and ran out of room for more housing, new residential areas were built beyond the walls. As cities grew rapidly during the nineteenth century as part of the Industrial Revolution, more extensive residential areas appeared.

Key Issue 3: Why Do Urban Areas Expand?

Suburbs have existed on a small scale since ancient times; residential areas were often located outside the walls surrounding a city. As cities grew rapidly during the nineteenth century, as part of the Industrial Revolution, more extensive suburbs developed.

Origin and Growth of Suburbs A suburb is a residential or commercial area situated within an urban area but outside the central city. In 1950, only 20 percent of Americans lived in suburbs compared to 40 percent in cities, and 40 percent in small towns and rural areas. The percentage living in suburbs rose rapidly thereafter.

Annexation The process of legally adding land area to a city is annexation. Normally, land can be annexed to a city only if a majority of the residents in the affected area vote in favor of the annexation. Peripheral residents generally desired annexation in the nineteenth century because the city offered better services, such as water supply, sewage disposal, trash pickup, paved streets, public transportation, and police and fire protection. Today, cities are less likely to annex peripheral land because residents prefer to organize their own services rather than pay the city taxes for them.

Suburban Lifestyle Suburbs offer varied attractions—a detached single-family dwelling rather than a row house or an apartment, private land surrounding the house, space to park cars, and a greater opportunity for home ownership. By 1960, one-third of Americans lived in cities, one-third in suburbs, and one-third in small towns and rural areas. By 2000, 50 percent of Americans lived in suburbs compared to 30 percent in cities and 20 percent in small towns and rural areas.

Local Government Fragmentation Because MSAs in the United States are composed of many independent suburbs and central cities as well as counties, local governments are fragmented and less able to deal with regional problems. Most U.S. metropolitan areas have a council of governments, which is a cooperative agency consisting of representatives of the various local governments in the region. The council of governments may be empowered to do some overall planning for the area that local governments cannot logically do. Two kinds of strong metropolitan-wide governments have been established in a few places in North America: consolidations of city and county governments, and federations.

Suburban Sprawl Sprawl is the development of suburbs at relatively low density and at locations that are not contiguous to the existing built-up area. When private developers select new housing sites, they seek cheap land that can easily be prepared for construction – land often not contiguous to the existing built-up area. As a result, the peripheries of U.S. cities have pockets of development and gaps of open space. Sprawl incurs costs: local governments must spend more to extend roads and utilities to noncontiguous developments, more agricultural land, and trips to work and services use more energy because of the longer distances.

Density Gradient North American cities once followed a density gradient where density decreased consistently with increasing distance from the city center. Two changes have impacted the density gradient in recent years: fewer people living in the center and fewer differences in density within urban areas. These two changes flatten the density gradient and reduce the extremes of density between inner and outer areas traditionally found within cities. The construction of apartment and town houses in peripheral areas has increased density in those areas.

U.S. & U.K. Suburbs The supply of land for the construction of new housing is more severely restricted in European urban areas than in the United States. Officials try to limit sprawl by designating areas of mandatory open space. Several British cities are surrounded by greenbelts, or rings of open space. New housing is built either in older suburbs inside the greenbelts or in planned extensions to small towns and new towns beyond the greenbelts.

Smart Growth Some U.S. cities have pursued smart growth laws to limit sprawl. These laws and regulations seek to limit suburban growth and preserve farmland.

Suburban Segregation Many suburbs display two forms of segregation:

· Residential segregation Housing in a given suburban community is usually built for people of a single social class, with others excluded by virtue of the cost, size, or location of the housing. Segregation by race and ethnicity also persists in some suburbs.

· Commercial segregation Residents are separated from commercial and manufacturing activities that are confined to compact, distinct areas.

Residential Segregation People with low incomes and minorities are less likely to live in many U.S. suburbs because of the high cost of the housing and unwelcoming attitudes of established residents. Suburban communities discourage the entry of those with lower incomes and minorities because of fear that property values will decline if the high-status composition of the neighborhood is altered.

The homogeneity in suburban communities is legally protected through zoning ordinances. A zoning ordinance is a law that limits the permitted uses of land and maximum density of development in a community. Zoning ordinances typically identify districts designed only for single-family houses, apartments, industry, or commerce.

Suburban Consumer Services Consumer services have expanded to the suburbs because most of their customers live in the suburbs. Retailing has become increasingly concentrated in planned suburban shopping malls. In recent years shopping malls have lost customers due to the ready availability of online shopping services.

Suburban Business Services Offices that do not require face-to-face contact are increasingly moving to suburbs, where rents are lower than in the CBD. For some workers suburban office locations can pose hardships. Secretaries, custodians, and other lower-status office workers may not have cars and public transportation may not serve the site. Factories and warehouses have relocated to the suburbs for more space, cheaper land, and better truck access. Suburban locations facilitate truck shipments by providing good access to main highways and no central city traffic congestion.

Reliance on Motor Vehicles The average American travels 37 miles per day. In the United States,

83 percent of trips in the United States are by car or truck, 12 percent are by walking or biking, 2 percent each are by public transport or school bus, and 1 percent is by other means.

Transportation Epochs Transportation improvements have played a crucial role in the changing structure of urban areas. Geographer John Borchert identified five eras of U.S. urban areas resulting from changing transportation systems:

· Sail-Wagon Epoch (1790–1830)

· Iron Horse Epoch (1830–1870)

· Steel Rail Epoch (1870–1920)

· Auto-Air-Amenity Epoch (1920–1970)

· Satellite-Electronic Jet Propulsion (1970–?)

Cities have prospered or suffered during the various epochs, depending on their proximity to economically important resources and migration patterns. Parallel to this, cities retain physical features from the earlier eras that may be assets or liabilities in subsequent eras.

Benefits & Costs of Motor Vehicles There are around 1.3 billion motor vehicles in the world, including 275 million in the United States. The perceived cost and comfort, choice, and flexibility of motor vehicles has maintained the mode of transportation’s dominance in the United States. Most motorists perceive that the cost of using vehicles is less than the cost of using public transportation. Motor vehicles have environmental costs. The consumption of land is one unseen costs of motor vehicle culture. An average city allocates about one-fourth of its land to roads and parking lots. Congestion is an issue not often considered by motorists as well; the average American wastes about 19 gallons of fuel and loses 42 hours per year sitting in traffic jams. The U.S. government encourages the use of cars and trucks by paying 90 percent of the cost of limited access, high-speed interstate highways, which stretch for 48,000 miles across the country. U.S. policies also keep fuel prices cheaper than those found in Europe, further supporting the use of motor vehicles.

Legacy of Public Transport in the United States Public transit is better suited than motor vehicles to moving large numbers of people because each transit traveler takes up far less space. Public transport is cheaper, less polluting, and more energy efficient than privately operated motor vehicles. The heaviest flow of commuters into the CBD is in the morning and out of it in the evening. Rush hour is the four consecutive 15-minute periods that have the heaviest traffic.

Public Transit Around the World Public transit is classified as heavy rail (underground subways and elevated trains), light rail (trams and streetcars), and bus. According to varied sources, there are 178 cities with underground heavy-rail systems in operation in 2017 and 401 cities with light-rail systems in operation as of 2018. Cities with existing service have been expanding them. A greater importance is placed on public transportation outside of the United States.

Public Transport in the United States In the nineteenth century expansion of cities was limited by poor transportation as people needed to live near their place of employment. Suburbanization in the twentieth century relied on motor vehicles and provided residents with greater flexibility in housing location.

Recent Trends in Public Transport Public transport is used primarily for workers commuting in and out of the CBD. Public transport declined in the 1970s, but ridership increased from 8 billion in 1995 to 10 billion in 2017. Light-rail lines have increased, and seven cities opened entirely new subway systems between 1972 and 1993.

Challenges Facing Public Transit Public transportation in the United States is caught in a vicious circle because fares do not cover operating costs. As patronage declines and expenses rise, the fares are increased, which drives away passengers and leads to service reductions and still higher fares. Public expenditures to subsidize construction and operating costs have increased, but the United States does not fully recognize that public transportation is a vital utility deserving of a large subsidy. The minimal level of public transit service in most U.S. cities means that low-income people may not be able to reach places of employment.

13.3

Boomburbs A suburban city that is rapidly growing, is as large as a major city, but retains its suburban feel

Council of government Cities and counties coming together for coordination and urban planning

De facto segregation Racial segregation that happens organically instead of being enforced by law

Density gradient The change in density in an urban area from the center to the periphery.

Environmental injustice When marginalized groups face higher levels of environmental risk due to others actions

Exurbs An area outside of the denser inner suburban area which has an economic and commuting connection to the metro area, low housing density, and growth

Greenbelt An area of open land around a city where development is prohibited

Nonbasic business A business that sells its products primarily to consumers in the community.

Rush hour The four consecutive 15-minute periods in the morning and evening with the heaviest volumes of traffic.

Slow-growth cities Cities that are actively trying to control their growth to promote sustainability

Smart growth Planned urban development that aims to reduce environmental effects

Sprawl Development of new housing sites at relatively low density and at locations that are not contiguous to the existing built-up area.

Suburb A residential or commercial area situated within an urban area but outside the central city.

Suburban Sprawl The expansion of a city away from urban centers outward with a tendency to turn into suburbs farther out Development of new housing sites at relatively low density and at locations that are not contiguous to the existing built-up area.

Suburbanization A population shift from central urban areas into suburbs