Urbanization and Sustainable Cities

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Urbanization and Sustainable Cities
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Outline

• Urbanization
• Causes of Urban Growth
• Push and Pull Factors
• Current Urban Problems
• Developing World
• Developed World
• Urban Sprawl
• Open Space
• Sustainable Development of the Third World

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URBANIZATION

• Vast majority of humanity has always lived in
  rural areas where natural resource-based
  occupations provided support.
• Since beginning of Industrial Revolution cites
  have grown rapidly in size and power.
• Urbanization - Increasing concentration of
  population in cites and transformation of land
  use and society to metropolitan patterns of
  organization.
• Nearly half of world population now lives in
  urban areas.

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What Is A City ?

• U.S. Census Bureau considers any incorporated
  community a city, and any city with more than
  2,500 residents as urban.
• In rural areas, most residents depend on natural
  resources for their livelihood.
• In urban areas, most people are not directly
  dependent on natural resource-based occupations.

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What Is A City ?

• A village is a collection of rural households
  linked by culture, customs, family ties, and
  association with the land.
• A city has a large enough resource base to allow
  residents to specialize in arts, crafts,
  services, or professions other than
  resource-based occupations.
• A megacity is an urban area with more than 10
  million inhabitants.

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World Urbanization

• In 1850, only 2 of world population lived in
  cities.
• By 2000, 47 of world population lived in urban
  areas.
• Only Africa and South Asia remain predominantly
  rural.
• Expected that 90 of population growth over the
  next 25 years will occur in less-developed
  countries.

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World Urbanization

• Urban growth has been particularly dramatic in
  the largest cities, especially in the developing
  world.
• A century ago, London was the only city with more
  than 5 million people.
• Thirty cities currently have populations larger
  than 5 million.

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World Urbanization

• Some futurists predict 93 cities with a
  population of at least 5 million by 2025.
• Three-fourths in developing world.
• In developing world megacities, as much as half
  of urban population are transient workers or
  residents of shanty towns.
• By some estimates, Mexico City has a current
  population of 25 million, and grows by 750,000
  each year.

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CAUSES OF URBAN GROWTH

• Two main avenues of urban growth
• Natural Increase
• Fueled by improved food supplies and medical
  care.
• Immigration
• Caused by push factors forcing people out of the
  country, and pull factors drawing them into
  cities.

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Immigration Push Factors

• Overpopulation
• Economics
• Politics
• Racial or Religious Conflicts
• Land Tenure
• Changes in Agriculture
• Large Monoculture Farms

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Immigration Pull Factors

• Excitement and Vitality
• Jobs
• Housing
• Entertainment
• Social Mobility and Power
• Specialization of Professions

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Government Policies

• Government policies often favor urban over rural
  areas in push and pull factors.
• Developing countries often spend majority of
  budgets on improving urban areas.
• Major cities gain a monopoly on new jobs,
  education and general opportunities.

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CURRENT URBAN PROBLEMS

• Developing World
• Uncontrollable Growth
• Traffic and Congestion
• Air Pollution
• Sewer Systems and Water Pollution
• Only 35 of urban residents in developing world
  have satisfactory sanitation.
• About same percentage do not have safe drinking
  water.

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Current World Problems

• Housing
• At least 1 billion people live in slums of
  central cities and in shantytowns in the
  outskirts of cities.
• Around 100 million people have no home at all.

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Current World Problems

• The Developed World
• Rapid growth of cities that accompanied
  industrialization has mostly slowed or reversed.
• Many of the environmental problems have been
  reduced.
• Many of major polluters have moved to developing
  countries.

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Developed World

• Urban Sprawl
• In most American metropolitan areas, the bulk of
  new housing is in large, tract developments that
  leapfrog beyond city edges in search of
  inexpensive land.
• Consumes about 200,000 ha of U.S. agricultural
  land annually.
• Planning authority is often divided among many
  small local jurisdictions.

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Urban Sprawl

• Because many Americans live far from work, they
  consider a private automobile essential.
• Average U.S. driver spends 443 hours per year
  behind a steering wheel.
• In some metropolitan areas, it is estimated
  one-third of all land is devoted to automobile
  infrastructure.
• Traffic congestion costs U.S. 78 billion
  annually in wasted fuel and time.

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Urban Sprawl

• With a reduced tax base and fewer civic leaders
  living or working in downtown areas, the city is
  unable to maintain its infrastructure.
• Low density development of suburbs is racially
  and economically exclusionary because it provides
  no affordable housing and makes a viable public
  transit system impractical.

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Smart Growth

• Smart Growth makes efficient and effective use of
  land resources and existing infrastructure by
  encouraging in-fill development.
• Also attempts to provide a variety of
  transportation options.
• Goal is staged, managed growth that protects
  environmental quality and diversity.

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Garden Cities and New Towns

• New Towns - Numerous experiments to try and
  combine best features of rural village and modern
  city.
• Ebenezer Howard (1898) proposed congestion of
  London could be relieved by moving whole
  neighborhoods to garden cities separated from the
  central city by a greenbelt of forest and fields.

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New Urbanist Movement

• Limit city size, or organize into modules of
  30,000 to 50,000 people.
• Determine in advance where development will take
  place.
• Turn shopping malls into city centers.
• Locate everyday services more conveniently.
• Increase jobs in a community by locating offices
  and commercial centers near suburbs.
• Encourage walking and low-speed vehicles.

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New Urbanist Movement

• Promote diversity in housing designs.
• Create housing superblocks.
• Make cities more self-sustainable.
• Incorporate rooftop gardens or vegetation.
• Invite public participation in decision-making.

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Designing for Open Space

• Traditional suburban development typically
  divides land into a checkerboard layout of nearly
  identical 1-5 ha parcels with no designated open
  space.
• Conservation Development - Preserves at least
  half of a subdivision as natural areas, farmland,
  or other forms of open space.

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Designing for Open Space
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SUSTAINABLE DEVELOPMENT IN POORER COUNTRIES

• Many planners argue social justice and
  sustainable economic development are answers to
  urban problems.
• Another important measure of progress may be
  institution of social welfare providing care to
  the sick and elderly.
• Others argue the best hope for developing
  countries may be to delink from established
  international economic systems and develop
  self-sustainability.

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Summary

• Urbanization
• Causes of Urban Growth
• Push and Pull Factors
• Current Urban Problems
• Developing World
• Developed World
• Urban Sprawl
• Open Space
• Sustainable Development in Poorer Countries

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