Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Urbanization and Sustainable Cities Chapter 24

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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 world population now lives in urban areas.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. What Is A City ? US 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Urban and Rural Growth

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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. - Nineteen cites currently have populations larger than 5 million.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. World Urbanization Some futurists predict 93 cities with a population of at least 5 million by  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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. World Urbanization

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Immigration Push Factors Overpopulation Economics Politics Racial or Religious Conflicts Land Tenure Changes in Agriculture  Large Monoculture Farms

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Immigration Pull Factors Excitement and Vitality Jobs Housing Entertainment Social Mobility and Power Specialization of Professions

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Current World Problems - Housing  At least 1 million people live in slums of central cities and in shantytowns in the outskirts of cities.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Current World Problems 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Current World Problems 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 US agricultural land annually.  Planning authority is often divided among many small local jurisdictions.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Urban Sprawl Because many Americans live far from work, they consider a private automobile essential.  Average US 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 US $78 billion annually in wasted fuel and time.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Designing For Open Space

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. SUSTAINABLE DEVELOPMENT IN THE THIRD WORLD 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.

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed. Summary: 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

Cunningham - Cunningham - Saigo: Environmental Science 7 th Ed.