Introduction to Urban Sprawl Notes

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CHAPTER
10
Urbanization
Growing Pains in Portland,
Oregon
• Senate Bill 100 sets guidelines for land use in Oregon,
restricting development to urban areas and leaving
open areas largely untouched.
• In recent years, further measures have challenged
Senate Bill 100, arguing that it restricts landowners
from increasing the value of their property through
development.
Talk About ItShould governments be able to limit
development on privately owned land if it means
protecting the environment? Why or why not?
Lesson 10.1 Land Use and Urbanization
For the first time in history, there
are now more urban residents than
rural residents.
Lesson 10.1 Land Use and Urbanization
Land Cover and Land Use
• Land cover: Vegetation and structures that cover land.
• Land use: Human activities that occur on land
• Humans change land cover, especially in urban areas.
These changes have environmental and economic effects.
Lesson 10.1 Land Use and Urbanization
Urban and Rural Areas
• Urban: Land mostly
covered with buildings and
roads (includes suburbs)
• Rural: Any other type
of land use or land
cover (includes forests,
cropland, etc.)
Lesson 10.1 Land Use and Urbanization
Urbanization
• Occurs when people
move from rural areas
to cities
• Cities are not new, but
the enormous size of
today’s cities is. More
than 20 cities have at
least 10 million residents.
Lesson 10.1 Land Use and Urbanization
The Rise of Cities
• Factors that contribute
to the rise of
urbanization include
population growth and
industrialization.
• Most cities are located
near a transportation
route such as a large
body of water, railroad,
or highway.
Chicago’s location on Lake Michigan helped it
grow into a large and prosperous city.
Did You Know?Since 1950, the world’s
urban population has more than quadrupled.
According to U.N. projections, it will double
again by 2050.
Lesson 10.1 Land Use and Urbanization
Environmental Costs of
Urbanization
• Pollution: Increased waste, industrial byproducts, noise
pollution, light pollution
• Heat islands: Cities, several
degrees warmer than
surrounding areas, affect
local weather and
trap pollutants.
• Imported resources: Fossil
fuels are burned to import
food, water, fuel, and
raw materials.
Lesson 10.1 Land Use and Urbanization
Environmental Benefits
of Urbanization
• Efficiency: Less fuel and resources
needed to distribute goods and
services to residents
• Universities and research centers:
Urban areas tend to foster education
and innovation.
• Land Preservation: Dense urban
centers leave room for agriculture,
wilderness, biodiversity, and privacy.
Lesson 10.2 Sprawl
In 1950, 65% of the U.S. population lived in urban
(including suburban) areas, while 35% lived rurally.
In 2010, 89% was urban and only 11% rural.
Los Angeles, CA,
is one the most
sprawling U.S.
cities.
Lesson 10.2 Sprawl
What Is Sprawl?
• The spread of low-density urban or suburban development
outward from a dense urban core
• Often, growth of suburban areas outpaces population growth
because suburbs allow more space per person than cities.
Las Vegas, Nevada
Left: 1972;
Right: 2002
Lesson 10.2 Sprawl
Primary Contributors to Sprawl
• Population growth
• Increased per capita
land consumption
• On average, these two
factors are equally
important, but one may
be more important than
another in a specific city.
Lesson 10.2 Sprawl
Patterns of Sprawl
• Uncentered commercial strip development
• Low-density single-use residential development
• Scattered, or leapfrog, development
• Sparse street network
Lesson 10.2 Sprawl
Impacts of Sprawl
• Transportation: Little to no
public transportation
• Pollution: Increased driving
leads to pollution.
• Public health: May promote
inactivity, and by extension
obesity and high blood
pressure
• Land Use: Less land left as
open space, forests, and farms
• Economics: Wealth tending to
concentrate in suburbs, leaving
urban areas poor
Did You Know?Every year, more than
1 million hectares (2.5 million acres) of
rural land are converted to urban land
in the United States.
Lesson 10.3 Sustainable Cities
More than 600 “new urbanist”
communities are planned or in
construction across North America.
Lesson 10.3 Sustainable Cities
City Planning and Zoning
• City planners attempt to design cities that both work well
and look and feel appealing.
• Zoning: Classification of land areas for different types of
development and
land use
• An area can be
mixed use or
single use.
• Involves
restrictions on
the use of
private land
Lesson 10.3 Sustainable Cities
Urban Growth Boundaries (UGBs)
• A line drawn around a city to
separate urban areas from rural
areas, with limited permission
for development
• Advantages: Saves 20% in
infrastructure costs compared
with sprawl; decreases per capita
land use; promotes economic
development within the city
• Disadvantages: Does not
completely stop sprawl; limits
rights of private landowners
Lesson 10.3 Sustainable Cities
Smart Growth
• Focuses on economic
and environmental
approaches to avoiding
sprawl
• Builds “up,” not “out”
• Maintains open spaces
by redeveloping existing
urban areas, waterfronts,
and industrial sites
Lesson 10.3 Sustainable Cities
“New Urbanism”
• Seeks to design
neighborhoods that
minimize the need to
drive
• Requires good public
transportation systems
• Sometimes impossible
due to zoning
restrictions
Did You Know?A 2004 study found
that residents of sprawling areas were
heavier on average for their height,
and had increased instances of high
blood pressure.
Lesson 10.3 Sustainable Cities
Transportation Options
• Public transportation a key factor in the quality of urban life
• Buses, subways, trains more efficient, less polluting than cars
• Cities encourage mass transit with fuel taxes, vehicle taxes,
rewarding carpoolers, and encouraging bicycle and bus use.
Did You Know?Paris, France
removed 200,000 parking spaces
to encourage the use of public
transportation within the city.
Lesson 10.3 Sustainable Cities
Open Space
• Provides greenery, beauty, freedom of movement,
recreation opportunities
• Includes parks, playgrounds, community gardens,
greenways
• Regulates climate,
produces oxygen,
filters air and water,
provides habitat
Did You Know?More than
24,000 km of abandoned
public rail line in the U.S.
have been converted to
trails for walking, jogging,
and biking.
Lesson 10.3 Sustainable Cities
Green Building Design
• The goals of a green
building are to save
energy and resources
without sacrificing
people’s comfort.
• Ashland High School
near Boston,
Massachusetts is a
sophisticated green
building that saves the
school system more
than $75,000 a year in
energy costs.
Lesson 10.3 Sustainable Cities
Urban Sustainability Successes
• Curitiba, Brazil
• Efficient bus network
• Recycling and environmental
education provided
• New York City
• Plan underway to reduce
greenhouse gas emissions,
improve public transit, plant
trees, clean up polluted sites,
and improve open space access
The tube at this Curitiba bus stop handles fare
collection for passengers boarding or exiting.
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