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C o r e C a s e s t u d y

22 Cities and Sustainability

The Ecocity Concept in Curitiba, Brazil

Urban planners envision large portions of the growing human population living in more environmentally sustainable cities, called ecocities or green cities. This is not just a futuristic dream. One such ecocity is Curitiba (“koor-i-TEE-ba”), a city of 3.2 mil-lion people known as the “ecological capital of Brazil.”

In 1969, planners in this city decided to focus on creating an efficient mass transit system rather than on accomodating a growing number of cars. Curitiba now has the world’s best bus system, in which clean and modern buses transport about 72% of all commuters every day throughout the city using express lanes dedicated to buses (Figure 22-1). Only high-rise apartment

buildings are allowed near major bus routes, and each building must devote its bottom two floors to stores—a practice that reduces the need for residents to travel.

Cars are banned from 49 blocks in the center of the down-town area, which has a network of pedestrian walkways con-nected to bus stations, parks, and bicycle paths running through-out most of the city. Consequently, Curitiba uses less energy per person and has lower emissions of greenhouse gases and other air pollutants, as well as less traffic congestion than do most comparable cities.

The city transformed flood-prone areas along its six rivers into a series of interconnected parks. Volunteers have planted more than 1.5 million trees throughout the city, none of which can be cut down without a permit, which also requires that two trees must be planted for each one that is cut down.

Curitiba recycles roughly 70% of its paper and 60% of its metal, glass, and plastic, which is collected from households three times a week. Recovered materials are sold mostly to the city’s more than 500 major industries, which must meet strict pollution standards. Most of these businesses are located in an industrial park outside the city limits. A major bus line runs to the park, but many of the workers live nearby and can walk or bike to work.

The poor receive free medical and dental care, child care, and job training, and 40 feeding centers are available for street chil-dren. Poor people can exchange filled garbage bags for surplus food, bus tokens, and school supplies. Also, the city has a build-it-yourself program that gives a poor family a plot of land, building materials, two trees, and an hour’s consultation with an architect.

This internationally acclaimed model of urban planning and sustainability is the brainchild of architect and former college professor Jaime Lerner, who has served as the city’s mayor three times since 1969. When its transformation began, Curitiba was no more well off than any other Brazilian city. In 1980, its per capita GDP was only 10% above the average for Brazil. By 1996, it was 65% above average. Its economy did well partly because companies were attracted to the city’s pleasant environment, lack of congestion, and ease of commuting.

Curitiba now faces new challenges, as do all cities, mostly because of increasing population pressure. Throughout this chap-ter, we will examine these challenges and some possible solutions for Curitiba and other urban areas.

Figure 22-1 solutions: This bus rapid transit (BRT) system in Curitiba, Brazil, moves large numbers of passengers around rapidly because each of the system’s five major “spokes,” connecting the city center with outlying districts, has two express lanes used only by buses. Double- and triple-length bus sections are coupled together as needed to carry up to 300 passengers. Boarding is speeded up by the use of extra-wide bus doors and boarding platforms under glass tubes where passengers can pay before getting on the bus (top left).

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Key Questions and Concepts

22-1 What are the major population trends in urban areas?ConCept 22 - 1 Urbanization continues to increase steadily and the numbers and sizes of urban areas are growing rapidly, especially in less-developed countries.

22-2 What are the major urban resource and environmental problems?ConCept 22 -2 Most cities are unsustainable because of high levels of resource use, waste, pollution, and poverty.

22-3 How does transportation affect urban environmental impacts?ConCept 22 -3 In some countries, many people live in dispersed urban areas and depend mostly on motor vehicles for their transportation, which greatly expands their ecological footprints.

22-4 How important is urban land-use planning? ConCept 22 -4 Urban land-use planning can help to reduce uncontrolled sprawl and slow the resulting degradation of air, water, land, biodiversity, and other natural resources.

22-5 How can cities become more sustainable and livable?ConCept 22 -5 An ecocity allows people to choose walking, biking, or mass transit for most transportation needs; to recycle or reuse most of their wastes; to grow much of their food; and to protect biodiversity by preserving surrounding land.

Note: Supplements 2 (p. S3), 3 (p. S6), 8 (p. S30), and 9 (p. S57) can be used with this chapter.

The city is not an ecological monstrosity. It is rather the place where both the problems and the opportunities of modern technological civilization are most potent and visible.

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22-1 What Are the Major Population Trends in Urban Areas?

ConCept 22-1 urbanization continues to increase steadily and the numbers and sizes of urban areas are growing rapidly, especially in less-developed countries.

Half of the World’s People Live in Urban AreasPeople live in urban areas, or cities (Figure 22-2, top, p. 588), suburbs that spread out around city centers (Figure 22-2, middle), and rural areas or villages (Fig- ure 22-2, bottom). Urbanization is the creation and growth of urban and suburban areas. It is measured as the percentage of the people in a country or in the world living in such areas. Urban growth is the rate of increase of urban populations.

The world’s first cities emerged about 6,000 years ago. The first city to reach a population of 1 million was Rome, Italy, in 133 bc. Since then, the world has become increasingly urbanized. Today, half of the world’s peo-ple, and 79% of Americans, live in urban areas.

Urban areas grow in two ways—by natural increase (more births than deaths) and by immigration, mostly from rural areas. Rural people are pulled to urban areas

in search of jobs, food, housing, educational opportu-nities, better health care, and entertainment. Some are also pushed from rural to urban areas by factors such as poverty, lack of land for growing food, declining agricul-tural jobs, famine, war, and religious, racial, and politi-cal conflicts.

People are also pushed or pulled to cities by gov-ernment policies that favor urban over rural areas. For example, less-developed countries tend to spend most of their budgets on economic development and job creation in urban areas. Some governments establish lower food prices in urban areas, which reward city dwellers, help to keep leaders in power, and attract the rural poor.

Four major trends in urban population dynamics have emerged, and they are important for understand-ing the problems and challenges of urban growth. First, the proportion of the global population living in urban areas is increasing. In 1900, the average population of the

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588 ChaPTEr 22 Cities and Sustainability

world’s biggest 100 cities was about 700,000. By 2009, that average had climbed to 6 million.

Between 1850 and 2009, the percentage of people living in urban areas increased from 2% to 50%, and it could reach 66% by 2030. About 88% of this growth will occur in already overcrowded and economically stressed cities in less-developed countries, where four of every ten people live in urban areas (Figure 22-3). In each of the two largest of these countries, China and India, more than 25 million people move to cities each year.

Second, the numbers and sizes of urban areas are mush-rooming. Every week, more than 1 million people are added to the world’s urban areas. Between 2008 and 2015, the number of urban areas with a million or more people is projected to increase from 400 to 564. Demographers project that by 2025, China will add 60 new cities, each hosting 1.5 million to 5 million peo-ple. By comparison, the United States currently has just 9 cities of more than 1 million people. Between 2010 and 2030, China will add more city dwellers than the entire current population of the United States.

Currently, there are 18 megacities or megalopolises—cities with 10 million or more people—up from 8 in 1985. Fifteen of them are in less-developed countries (Figure 22-4). Such megacities will soon be eclipsed by hypercities each having more than 20 million people. Tokyo, Japan, is the leading city in this category, hav-ing 32 million people—more than the entire population of Canada. But according to UN projections, by 2015, Tokyo, Japan, Mumbai (formerly Bombay) and Delhi in India, Dhaka, Bangladesh, and São Paulo, Brazil, will be the top five most populated cities. All of them, along with Lagos, Nigeria, are projected to become hypercities by then.

Figure 22-2 About half of the world’s people live in urban areas, or cities, such as Shanghai, China (top), and their surrounding suburban areas such as this one in Southern California (middle). The other half live in rural areas—in villages such as this one in the southern African country of Malawi (bottom), in small towns, or in the countryside.

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Third, urban growth is much slower in more-developed countries than in less-developed countries (Figure 22-3). However, more-developed countries, now with 75% urbanization, are projected to reach 81% urbanization by 2030.

Fourth, poverty is becoming increasingly urbanized, mostly in less-developed countries. The United Nations esti-mates that at least 1 billion people in less-developed countries (more than three times the current U.S. popu-lation) live in crowded and unsanitary slums and shan-tytowns within most cities or on their outskirts; within 30 years this number may double.

thinking about urban trends

If you could reverse one of the four urban trends discussed here, which one would it be? Which of these trends has Curitiba, Brazil, (Core Case study) reversed?

If you visit a poor, over-crowded area of a large city in a less-developed country, your senses may be over-whelmed by a vibrant but chaotic crush of people, vehi-cles of all types, traffic jams (Figure 22-5), noise, and odors, including smoke from burning trash, as well as from wood and coal cooking fires, and raw sewage. Many people sleep on the streets or live in crowded,

unsanitary, rickety, and unsafe slums and shantytowns with little or no access to safe drinking water or modern sanitation facilities.

Figure 22-4 Global outlook: Major urban areas throughout the world are revealed in these satellite images of the earth at night, showing city lights. Currently, the 50% of the world’s people who live in urban areas occupy about 2% of the earth’s land area. Note that most of the urban areas are found along the continental coasts, which explains why most of Africa and much of the interior of South America, Asia, and Australia are dark at night. This figure also shows the populations of the world’s 18 megacities (each with 10 million or more people) in 2010. All but three are located in less-developed countries. Question: In order, what were the world’s five most populous cities in 2010? (Data from National Geophysics Data Center, National Oceanic and Atmospheric Administration, and United Nations)

Los Angeles15.2 million

Cairo14.5 million

Beijing22 million

Tokyo32 million

Shanghai17 million

Mexico City20.5 million

New York19.7 million

London12.9 million

São Paulo18.9 million

Rio de Janeiro12 million

Buenos Aires13.1 million

Karachi11.8 million

Dhaka13 million

Mumbai(Bombay)19.2 million

Osaka17.4 million

Jakarta18.9 million

Hong Kong15.8 million

Manila16.3 million

Seoul20.6 million

Kolkata(Calcutta)15.1 million

Lagos13.4 million

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Figure 22-5 This is a typical daily traffic jam of people, carts, bicycle taxis, and other vehicles in an older section of Delhi, India—a city with 13 million people.

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ConCEPT 22-1 589


■ Case study

Urbanization in the United States Between 1800 and 2008, the percentage of the U.S. population living in urban areas increased from 5% to 79%. This population shift has occurred in four phases.

First, people migrated from rural areas to large central cities. Currently, three-fourths of Americans live in cities with at least 50,000 people, and nearly half live in urban areas with 1 million or more residents (Figure 22-6).

Second, many people migrated from large central cities to smaller cities and suburbs. Currently, about half of urban Americans live in the suburbs (Figure 22-2, middle), nearly a third in central cities, and the rest in rural housing developments beyond suburbs.

Third, many people migrated from the North and East to the South and West. Since 1980, about 80% of the U.S. population increase has occurred in the South and West. Between 2009 and 2043, demographers project that the fastest growing U.S. states will continue to be Nevada, Arizona, and Florida, although increased drought and heat waves due to projected climate change may alter

this trend. According to a 2006 study by the Center for Environment and Population, the South and West also contain many of the country’s ecological hot spots (see Figure 27 on p. S55 in Supplement 8) where biodiver-sity is threatened.

Fourth, since the 1970s, and especially since 1990, some people have fled both cities and suburbs, and migrated to developed areas outside of suburbs. The result is rapid growth of exurbs—housing developments scattered over vast areas that lie beyond suburbs and have no socio-economic centers.

Since 1920, many of the worst urban envi-ronmental problems in the United States have been reduced significantly (Figure 6-7, p. 132). Most people have better working and housing conditions, and air and water quality have improved. Better sanita-tion, clean public water supplies, and medical care have slashed death rates and incidences of sickness from infectious diseases. Concentrating most of the popula-tion in urban areas also has helped to protect the coun-try’s biodiversity by reducing the destruction and degra-dation of wildlife habitat.

GOODNEWS

Figure 22-6 The major urban areas in the United States are revealed in satellite images of the earth at night show-ing city lights (top). About eight of every ten Americans live in urban areas, which occupy a small but growing fraction of the country’s land area. The cities identified in the image are the fastest-growing metropolitan areas. Nearly half (48%) of all Americans live in cities of 1 million or more people, most of which are projected to merge into huge urban areas shown as shaded sections in the bottom map. Question: Why are many of the largest urban areas located near water? (Data from National Geophysical Data Center/National Oceanic and Atmospheric Admin-istration, U.S. Census Bureau)

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However, a number of U.S. cities—especially older ones—have deteriorating services and aging infrastruc-tures (streets, bridges, dams, power lines, schools, waste management, water supply pipes, and sewers). Indeed, according to a 2009 study by the American Society of Civil Engineers (ASCE), the United States has fallen $2.2 trillion behind in maintaining its vital public infrastruc-ture of roads, bridges, sewer systems, dams, and schools. This amounts to more than $7,000 for each U.S. citizen.

The ASCE president warned that “crumbling infra-structure has a direct impact on personal and economic health.” For example, the ASCE report found that aging sewer systems allow huge volumes of untreated waste-water to flow into U.S. waterways every year. This results in pollution of many urban streams and beaches, as well as the potential for contaminating groundwater and surface water.

At a time when there are urgent needs to upgrade rapidly deteriorating infrastructure, many U.S. cities face budget crises and the resulting cuts to public services, as businesses and people move to the suburbs and exurbs, and city revenues from property taxes decline. The eco-nomic recession beginning in 2008 has worsened this situation, as city and state budgets have suffered from declining tax revenues. In hard times, funds for main-taining infrastructure are usually the first to be cut.

Urban Sprawl Gobbles Up the CountrysideIn the United States and some other countries, urban sprawl—the growth of low-density development on the edges of cities and towns—is eliminating surround-ing agricultural and wild lands (Figure 22-7). It results in a far-flung hodgepodge of housing developments, (Figure 22-2, middle) shopping malls, parking lots, and office complexes that are loosely connected by multi-lane highways and freeways.

Five major factors promoted urban sprawl in the United States. First, ample land was available for most cities to spread outward. Second, low-cost gasoline combined with federal and state funding of highways encouraged automobile use and the development of outlying tracts of land. Third, starting around 1950, fed-eral government home loan guarantees for World War II veterans stimulated the development of suburbs; since then, tax laws have encouraged home owner-ship. Fourth, most state and local zoning laws favored large residential lots and the separation of residential and commercial areas. Fifth, most urban areas consist of multiple local governments, which rarely work together to develop an overall plan for managing urban growth. Similar processes have occurred in other countries.

Figure 22-7 These satellite images show the growth of urban sprawl in and around the U.S. city of Las Vegas, Nevada, between 1973 and 2003—a process that continues. Between 1970 and 2009, the population of water-short Clark County, which includes Las Vegas, more than quadrupled from 463,000 to around 1.9 million, making it one of the nation’s fastest-growing urban areas. Question: What might be a limiting factor on population growth in Las Vegas?

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As they grow outward, separate urban areas some-times merge to form a megalopolis. For example, the remaining open spaces between the U.S. cities of Bos-ton, Massachusetts, New York, New York, and Washing-ton, DC, are rapidly urbanizing (Figure 22-6, bottom). The result is an almost 800-kilometer-long (500-mile-long) urban area that contains about 35 million people and is often called Bowash. Other such megalopolises include the areas between Amsterdam, the Netherlands, and Paris, France, in Europe; Japan’s Tokyo–Yoko-hama–Osaka–Kobe corridor known as Tokohama (with nearly 50 million people); and the Brazilian industrial triangle made up of São Paulo, Rio de Janeiro, and Belo Horizonte.

In a nutshell, urban sprawl is the product of afford-able land, automobiles, cheap gasoline, and little or no urban planning. Many people prefer living in suburbs and exurbs. Compared to central cities, these areas pro-vide lower-density living and access to larger lot sizes and single-family homes. Often these areas also have newer public schools and lower crime rates.

However, urban sprawl has caused or contributed to a number of environmental problems. Because of non-existent or inadequate mass transportation in most such areas, sprawl forces people to drive everywhere, and in the process, their vehicles consume significant amounts of gasoline while emitting greenhouse gases and other forms of air pollution. Sprawl has decreased energy effi-ciency, increased traffic congestion, and destroyed prime cropland, forests, and wetlands.

Urban sprawl also has led to the economic deaths of many central cities, as people and businesses move out of these areas. In addition, a similar but new problem has arisen since 2000—the growing decay of suburban shopping centers. As cheap credit has dried up, making

consumers less willing to use their credit cards, and as online shopping has replaced many car trips, numer-ous suburban shopping centers have closed. Some of these abandoned shopping centers are being recycled as apartment or office buildings and churches. Others will remain as crumbling eyesores or urban dinosaurs sur-rounded by vast empty parking lots on the outskirts of many cities.

Analysts at the Metropolitan Institute at Virginia Tech have suggested that this problem is deeper than an economic slump. They suggest that the suburban population of U.S. consumers is shrinking as the baby boomers (the large number of Americans born in the two decades after World War II) grow older. As a result, fewer suburban households have growing children, and many older Americans now prefer to live in more cul-turally diverse and interesting redeveloped central cit-ies. These analysts project that the year 2025 will see a surplus of 22 million large-lot homes in U.S. suburbs and exurbs.

Figure 22-8 summarizes these and other undesirable consequences of urban sprawl.

thinking about urban sprawl

Do you think the advantages of sprawl outweigh its disadvan-tages? What might happen to suburban and exurban areas as the prices of oil and gasoline rise sharply? How might this affect your lifestyle?

Examine how the San Francisco Bay area in the U.S. state of California grew in population between 1900 and 1990 at CengageNow.

Urban Sprawl

Natural Capital Degradation

Loss of cropland

Loss and fragmentation of forests, grasslands, wetlands, and wildlife habitat

Land andBiodiversity

Increased use and pollution of surface water and groundwater

Increased runoff and flooding

Water

Increased energy use and waste

Increased emissions of carbon dioxide and other air pollutants

Energy, Air,and Climate

Decline of downtown business districts

More unemployment in central cities

Economic Effects

Figure 22-8 These are some of the undesirable impacts of urban sprawl or car-dependent devel-opment. Question: Which five of these effects do you think are the most harmful?

ConCEPT 22-2 593

22-2 What Are the Major Urban Resource and Environmental Problems?

ConCept 22-2 Most cities are unsustainable because of high levels of resource use, waste, pollution, and poverty.

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Urbanization Has AdvantagesUrbanization has many benefits. From an economic standpoint, cities are centers of economic develop-ment, innovation, education, technological advances, and jobs. They serve as centers of industry, commerce, and transportation.

Urban residents in many parts of the world tend to live longer than do rural residents and to have lower infant mortality and fertility rates. They also have bet-ter access to medical care, family planning, education, and social services than do their rural counterparts. However, the health benefits of urban living are usually greater for the rich than for the poor.

Urban areas also have some environmental advan-tages. Recycling is more economically feasible because concentrations of recyclable materials and funding for recycling programs tend to be higher in urban areas. Concentrating people in cities helps to preserve biodi-versity by reducing the stress on wildlife habitats. Cen-tral cities also can save energy if residents rely more on energy-efficient mass transportation, walking, and bicy-cling, as they do in Curitiba, Brazil (Core Case study).

Urbanization Has Disadvantages Half of the world’s 6.9 billion people live in urban areas and each year, about 63 million people—an average of nearly 7,200 per hour—are added to these areas. Such intense population pressure and high population densi-ties (see Figure 6-1, p. 125) makes most of the world’s cities more environmentally unsustainable every year (Concept 22-2).

Even in more sustainable cities such as Curitiba, Brazil, (Core Case study) this pressure is taking its toll. The city’s once clear streams are often overloaded with pollutants. The bus system is nearing capacity, and car ownership is on the rise. While the recycling rate is still among the highest in the world, the region’s only landfill is now full. Architect Jorge Wilheim, who helped create Curitiba’s master plan, points out that the city’s population is now more than five times as large as it was in 1965 when the plan was drafted. With the metropolitan area’s population at 3.2 million, Wilheim believes it is time to adjust the plan.

We will touch on aspects of a possible new vision for Curitiba and similar solutions for other cities through-

out this chapter. Here we take a closer look at some sig-nificant problems faced by cities.

Cities Have Huge Ecological Footprints. Accord-ing to the Worldwatch Institute, although urban popu-lations occupy only about 2% of the earth’s land area, they consume about 75% of its resources and pro-duce about 75% of the world’s climate-changing CO2 emissions from human activities. Because of this high resource input of food, water, and materials, and the resulting high waste output (Figure 22-9, p. 594), most of the world’s cities have huge ecological footprints and are not self-sustaining systems (Concept 22-2).

While urbanization does help to preserve some of the earth’s biodiversity, large areas of land must be dis-turbed and degraded to provide urban dwellers with food, water, energy, minerals, and other resources. This decreases and degrades biodiversity, overall.

Thus, urban areas have huge ecological footprints that extend far beyond their boundaries. If you live in a city, you can calculate its ecological footprint by going to the website www.redefiningprogress.org/. (Also, see the Guest Essay on this topic by Michael Cain at CengageNOW.)

ConneCtionsurban Living and biodiversity awareness

Recent studies reveal that most urban dwellers live most or all of their lives in an artificial environment that isolates them from forests, grasslands, streams, and other natural areas that make up the world’s biodiversity. As a result, many urban residents tend to be uninformed about the importance of protecting not only the earth’s increasingly threatened biodi-versity but also its other forms of natural capital that support their lives and the cities in which they live.

Most Cities Lack Vegetation. In urban areas, most trees, shrubs, grasses, and other plants are destroyed to make way for buildings, roads, parking lots, and hous-ing developments. Thus, most cities do not benefit from vegetation that would absorb air pollutants, give off oxy-gen, provide shade, reduce soil erosion, provide wildlife habitats, and offer aesthetic pleasure. As one observer remarked, “Cities are places where they cut down most of the trees and then name the streets after them.”

Cities Often Have Water Problems. As cities grow and their water demands increase, expensive reservoirs

GOODNEWS


and canals must be built and deeper wells must be drilled. This can deprive rural and wild areas of surface water and can deplete underground water supplies.

Flooding also tends to be greater in some cities that are built on floodplains near rivers or along low-lying coastlines subject to natural flooding. In addition, cov-ering land with buildings, asphalt, and concrete causes precipitation to run off quickly and overload storm drains. Further, urban development has often destroyed or degraded large areas of wetlands that have served as natural sponges to help absorb excess storm water. Many of the world’s largest coastal cities (Figure 22-4) face a new threat of flooding some time in this century if sea levels rise as projected due to climate disruption (see Chapter 19, pp. 507–508).

For cities in arid areas that depend on water with-drawn from rivers and reservoirs that are fed by moun-taintop glaciers, projected climate change will likely cre-ate another problem. Those cities will face severe water shortages as atmospheric warming melts these moun-taintop glaciers.

For example, in some especially arid areas in the western United States (see Figure 13-5, p. 322) fed by the Colorado River (see Figure 13-1, p. 317) and Cal-ifornia’s water distribution system (see Figure 13-16, p. 331), irrigated agriculture may no longer be possible. For urban populations in some of these areas, this will lead to sharply rising food prices, because food will have to be shipped in from other areas. These urban dwellers will also face more water shortages, especially in areas where groundwater is being depleted (see Figure 13-9, p. 326).

The good news is that we have a variety of methods for reducing both groundwater deple-tion (see Figure 13-12, p. 327) and urban water use and waste (see Figure 13-23, p. 339).

Cities Concentrate Pollution and Health Problems. Because of their high population densities and high resource consumption, cities produce most of the world’s air pollution, water pollution, and solid and hazardous wastes. Pollutant levels are generally higher because

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Figure 22-9 natural capi-tal degradation: Urban areas are rarely sustainable systems. The typical city depends on large nonurban areas for huge inputs of mat-ter and energy resources, while it generates large outputs of waste matter and heat. According to an analy-sis by Mathis Wackernagel and William Rees, developers of the ecological footprint concept, London, England, requires an area 58 times as large as the city to supply its residents with resources (see area outlined in red on map below). They estimate that if all of the world’s people used resources at the same rate as Londoners do, it would take at least three more planet Earths to meet their needs. Question: How would you apply the three principles of sustainability (see back cover) to lessen some of these impacts?

GOODNEWS

ConCEPT 22-2 595

pollution is produced in a smaller area and cannot be dispersed and diluted as readily as pollution produced in rural areas can.

The concentration of transportation vehicles and industrial facilities in urban centers results in just over two-thirds of the world’s emissions of CO2 from human-related sources. This causes disruption of local and regional portions of the carbon cycle (see Fig- ure 3-19, p. 70). High concentrations of urban air pol-lution also disrupt the nitrogen cycle (see Figure 3-20, p. 71) because of large quantities of nitrogen oxide emissions, which play a key role in the formation of photochemical smog. Also, nitric acid and nitrate emis-sions are major components of acid deposition in urban areas and beyond (see Figure 18-14, p. 477, and Fig- ure 18-15, p. 478). Nitrogen nutrients in urban runoff and in discharges from urban sewage treatment plants can also disrupt the nitrogen cycle in nearby lakes and other bodies of water, and cause excessive eutrophica-tion (see Figure 20-11, p, 537).

In addition, high population densities in urban areas can increase the spread of infectious diseases, especially if adequate drinking water and sewage systems are not available.

Cities Have Excessive Noise. Most urban dwellers are subjected to noise pollution: any unwanted, disturb-ing, or harmful sound that damages, impairs, or inter-feres with hearing, causes stress, hampers concentration and work efficiency, or causes accidents. Noise levels are measured in decibel-A (dbA) sound pressure units that vary with different human activities (Figure 22-10).

Sound pressure becomes damaging at about 85 dbA and painful at around 120 dbA. At 180 dbA, sound can kill. Prolonged exposure to sound levels above 85 dbA can cause permanent hearing damage. Just one-and-a-half minutes of exposure to 110 decibels or more can cause such damage. About one of every eight children and teens in the United States has some per-

manent hearing loss, mostly from listening to music at loud levels.

Cities Affect Local Climates and Cause Light Pollution. On average, cities tend to be warmer, rainier, foggier, and cloudier than suburbs and nearby rural areas. In cities, the enormous amount of heat generated by cars, factories, furnaces, lights, air conditioners, and heat-absorbing dark roofs and streets creates an urban heat island that is surrounded by cooler suburban and rural areas. As cities grow and merge (Figure 22-6), their heat islands merge, which can reduce the natural dilution and cleansing of polluted air.

In areas with hot climates, the urban heat island effect puts heat stress on humans and many other organisms. It can also greatly increase dependence on air conditioning for cooling, and it can increase the formation of photochemical smog (see Figures 18-11 and 18-12, p. 475) by speeding up the chemical reac-tions involved in its formation. This in turn increases energy consumption, greenhouse gas emissions, and other forms of air pollution in a vicious circle, or posi-tive feedback loop.

The artificial light created by cities (Figures 22-2, top and 22-4) is a form of light pollution that affects some plant and animal species. For example, some endan-gered sea turtles lay their eggs on beaches at night and require darkness to do so. In addition, each year large numbers of migrating birds, lured off course by the lights of high-rise buildings, fatally collide with these structures. Light pollution also makes it difficult for astronomers and urban dwellers to study and enjoy the night sky.

thinking about disadvantages of urbanization

Which two of the disadvantages discussed here for living in urban areas do you think are the most serious? Explain.

Figure 22-10 This chart lists noise levels of some common sounds (in decibel-A [dbA] sound pressure units). You are being exposed to a sound level high enough to cause permanent hearing damage if a noise requires you to raise your voice to be heard, if a noise causes your ears to ring, or if a noise makes nearby speech seem muffled. Prolonged exposure to lower noise levels and occasional loud sounds may not damage your hearing, but such expo-sure can greatly increase internal stress. Question: How many times per day are your ears subjected to noise levels of 85 dbA or more?

Noise Levels (in dbA)

Permanent damagebegins after 8-hour

exposure

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150

Normalbreathing

Whisper

Quietrural area

Quietroom

Rainfall

Normalconversation

Vacuumcleaner

Averagefactory

Lawnmower

Chainsaw

Rock music

Thunderclap(nearby)

Boomcars

Earphonesat loud level

Air raidsiren

Rifle

85


✓

Life Is a Desperate Struggle for the Urban Poor in Less-Developed Countries Poverty is a way of life for many urban dwellers in less-developed countries. At least 1 billion people live under crowded and unsanitary conditions in cities in these countries (Figure 22-11), and according to a 2006 UN study, that number could reach 1.4 billion by 2020. In sub-Saharan Africa, more than seven of every ten urban residents live in such conditions, according to the UN.

Some of these people live in slums—areas dominated by dilapidated tenements and rooming houses where numerous people might live in a single room (see Fig- ure 6-19, p. 141). Asia’s largest slum, Dharavi, in Mum-bai (Bombay), India, is home to 600,000 people and has one public toilet for every 800 residents.

Other poor people live in squatter settlements and shantytowns on the outskirts of cities. They build shacks from corrugated metal, plastic sheets, scrap wood, card-board, and other scavenged building materials, or they

live in rusted shipping containers and junked cars. Some shantytowns are illegal subdivisions where landowners rent land to the poor without city approval. Others are illegal squatter settlements where people take over unoc-cupied land without the owners’ permission, simply because it is their only option for survival.

Poor people living in shantytowns and squatter settlements or on the streets (Figure 6-21, p. 143) usu-ally lack clean water supplies, sewers, electricity, and roads, and are exposed to severe air and water pollu-tion as well as hazardous wastes from nearby factories. Many of these settlements are in locations especially prone to landslides, flooding, or earthquakes. Some city governments regularly bulldoze squatter shacks and send police to drive illegal settlers out. The people usu-ally move back in within a few days or weeks, or build another shantytown elsewhere.

Governments can address these problems. For example, they can slow the migration from rural to urban areas by improving education, health care, and family planning in the countryside, and by encourag-ing investment in small towns. Governments can also designate land for squatter settlements and supply them with clean water and sanitation, as Curitiba, Brazil, has done (Core Case study). Guaranteeing regular bus service enables workers living in such set-tlements to travel to and from their workplaces.

In Brazil and Peru, governments legally recognize existing slums (favelas) and grant legal titles to the land. They base this on evidence that poor people usually improve their living conditions once they know they have a permanent place to live. They can then become productive working citizens who contribute to tax rev-enues that, in turn, pay for the government programs that assist the poor. In some cases, impoverished people with titles to land have developed their own schools, day care centers, and other such structures for social improvement. Unfortunately, in many of the poor-est countries, extensive government corruption diverts some of the limited funds available to help the poor into the hands of those who need it least.

how wouLd you Vote?

Should squatters living in or near cities in less-developed countries be given title to the land they live on? Cast your vote online at www.cengage.com/login.

■ Case study

Mexico City Mexico City—the world’s second most populous city—is an urban area in crisis. Its 20.5 million residents repre-sent a number roughly equal to the entire population of Australia or the U.S. state of New York. Each year, at least 400,000 new residents arrive.

Mexico City suffers from severe air pollution, close to 50% unemployment, deafening noise, overcrowding,

Figure 22-11 Global outlook: Extreme poverty forces hundreds of millions of people to live in slums and shantytowns, such as this one in Rio de Janeiro, Brazil, with no access to adequate water supplies, sewage disposal, and other vital services.

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ConCEPT 22-2 597

traffic congestion, inadequate public transportation, and a soaring crime rate. More than one-third of its resi-dents live in slums called barrios or in squatter settle-ments that lack running water and electricity.

At least 3 million people in the barrios have no sew-age facilities. As a result, huge amounts of human waste are deposited in gutters, vacant lots, and open ditches every day, attracting armies of rats and swarms of flies. When the winds pick up dried excrement, a fecal snow blankets parts of the city. This bacteria-laden fallout leads to widespread salmonella and hepatitis infections, especially among children.

Mexico City has one of the world’s worst air pollu-tion problems (Figure 22-12) because of a combination of factors: too many cars, polluting factories, a warm, sunny climate and thus more smog, and topographical bad luck. The city sits in a high-elevation, bowl-shaped valley surrounded on three sides by mountains—condi-tions that trap air pollutants at ground level. Breathing its air is said to be roughly equivalent to smoking three packs of cigarettes per day, and respiratory diseases are rampant. (See The Habitable Planet, Video 11 at www.learner.org/resources/series209.html to learn how scientists are measuring air pollution levels in Mexico City.)

The city’s air and water pollution cause an estimated 100,000 premature deaths per year. Writer Carlos Fuen-tes has nicknamed it “Makesicko City.”

Large-scale water withdrawals from the city’s aqui-fer have caused parts of the city to subside by 9 meters

(30 feet) during the last century. Some areas are now subsiding as much as 30 centimeters (1 foot) a year. Mexico City’s growing population increasingly relies on water pumped in from as far away as 150 kilome-ters (93 miles). Large amounts of energy are used to pump this water overland and then uphill 1,000 meters (3,300 feet) to the city.

Progress has been made in solving some of Mexico City’s problems. The percentage of days each year in which air pollution standards are violated has fallen from 50% to 20%. The city government has banned cars in its central zone and requires air pollution controls on all cars made after 1991. It has also phased out use of leaded gasoline and called for old buses, taxis, and delivery trucks to be replaced with vehicles that produce fewer emissions. The city also bought land for use as green space and planted more than 25 million trees to help absorb pollutants. In 2009, the city formed a Waste Commission. It is working to build state-of-the-art waste processing centers that, within a few years, will process as much as 85% of the city’s solid waste through recycling and composting, as well as by burn-ing some of it for energy.

thinking about Mexico City and Curitiba

What are two sustainability strategies used in Curi-tiba, Brazil, (Core Case study) that might be helpful in Mexico City?

Figure 22-12 Photochemical smog in Mexico City, Mexico, is caused by cars and factories that generate pollutants and by the city’s location within a bowl-shaped valley that traps emissions, causing them to accumulate to danger-ous levels.

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22-3 How Does Transportation Affect Urban Environmental Impacts?

ConCept 22-3 in some countries, many people live in widely dispersed urban areas and depend mostly on motor vehicles for their transportation, which greatly expands their ecological footprints.

▲

Cities Can Grow Outward or Upward If a city cannot spread outward, it must grow verti-cally—upward and downward (below ground)—so that it occupies a small land area with a high population density. Most people living in compact cities such as Hong Kong, China, and Tokyo, Japan, get around by walking, biking, or using mass transit such as rail or buses. Some high-rise apartment buildings in these Asian cities con-tain everything from grocery stores to fitness centers so their residents do not need to travel for food, entertain-ment, and other services.

In other parts of the world, a combination of plen-tiful land, relatively cheap gasoline, and networks of highways have produced dispersed cities whose residents depend on motor vehicles for most travel (Concept 22-3). Such car-centered cities are found in the United States, Canada, Australia, and other countries where ample land often is available for these cities to expand out-ward. The resulting urban sprawl (Figure 22-7) can have a number of undesirable effects (Figure 22-8).

The United States is a prime example of a car-cen-tered nation. With 4.6% of the world’s people, the United States has almost one-third of the world’s pas-senger cars and commercial vehicles. In its dispersed urban areas, passenger vehicles are used for 98% of all transportation, and three of every four residents drive alone to work every day. Largely because of urban sprawl, all Americans combined drive about the same distance each year as the total distance driven by all other drivers in the world, and in the process use about 43% of the world’s gasoline.

Motor Vehicles Have Advantages and Disadvantages Motor vehicles provide mobility and offer a convenient and comfortable way to get from one place to another. For many people, they are also symbols of power, sex appeal, social status, and success. Much of the world’s economy is also built on producing motor vehicles and supplying fuel, roads, services, and repairs for them.

Despite their important benefits, motor vehicles have many harmful effects on people and on the envi-ronment. Globally, automobile accidents kill approxi-mately 1.2 million people a year—an average of 3,300

deaths per day—and injure another 15 million people. They also kill about 50 million wild animals and family pets every year.

In the United States, motor vehicle accidents kill more than 40,000 people per year and injure another 5 million, at least 300,000 of them severely. Car accidents have killed more Americans than have all the wars in the country’s history.

Motor vehicles are the world’s largest source of out-door air pollution, which causes 30,000–60,000 prema-ture deaths per year in the United States, according to the Environmental Protection Agency. They are also the fastest-growing source of climate-changing CO2 emis-sions. In addition, they account for two-thirds of the oil used (mostly in the form of gasoline) in the United States and one-third of the world’s oil consumption.

Motor vehicles have helped create urban sprawl and the car commuter culture. At least a third of the world’s urban land and half of that in the United States is devoted to roads, parking lots, gasoline stations, and other automobile-related uses. This prompted urban expert Lewis Mumford to suggest that the U.S. national flower should be the concrete cloverleaf (Fig-ure 22-13).

Another problem is congestion. If current trends continue, U.S. motorists will spend an average of 2 years of their lives in traffic jams, as streets and freeways often resemble parking lots. According to a 2008 report by the American Society of Civil Engineers, about 45% of all major urban U.S. highways are regularly congested. Traffic congestion in some cities in less-developed coun-tries is much worse. Building more roads may not be the answer. Many analysts agree with economist Rob-ert Samuelson that “the number of cars expands to fill available concrete.”

Reducing Automobile Use Is Not Easy, but It Can Be Done Some environmental scientists and economists suggest that we can reduce the harmful effects of automobile use by making drivers pay directly for most of the envi-ronmental and health costs caused by their automobile use—a user-pays approach, based on honest environ-mental accounting.

One way to phase in such full-cost pricing would be to charge a tax or fee on gasoline to cover the estimated

harmful costs of driving. According to a study by the International Center for Technology Assessment, such a tax would amount to about $3.18 per liter ($12 per gallon) of gasoline in the United States (see Chapter 16, p. 402). Gradually phasing in such a tax, as has been done in many European nations, would spur the use of more energy-efficient motor vehicles and mass transit, decrease dependence on imported oil, and thus increase economic and national security. It would also reduce pollution and environmental degradation and help to slow projected climate change.

researCh Frontier

Determining the full costs of using gasoline and how to include such costs in its market price; see www.cengage .com/login.

Proponents of this approach urge governments to do two major things. First, fund programs to educate peo-ple about the hidden costs they are paying for gasoline. Second, use gasoline tax revenues to help finance mass transit systems, bike lanes, and sidewalks as alternatives to cars, and reduce taxes on income, wages, and wealth to offset the increased taxes on gasoline. Such a tax shift would help to make higher gasoline taxes more politi-cally and economically acceptable.

Europe, Japan, Singapore, and China have all devel-oped rapid mass transit systems within and between urban areas, as well as networks of sidewalks and bike lanes in many urban and suburban areas. Analysts warn that countries such as the United States that lag behind in developing such systems will face great difficulties

in dealing with the projected decline in oil production and with rapidly rising oil and gasoline prices. The end result could be a sharp decline for suburban housing and shopping centers as they become environmentally and economically unsustainable. As noted earlier in this chapter, there is some evidence that this is beginning to happen already in some U.S. suburban areas.

Taxing gasoline heavily would be difficult in the United States, for three reasons. First, it faces strong opposition from two groups. One group is made up of those people who feel they are already overtaxed, many of whom are largely unaware of the huge hidden costs they are paying for gasoline. The other group is made up of the powerful transportation-related industries such as carmakers, oil and tire companies, road builders, and many real estate developers.

Second, the dispersed nature of most U.S. urban areas makes people dependent on cars. Third, fast, efficient, reliable, and affordable mass transit options, bike lanes, and sidewalks are not widely available in the United States. These factors make it politically difficult to raise gasoline taxes. But U.S. taxpayers might accept sharp increases in gasoline taxes if a tax shift were employed, as mentioned above.

Another way to reduce automobile use and urban congestion is to raise parking fees and charge tolls on roads, tunnels, and bridges leading into cities—espe-cially during peak traffic times. Densely populated Sin-gapore is rarely congested because it auctions the rights to buy a car, and its cars carry electronic sensors that automatically charge the drivers a fee every time they enter the city. Several European cities have also imposed stiff fees for motor vehicles entering their central cities.

Figure 22-13 Concrete cloverleafs like this tangled network of thruways in the U.S. city of Los Angeles, California, are found in most of the world’s increasingly car-dependent cities.

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ConCEPT 22-3 599


Examples include London, England, Stockholm, Swe-den, and Milan, Italy.

Paris, France, which has some of Europe’s worst traf-fic congestion, has upgraded its mass transit system and created express lanes for buses and bicycles on main thoroughfares, while reducing the lanes available for cars. The city also established a program that provides almost 21,000 bikes for rent at 1,450 rental stations throughout the city at a cost of just over $1 a day. Sadly, within two years 80% of the bikes had been stolen or vandalized and had to be replaced at great cost. Portland, Oregon, also had to abandon its bike-sharing program because of theft and vandalism. However, the U.S. city of Boston, Massachusetts, plans to start such a program.

In Germany, Austria, Italy, Switzerland, and the Netherlands, more than 300 cities have car-sharing networks (see the Case Study that follows). Members reserve a car in advance or call the network and are directed to the closest car. They are billed monthly for the time they use a car and the distance they travel. In Berlin, Germany, car sharing has cut car ownership by 75%. According to the Worldwatch Institute, car sharing in Europe has reduced the average driver’s CO2 emis-sions by 40–50%. Car-share companies have sprouted up in the United States in cities such as Madison, Wis-consin, Portland, Oregon, New York, New York, and Los Angeles, California, among others.

■ Case study

Zipcars In 1999, Robin Chase and Antje Danielson, two entre-preneurs living in Cambridge, Massachusetts (USA) recognized a need among city dwellers who were tired of paying high rates for parking, insurance, and other costs of owning a car. In cities with extensive mass tran-sit systems such as New York, New York, and Boston, Massachusetts, a car amounts to a significant expense because of these high costs and because the mass transit option would allow almost anyone to get along without a car much of the time. So why pay the high costs for a car that you may only use occasionally?

To Chase and Danielson, the answer was: don’t pay those costs; instead, join a car-sharing network and pay a much lower price for the convenience of having a car when you need it, renting it by the hour. The two women formed Zipcar, a network whose membership has doubled almost every year since 1999. In 2009, its 325,000 members in the United States were sharing 6,500 cars (10–15% of them hybrid cars).

To become a Zipster, as the members call themselves, you pay a small application charge and an annual $50 fee. In cities where they are available, members can rent a Zipcar for $6 to $10 per hour, which includes the costs of gas, insurance, and maintenance. They make reservations online and are told where to go to pick up the car. A membership card unlocks the vehicle. When finished with the car, the member returns it to where it

was picked it up, and charges for the use of the vehicle are applied to the member’s credit card.

Traveling cleaning crews (many of them college stu-dents) clean the cars once each week. Members agree to keep the cars clean and not to smoke or allow dogs to damage the cars. The system seems to work, as Zipcars are always booked.

Now, several businesses, including Google, ask their employees to use Zipcars for daily business trips in and around the cities where they work. The company’s president estimates that car sharing costs the company about a third of the cost of keeping company cars and reimbursing employees for using their own cars.

thinking aboutCar sharing

If you are or someday might be a car owner living in a city where car-sharing is available, would you consider selling your car and joining a car-sharing network? Explain.

Some Cities Promote Alternatives to Cars Mayors and urban planners in many parts of the world are beginning to rethink the role of the car in urban transportation systems and are providing a mix of other options, as they have in Curitiba, Brazil (Core Case study). Leaders in less-developed countries are recognizing that most of their people could never afford to own automobiles, and they are questioning the development of expensive car-oriented systems that mostly benefit the affluent minority of their citizens.

There are several alternatives to motor vehicles, each with its own advantages and disadvantages. One widely used alternative is the bicycle (Figure 22-14). Bicycles reduce congestion, promote physical fitness, emit no CO2 or other air pollutants, cost little to buy and operate, and reduce the need for parking space. Each year, the number of bicycles produced globally is about 2.5 times the number of cars produced. There is also a growing use of electric bicycles.

Bicycling and walking account for about a third of all urban trips in the Netherlands and in Copenhagen, Denmark. By contrast, bicycles account for only about 1% of urban trips in the United States. But one of five Americans say they would bicycle to work if safe bike lanes were available and if their employers provided secure bike storage and showers at work. There is a growing complete streets movement in the United States that is devoted to making city streets as useful and safe for bicyclists and pedestrians as they are for cars and trucks.

thinking about bicycles

Do you, or would you, use a conventional or an electric bicycle to go to and from work or school? Explain.

Heavy-rail systems (subways, elevated railways, and metro trains) and light-rail systems (streetcars, trolley cars, and tramways) have their advantages and disad-vantages (Figure 22-15). At one time, all major U.S. cities had effective light-rail systems, but they were dis-mantled to promote car and bus use (see Case Study, p. S10, in Supplement 3). However, such systems are being built again in several U.S. cities. An outstanding

example is the light-rail system in Minneapolis, Minne-sota, which opened in 2005 and surprised planners by drawing 50% more riders than they had expected.

The rail system in Hong Kong, China, is one of the world’s most successful, primarily because the city is densely populated and thus half its population can walk to a subway station within 5 minutes. Owning a car is also extremely expensive in this crowded city, which helps to make the rail system attractive to almost everyone.

Buses are the most widely used form of mass transit within urban areas worldwide, mainly because they have more advantages than disadvantages (Figure 22-16). Curitiba, Brazil, has one of the world’s best bus rapid transit systems, which carries tens of thousands of pas-sengers a day (Core Case study, Figure 22-1). But the system is now feeling the strain of pop-ulation pressures, and car use is increasing in Curitiba. Transportation officials there are considering building a light-rail system to help carry the rapidly growing pas-senger load.

Similar bus rapid transit systems have been devel-oped in Bogotá, Colombia, and are being planned for cities such as Mexico City, Mexico; Jakarta, Indonesia; Seoul, South Korea; Beijing and 20 other cities in China; Ottawa and Toronto in Canada; and the U.S. cities of Los Angeles, California; Minneapolis, Minnesota; and Las Vegas, Nevada.

A rapid-rail system between urban areas is another option for reducing the use of cars. In western Europe and Japan, high-speed bullet trains travel between cit-ies at up to 306 kilometers (190 miles) per hour. Such trains began operating in Japan in 1964 and now carry almost a million passengers a day. Since 1964, there has not been a single casualty, and late arrivals average only 6 seconds, explaining why some analysts consider this system to be one of the new wonders of the world.

Figure 22-14 Bicycle use has advantages and disadvantages. The key to increasing bicycle use is the creation of bicycle-friendly sys-tems, including bike lanes. Some cities actually provide bicycles that people can rent at a very low cost. In addition, Japan and the Netherlands strive to integrate the use of bicycles and commuter rail by providing secure bicycle parking at rail stations. Question: Which single advantage and which single disadvantage do you think are the most important?

Provide little protection in an accident

Provide no protection from bad weather

Are impractical for long trips

Secure bike parking not yet widespread

Are quiet and non-polluting

Take few resources to make

Burn no fossil fuels

Require little parking space

Advantages Disadvantages

Bicycles

Trade-Offs

Figure 22-15 Mass transit rail systems in urban areas have advan-tages and disadvantages. Question: Which single advantage and which single disadvantage do you think are the most important?

Expensive to build and maintain

Cost-effective only along a densely populated corridor

Commits riders to transportation schedules


Uses less energy and produces less air pollution than cars do

Use less land than roads and parking lots use

Causes fewer injuries and deaths than cars

Mass Transit Rail

Trade-Offs

Can lose money because they require affordable fares

Can get caught in traffic and add to noise and pollution

Commit riders to transportation schedules

Reduce car use and air pollution

Can be rerouted as needed

Cheaper than heavy-rail system


Buses

Trade-Offs

Figure 22-16 Bus rapid transit systems (where several buses run-ning in express lanes can be coupled together) and conventional bus systems in urban areas have advantages and disadvantages. Question: Which single advantage and which single disadvantage do you think are the most important?

ConCEPT 22-3 601


✓

Figure 22-17 lists the major advantages and disad-vantages of such rapid-rail systems.

In the United States, nearly half of all households have no reasonable access to bus or train service, accord-ing to the American Society of Civil Engineers. But a high-speed bullet train network could replace airplanes, buses, and private cars for most medium-distance travel between major American cities (Figure 22-18). Some planners call for placing high-speed train tracks along interstate freeways, as the federal government already owns the roads and adjacent rights-of-way. These estab-lished transportation corridors could also be used for a new electric grid system, which could provide a more fuel-efficient means to run the trains.

Six Middle Eastern nations—Saudi Arabia, Bahrain, Kuwait, Oman, Qatar, and the United Arab Emirates—plan to spend more than $100 billion to build a modern railway network that will link them together. China has the world’s fastest bullet train, and by 2010, will have completed a vast network of 42 high-speed train routes throughout the country, which is roughly the same size as the United States. One major goal of China’s leaders is to make the country more economically competitive by providing fast and energy-efficient transportation among its major cities.

In the United States, planners have been talking about building high-speed trains for decades, but plans have been slow to materialize. As of 2014, there will likely be only one such train running on a line between Tampa and Orlando, Florida. However, in 2010, the U.S. government began planning for 12 other high-speed rail corridors in various locations around the country. Part of the reason for the delay in building rapid-rail systems in the United States is that revenues from gasoline taxes have been used mostly to build highways at the expense of mass transit.

ConneCtionswind Farms and high-speed trains

Ever ride on a wind train? Americans could get that oppor-tunity if the visions of some planners become reality. A few railroad companies are exploring the idea of powering cross-country trains with electricity from wind farms, most of which are already located in the right places for such a plan. Wind trains would be highly efficient with little or no emis-sions of greenhouse gases or other air pollutants.

how wouLd you Vote?

Should the United States (or the country where you live) develop rapid-rail systems to connect some of its urban areas, even though this will be quite costly? Cast your vote online at www.cengage.com/login.

Figure 22-17 Rapid-rail systems between urban areas have advan-tages and disadvantages. Western Europe and Japan have high-speed bullet trains that travel between cities at up to 306 kilometers (190 miles) per hour. Question: Which single advantage and which single disadvantage do you think are the most important?

Costly to run and maintain

Causes noise and vibration for nearby residents

Adds some risk of collision at car crossings

Much more energy efficient per rider than cars and planes are

Less air pollution than cars and planes

Can reduce need for air travel, cars, roads, and parking areas


Rapid Rail

Trade-Offs

Figure 22-18 solutions: Some potential routes for high-speed bullet trains in the United States and parts of Canada are shown here. Such a system would allow rapid, comfortable, safe, and affordable travel between major cities in a region. It would greatly reduce dependence on cars, buses, and airplanes for trips between these urban areas and would also decrease greenhouse gas emissions and other forms of air pollution. Question: Why do you think such a system has not been developed in the United States? (Data from High Speed Rail Association, U.S. Depart-ment of Transportation, Amtrak)

22-4 How Important Is Urban Land-Use Planning?

ConCept 22-4 urban land-use planning can help to reduce uncontrolled sprawl and slow the resulting degradation of air, water, land, biodiversity, and other natural resources.

▲

Conventional Land-Use Planning Most urban and some rural areas use various forms of landuse planning to determine the best present and future use of each parcel of land.

Land-use planning has often encouraged future population growth and economic development, regard-less of its environmental and social consequences. This typically has led to uncontrolled or poorly controlled urban growth and sprawl.

A major reason for this often-destructive process in the United States and in some other countries is heavy reliance on property taxes levied on all buildings and land parcels based on their economic value. In the United States, 90% of the revenue used by local governments to provide public services, such as schools, police and fire protection, and water and sewer systems, comes from property taxes. As a result, local governments often raise money by promoting urban growth, because they usually cannot raise property tax rates enough on existing properties to meet expanding needs.

Once a land-use plan is developed, governments control the uses of various parcels of land by legal and economic methods. The most widely used approach is zoning, in which various parcels of land are desig-nated for certain uses such as residential, commercial, or mixed use. However, zoning can be used to control growth and protect areas from certain types of devel-opment. For example, cities such as Portland, Ore-gon (USA), and Curitiba, Brazil, (Core Case study) have used zoning to encourage high-density development along major mass transit corridors and to reduce automobile use and air pollution.

Despite its usefulness, zoning has several draw-backs. One problem is that some developers can influ-ence or modify zoning decisions in ways that threaten or destroy wetlands, prime cropland, forested areas, and open space. Another problem is that zoning often favors high-priced housing, factories, hotels, and other busi-nesses over protecting environmentally sensitive areas and providing low-cost housing, again because most local governments depend on property taxes for their revenue.

thinking about Property taxes

What alternatives to depending on property taxes for revenue do local governments have? Which, if any, of these alterna-tives would you support? Explain.

In addition, overly strict zoning can discourage innovative approaches to solving urban problems. For example, the pattern in the United States and in some other countries has been to prohibit businesses in resi-dential areas, which increases suburban sprawl. Some urban planners want to return to mixed-use zoning to help reduce this problem. In the 1970s, Portland, Ore-gon, managed to cut driving and gasoline consumption by resurrecting the idea of neighborhood grocery stores (see Case Study, p. 604).

Smart Growth Works Smart growth is one way to encourage more envi-ronmentally sustainable development that requires less dependence on cars, controls and directs sprawl, and reduces wasteful resource use (see Case Study, p. 604). It recognizes that urban growth will occur, but at the same time, it uses zoning laws and other tools to channel that growth into areas where it can cause less harm.

Smart growth can discourage sprawl, reduce traffic, protect ecologically sensitive and important lands and waterways, and develop neighborhoods that are more enjoyable places in which to live. Figure 22-19 (p. 604) lists popular smart growth tools that we can use to pre-vent and control urban growth and sprawl.

Curitiba, Brazil, (Core Case study) has also used a variety of such strategies to control sprawl and reduce dependence on the car. Several stud-ies have shown that most forms of smart growth pro-vide more jobs and spur more economic renewal than does conventional economic growth. (See The Habit-able Planet, Video 5, at www.learner.org/resources/series209.html to learn the use of smart growth for controlling population growth and urban sprawl in Cape Cod, Massachusetts [USA].)

China has taken the strongest stand of any country against urban sprawl. The government has designated 80% of the country’s arable land as fundamental land. Building on such land requires approval from local and provincial governments and from the State Council, the central government’s chief administrative body. This is somewhat like having to get congressional approval for a new subdivision in the United States. However, China’s approach goes to an extreme; developers violat-ing the rules can face the death penalty.

Many European countries have been successful in discouraging urban sprawl in favor of compact cities.

ConCEPT 22-4 603


They have controlled development at the national level and imposed high gasoline taxes to discourage car use and to encourage people to live closer to workplaces and shops. High taxes on heating fuel encourage peo-ple to live in apartments and small houses. These gov-ernments have used most of the resulting gasoline and heating fuel tax revenues to develop efficient train and other mass transit systems within and between cities.

■ Case study

Smart Growth in Portland, OregonThe U.S. city of Portland, Oregon, has used smart growth strategies to control sprawl and reduce dependence on automobiles. Since 1975, Portland’s population has grown by about 50%, but its urban area has expanded

by only 2%. In addition, abundant green space and nat-ural beauty is just 20 minutes from downtown.

The city has built an efficient light-rail and bus sys-tem that carries 45% of all commuters to downtown jobs—a much higher percentage than in most U.S. cit-ies. By reducing traffic, Portland was able to convert a former expressway and huge parking lot into a water-front park.

Portland encourages clustered, mixed-use neighbor-hood development, with stores, light industries, profes-sional offices, high-density housing, and access to mass transit, which allows most people to meet their daily needs without a car. In addition to its excellent light-rail and bus lines, Portland has further reduced car use by developing an extensive network of bike lanes and walk-ways. Employers are encouraged to give their employ-ees bus passes instead of providing parking spaces.

Since 1975, the city’s air pollution has decreased by 86%. Portland is frequently cited as one of the most livable cities in the United States and in 2008, environ-mental researcher and writer Elizabeth Svoboda ranked it as the greenest city in the United States. In order, the next nine greenest U.S. cities were San Francisco, California; Boston, Massachusetts; Oakland, California; Eugene, Oregon; Cambridge, Massachusetts; Berkeley, California; Chicago, Illinois; Austin, Texas; and Minne-apolis, Minnesota.

thinking about Portland and Curitiba

How is the urban strategy of Portland, Oregon, simi-lar to that of Curitiba, Brazil (Core Case study)? How do their strategies differ?

Preserving and Using Open Space One way to preserve open space outside a city is to draw an urban growth line around each community and to allow no urban development outside that boundary. This urban growth boundary approach is used in the U.S. states of Oregon, Washington, and Tennessee. However, the Seattle region of Washington State found that using a growth boundary to increase housing densities inside the line had the unintended effect of encouraging low-density housing and sprawl in rural and natural areas just beyond the boundary.

Another approach is to surround a large city with a greenbelt—an open area reserved for recreation, sus-tainable forestry, or other nondestructive uses. Satellite towns are often built outside these greenbelts. Ideally, the outlying towns are self-contained, not sprawling, and are linked to the central city by a public transport system that does minimal damage to the greenbelt.

Many cities in western Europe and the Canadian cit-ies of Toronto and Vancouver have used this approach. By establishing a greenbelt outside its urban growth boundary, Seattle, Washington, could have minimized urban sprawl just beyond that line. Greenbelt areas can

Limits and Regulations

Limit building permits

Draw urban growth boundaries

Create greenbelts around cities

ZoningPromote mixed use of housing and small businesses

Concentrate development along mass transportation routes

PlanningEcological land-use planning

Environmental impact analysis

Integrated regional planning

Protection

Preserve open space

Buy new open space

Prohibit certain types of development

Taxes

Tax land, not buildings

Tax land on value of actual use instead of on highest value as developed land

Tax Breaks

For owners agreeing not to allow certain types of development

For cleaning up and developing abandoned urban sites

Revitalization and New Growth

Revitalize existing towns and cities

Build well-planned new towns and villages within cities

Smart Growth Tools

Solutions

Figure 22-19 We can use these smart growth or new urbanism tools to prevent and control urban growth and sprawl. Questions: Which five of these tools do you think would be the best methods for preventing or controlling urban sprawl? Which, if any, of these tools are used in your community?

provide vital ecological services such as absorption of CO2 and other air pollutants, which can make urban air more breathable and help to cut a city’s contribution to projected climate disruption.

A more traditional way to preserve large blocks of open space is to create municipal parks. Examples of large urban parks in the United States are Central Park in New York City (Figure 22-20); Golden Gate Park in San Francisco, California; and Grant Park in Chicago, Illinois.

In 1883, officials in the U.S. city of Minneapolis, Minnesota, vowed to create “the finest and most beau-tiful system of public parks and boulevards of any city in America.” In the eyes of many, this goal has been achieved. Today, the city has 170 parks strategically located so that most homes in Minneapolis are within six blocks of a green space. Similarly, Jacksonville, Florida (USA), has a high ratio of parkland to total city area.

Figure 22-20 With almost 344 hectares (850 acres) that include woodlands, lawns, and small lakes and ponds, New York City’s Central Park is a dramatic example of a large open space in the center of a major urban area.

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22-5 How Can Cities Become More Sustainable and Livable?

ConCept 22-5 an ecocity allows people to choose walking, biking, or mass transit for most transportation needs; to recycle or reuse most of their wastes; to grow much of their food; and to protect biodiversity by preserving surrounding land.

▲

New Urbanism Is Growing Since World War II, the typical approach to suburban housing development in the United States has been to bulldoze a tract of woods or farmland and build rows of houses on standard-size lots (Figure 22-21, middle, p. 606). Many of these developments and their streets, with names like Oak Lane, Cedar Drive, Pheasant Run, and Fox Valley, are named after the trees and wildlife they displaced.

In recent years, builders have increasingly used a pattern known as cluster development, in which high- density housing units are concentrated on one portion

of a parcel, and the rest of the land (often 30–50%) is used as commonly shared open space (Figure 22-21, bottom). When this is done properly, residents can enjoy more open and recreational space within aesthet-ically pleasing surroundings. They might also see lower heating and cooling costs because some walls are shared in multiple-family dwellings. Developers can also cut their costs for site preparation, roads, utilities, and other forms of infrastructure.

Some communities are going further and using the goals of new urbanism, which is a modern form of what could be called old villageism, to develop entire villages

ConCEPT 22-5 605


and promote mixed-use neighborhoods within existing cities. These goals include:

• walkability, with most stores and recreational activi-ties within a 10-minute walk of any home.

• mixed-use and diversity, which provides a blend of pedestrian-friendly shops, offices, apartments, and homes to encourage people of different ages, classes, cultures, and races to move into the villages.

• quality urban design, emphasizing beauty, aesthetics, and architectural diversity.

• environmental sustainability based on development with minimal environmental impact.

• smart transportation, with well-designed train and bus systems connecting neighborhoods, towns, and cities.

A prominent example of new urbanism is a new sub-urb of Freiburg, Germany, called Vauban (see the Case Study that follows). Examples of new urban villages in the United States are Mayfaire, in Wilmington, North Carolina; Mizner Place in Boca Raton, Florida; Middle-

ton Hills near Madison, Wisconsin; Yardley, Pennsyl-vania; Kentlands in Gaithersberg, Maryland; Valencia, California (near Los Angeles); and Stapleton, Colorado (built on an old airport site in Denver).

researCh Frontier

Evaluating, improving, and implementing more environmen-tally sustainable new urbanism; see www.cengage.com/ login.

thinking about new urbanism

Is there an example of new urbanism in or near the place where you live? Would you like to live in such a village? Explain.

■ Case study

The New Urban Village of VaubanSince the early 1990s, the city of Freiburg, Germany, has given high priority to controlling urban sprawl. As part of that effort, the city planned a new suburb called Vauban, completed in 2006 and designed to be virtually free of cars.

A small minority of homeowners in Vauban have cars. Street parking, driveways, and garages are gen-erally forbidden in the village. Car owners have two places to park—two large garages on different sides of town—and a parking space costs $40,000.

Vauban is designed so that each of its 5,000 homes is located within easy walking distance of train lines that connect to surrounding communities. Stores, banks, res-taurants, and schools are also within walking distance of all homes. The town has numerous bike paths and a car-sharing club. Mass transit allows residents to work or shop in Freiburg, a city of about 200,000 people.

The community has no single-family homes. People live in stylish row houses within four- and five-story buildings that were designed with an emphasis on use of passive solar energy (Figure 16-11, left, p. 409). The shared walls between these homes help them to be highly energy-efficient. In addition, 65% of the energy used for electricity and heating in Vauban comes from solar power or from an efficient central cogeneration plant that runs on wood chips and provides central heating and electric power for Vauban residents. Vau-ban’s planners and designers hope that some of the best features of this urban ecovillage will be widely used in other planned communities around the world.

thinking about Vauban and Curitiba

What are two differences between Curitiba, Brazil, and Vauban, Germany, in terms of how each is trying to be more sustainable? Which model do you think would work better for the community in which you live or go to school?

Figure 22-21 These models compare a conventional housing devel-opment (middle) with a cluster housing development (bottom). With a cluster development, houses, town houses, condominiums, and two- to six-story apartments are built on part of the tract. The rest, typically 30–50% of the area, is left as open space for wildlife pre-serves, parks, and walking and cycling paths.

Undeveloped land

Marsh

Pond

Creek

Cluster

Cluster

Typical housing development

Cluster housing development

Creek

The Ecocity Concept: Cities for People, Not Cars According to most environmentalists and urban plan-ners, the primary problem with large cities is not urban growth but our failure to make them more sustainable and livable. These same environmentalists and planners call for us to make new and existing urban areas more self-reliant, sustainable, and enjoyable places to live through good ecological design. (See the Guest Essay on this topic by David Orr on the website for this chapter.)

New urbanism is a step in the right direction, but we can go further by creating more environmentally sustainable cities, called ecocities or green cities, which emphasize the following goals built around the three principles of sustainability (See back cover):

• Use solar and other locally available, renew-able energy resources, and design buildings to be heated and cooled as much as possible by natural means.

• Build and redesign cities for people, not for cars.

• Use energy and matter resources efficiently.

• Prevent pollution and reduce waste.

• Reuse, recycle, and compost 60–85% of all munici-pal solid waste.

• Protect and encourage biodiversity by preserving undeveloped land and protecting and restoring natural systems and wetlands in and around cities.

• Promote urban gardens, farmers markets, and community-supported agriculture.

• Use zoning and other tools to keep urban sprawl at environmentally sustainable levels.

An ecocity is a people-oriented city, not a car-ori-ented city. Its residents are able to walk, bike, or use low-polluting mass transit for most of their travel. Trees and plants adapted to the local climate and soils are planted throughout the city to provide shade, beauty, and wildlife habitats, and to reduce air pollution, noise, and soil erosion. Small organic gardens and a variety of plants adapted to local climate conditions often replace monoculture grass lawns.

An ecocity’s buildings, vehicles, and appliances meet high energy-efficiency standards. Some planners suggest that ecocities could evolve to become energy-indepen-dent. They see homes and businesses containing their own power plants, with solar panels and wind turbines on many roofs providing power to the buildings. These home power plants could also be used to recharge plug-in hybrid cars (Figure 16-6, right, p. 403) and all-electric vehicles. In addition, food waste and lawn and garden trimmings could be put into digesters to make natural gas for heating and cooking.

In an ecocity, abandoned lots and industrial sites are cleaned up and restored, and put to new uses. For example, in Curitiba, Brazil, (Core Case study) an old gunpowder storage building was con-

verted into a theatre, a foundry into a shopping mall, the old railroad station into a railway museum, and a quarry into an amphitheatre.

In Curitiba and other cities, polluted creeks and rivers have been cleaned up and nearby forests, grass-lands, wetlands, and farms have been preserved. Parks are easily available to everyone. Curitiba also employs a municipal shepherd who tends a flock of sheep, which munch the grass in the parks. Thus, instead of spending money and energy on mowing, the city uses its grass as a resource. Meat and wool from the sheep are peri-odically sold to help the city pay for social programs and the sheep manure is used as organic fertilizer.

In an ecocity, much of the food that people eat comes from nearby organic farms, solar greenhouses, community gardens, and small gardens grown on roof-tops, in yards, and in windows boxes. The UN Food and Agriculture Organization (FAO) has estimated that such urban food production supplies food for about one-fifth of the world’s 3.4 billion urban residents. The FAO proj-ects that with organized programs and financial incen-tives, much more of the world’s food could be grown in or near cities. Experts project that rising oil prices will increase food shipping costs, which could cause a shift from globalized agriculture to more localized food pro-duction in urban areas (Science Focus, p. 608).

Finally, an ecocity provides plenty of educational opportunities for its residents by teaching them about environmental problems and solutions. This includes not only school curricula, but also botanical gardens, humane and sustainable zoos and aquaria, and outdoor learning centers. Curitiba, Brazil (Core Case study), has established Lighthouses of Knowl-edge—free educational centers located strategically around the city. They include libraries, Internet access, job training, and other resources.

This may sound like a futuristic dream, but ecocities are real, as you saw in this chapter’s opening Core Case study. An example of an emerging ecocity is Bogotá, Colombia. Its transformation began in 1998 when Enrique Peñalosa was elected mayor. His major goal was to improve life for the 5.6 million city residents who did not own cars. Within a short time, under his leadership and that of his successor Antanas Mockus, the city built an efficient and widely used bus rapid transit system; established hundreds of kilometers of bicycle lanes and pedestrian-only streets through-out the city; renovated or created 1,200 parks; planted more than 100,000 trees; and encouraged citizens to become involved in improving their local neighbor-hoods. As a result, between 1998 and 2006, rush-hour traffic decreased by 40%, traffic-related deaths dropped by 20%, and Bogotá’s citizens developed a strong sense of civic pride.

Other examples of cities that have attempted to become more environmentally sustainable and liv-able include Waitakere City, New Zealand; Stockholm and Malmo in Sweden; Helsinki, Finland; Vancouver, British Columbia, in Canada; and in the United States,

GOODNEWS

ConCEPT 22-5 607


Portland, Oregon (Case Study, p. 604); Davis, Califor-nia; Olympia, Washington; and Chattanooga, Tennes-see (see Chapter 1, Case Study, p. 25).

The Ecovillage Movement is GrowingAnother innovative approach is the growing global eco-village movement, in which small groups of people come together to design and live in more sustainable villages in rural and suburban areas, and in neighborhoods or “eco-hoods” within cities.

Ecovillagers use diverse methods to live more sus-tainably and to decrease their ecological footprints. Strategies include generating electricity from solar cells, small wind turbines, and small hydropower systems; collecting rainwater; using composting toilets; using solar cookers (see Figure 16-17, p. 412) and rooftop solar collectors to provide hot water; cooperating in the development of organic farming plots; and using passive solar design, energy-efficient houses, and living roofs, as discussed in Chapter 16. In Findhorn, Scotland, resi-dents have reduced their average ecological footprint per person by about 40% by using some of these meth-ods, and other cities claim similar reductions. Another example is Vauban, Germany (see Case Study, p. 606).

One example in the United States is Los Angeles Ecovillage, started in 1993 as a project to show how people in the middle of a sprawling and unsustainable city such as Los Angeles, California, can establish small

pockets of sustainability. It consists of two small apart-ment buildings with about 55 residents and a common courtyard. Working together, its members use solar pan-els to heat much of their hot water. They compost their organic wastes and use the compost in a large courtyard garden that provides vegetables and fruits, and serves as a community commons area for relaxation and social interaction. The ecovillage is within walking distance of subway and bus stops, and members who live without a car pay a lower rent. The group has also established a bicycle repair shop.

Another example of an ecovillage is the BedZED housing development in inner London, England. It was designed to be energy-efficient, built out of local and recycled materials, and is heated and powered by solar cells and by a cogeneration power plant that runs on biomass to generate heat and electricity. It is located near a train station so that residents can get along with-out cars. Residents also harvest rainwater and recycle gray water, or water that is slightly polluted such as dishwater, for gardening and other uses (see Chap- ter 13, pp. 337–338), and they grow vegetables in on-site organic gardens. The average ecological footprint per person in this ecovillage is about 33% smaller than that of London as a whole, and some residents have a 70% smaller footprint per person.

By 2008, there were more than 375 ecovillages, over half of them in Europe and North America. Other examples are found near Ithaca, New York, and Ashe-ville, North Carolina, in the United States; Munksård near Copenhagen, Denmark; Porto Alegre in Brazil;

SCienCe FoCuSUrban Indoor Farming

people. Hydroponic crops would be grown on the upper floors. Chickens (and the eggs they produce) and fish that feed on plant waste would be grown on lower floors.

Nitrogen and other plant nutrients could be extracted from the animal wastes, and perhaps from city sewage treatment plants, and recycled to the plants. Electricity for heat-ing and lighting could be provided by geo-thermal, solar, or wind energy, energy from composted plant and animal wastes, and fuel cells powered by hydrogen produced with the use of renewable energy. Such a system would mimic nature by applying all three principles of sustainability.

Critical thinkingWhat are three ecological advantages and three environmental disadvantages of greatly increasing urban farming? Do you believe that the advantages outweigh the disadvan-tages? Explain.

Scientists are studying various ways to grow more food indoors in urban areas. One method that city dwellers could implement quickly is the use of rooftop greenhouses to provide them with most of their fruits and vegetables. Researchers have found that such greenhouses use as little as 10% of the water and 5% of the area occupied by conventional farms to produce similar yields.

In 2007, Sun Works, a company in New York City (USA) that designs energy-efficient urban greenhouses, built a demonstration greenhouse on a barge floating in the Hud-son River. It used solar power and recycled water to grow vegetables and fruits (see Figure 12-36, p. 311) and is now operated by the nonprofit Groundwork Hudson Valley group as an educational center for thou-sands of annual visitors. In 2008, Sun Works installed a greenhouse on top of a school in the city. It serves as a science teaching area and supplies produce for the school cafeteria. Ted Caplow, executive director of Sun Works,

projects that the rooftops of New York City could provide roughly twice the greenhouse area needed to supply the entire city with fruits and vegetables.

A more far-reaching idea is to use hydro-ponic gardens (see Figure 12-6, p. 282) to provide the water and nutrients to grow fruits and vegetables on glass walls of offices and other buildings. The crops would be grown in small containers in a space between two thick glass panes that make up the wall of a build-ing. Such glass walls would also provide light and passive solar heating during winter. These walls would have automatic shading systems to keep the plants and building interior cool during very hot weather. Vertical conveyor belts would lower the plants for harvesting and replanting on a year-round basis.

Some scientists envision vertical farms in 30-story buildings, each occupying a single city block. Each of these farms could provide vegetables, fruits, chickens, eggs, and fish (grown in aquaculture tanks) for 50,000

Mbam in Senegal, Africa; Sieben Linden in Germany; and Findhorn in Scotland. Ecovillages and ecocities and various individual projects provide us with a labora-tory for improving the ecological design of houses and other buildings (see Case Study that follows), basing such improvements on the three principles of sustainability.

■ Case study

A Living BuildingThere are a growing number of experiments in expand-ing the boundaries of green building and more sustain-able architecture. An example of leading-edge sus-tainable design is the Omega Center for Sustainable Living (OCSL), an award-winning green building at the Omega Institute for Holistic Studies, a nonprofit, edu-cational retreat center in Rhinebeck, New York (USA) (Figure 22-22).

The OCSL is a state-of-the art environmental educa-tion center and a water reclamation facility that cleans and recycles the Omega Institute’s campus wastewater using zero chemicals and zero net energy. The building includes a classroom, a mechanical room, a greenhouse, and constructed wetlands, where people come to learn about innovative solutions to pressing environmen-tal problems. It was designed to achieve Leadership in Energy and Environmental Design (LEED®) Platinum certification, and to be one of the first certified Living Buildings in the United States.

A Living Building is built around the following design goals:

• Take into account the climate, vegetation, and other characteristics of the surrounding ecoregion and keep the building from interfering with those characteristics.

• Make the building capable of using only renewable resources for its energy needs.

• Include a system for capturing, treating, and recy-cling all water used in the building.

• Make the building highly energy efficient and design it to be aesthetically pleasing.

The heart of the OCSL is a large greenhouse contain-ing a water filtration system called the Eco Machine™, based on a design pioneered by John Todd (Figure 20-C, p. 553). This living system uses plants, bacteria, algae, snails, and fungi to recycle Omega campus wastewater into clean water used to restore the aquifer under Omega’s property. The Eco Machine™ reclaims waste-water from toilets, as well as gray water from showers and baths. All water coming through the Eco Machine™ is purified and returned to the aquifer, creating a closed loop hydrological process.

The building is oriented with a southern exposure in order to maximize passive solar performance. It has a long span of windows on its south side, and in- coming heat is stored in the building’s large mass of concrete and in the water within the Eco Machine™. In addition, the building has a geothermal system (based

Urban Indoor Farming

Figure 22-22 In 2009, the Omega Institute opened the doors to the Omega Center for Sustainable Living (OCSL), a pioneering project in sustainable building design. The OCSL is self-sustaining, in that it recycles its wastewater, is heated and cooled by a geothermal system, and generates electricity using panels of solar cells. The building also adds little or no carbon dioxide to the atmosphere.

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on the general design shown in Figure 16-31, p. 425) that cools the building in summer and, with radiant floor heating, supplements the solar gain in winter. The building’s electrical needs are served by solar cells. Also, it has a vegetated green roof system combined with a recycled reflective steel roof to help reduce heat loss during winter and heat gain during summer.

researCh Frontier

Ecocity and ecobuilding design; see www.cengage.com/ login.

Here are this chapter’s three big ideas:

■ Urbanization is increasing steadily and the numbers and sizes of urban areas are growing rapidly, especially in less-developed countries.

■ Most urban areas are unsustainable with their large and growing ecological footprints and high levels of poverty.

■ Urban areas can be made more sustainable and livable just as some cities and villages already are.

Curitiba, Brazil, and Sustainability

In this chapter, we saw that urban areas around the world face numerous challenges largely related to population growth. We know that just in less-developed countries, more than a million people are added to urban areas each week. We have also seen that despite the environmental problems plaguing cities, there are a growing number of inspiring examples of cities and villages around the world that are striving to become more environmen-tally sustainable. While cities can magnify environmental prob-lems, they can also gather people with the energy and imagina-tion needed to solve some of those problems.

Curitiba, Brazil, (Core Case study) is one city in a less- developed country that has made great strides toward becoming environmentally sustainable. Its 3.2 million people have opportunities to live well and improve their lives, and its ecologi-

cal footprint is considerably smaller than that of most cities its size. Curitiba’s story gives us hope for developing more sustain-able cities. The most difficult challenge is to convert cities with little or no hope to cities full of hope, as inspiring and innovative leaders have done for Curitiba and Bogotá, Colombia.

Curitiba and other ecocities and ecovillages apply the prin-ciples of sustainability in their efforts to become more sustain-able urban areas. People in these communities rely more on solar energy for growing food and providing power than do people in more conventional cities. They also reuse and recycle resources much more frequently and systematically, as nature recycles nu-trients. In preserving and using green spaces, these cities and vil-lages value and preserve biodiversity and use it to enhance their own health and well-being.

r e V i s i t i n g

A sustainable world will be powered by the sun; constructed from materials that circulate repeatedly; made mobile by trains, buses, and bicycles;

populated at sustainable levels; and centered around just, equitable, and tight-knit communities.

Gary GardnEr

Review

1. Review the Key Questions and Concepts for this chapter on p. 587. Describe how Curitiba, Brazil, has attempted to become a more sustainable city (Core Case study).

2. Distinguish between urbanization and urban growth. Describe two factors that increase the population of a city.

3. List four global trends in urban growth. Describe four phases of urban growth in the United States.

4. What is urban sprawl? List five factors that have promoted urban sprawl in the United States. List five undesirable effects of urban sprawl.

5. What are four advantages of urbanization? What are six disadvantages of urbanization? What is noise pollution and how can we reduce it? Explain why most cities and urban areas are not sustainable.

CRitiCal thinKing

6. Describe some of the problems faced by poor people who live in urban areas. How can governments help to reduce these problems? Describe the urban problems of Mexico City, Mexico.

7. Distinguish between compact and dispersed cities, and give an example of each. What are the major advantages and disadvantages of motor vehicles? List four ways to reduce dependence on motor vehicles. Describe the major advan-tages and disadvantages of relying more on (a) bicycles, (b) mass transit rail systems, (c) bus rapid transit systems within urban areas, and (d) rapid-rail systems between urban areas.

8. What is landuse planning? What is zoning and what are its limitations? What is smart growth? List five tools used to promote smart growth. Describe strategies used by the U.S. city of Portland, Oregon, to help control urban sprawl and reduce dependence on automobiles. What are three ways to preserve open spaces around a city?

9. What are new urbanism’s five key goals and why is Vauban, Germany, a good example of it? What is cluster development? List eight goals of ecocity and ecovillage design. Summarize the scientific exploration of urban indoor farming. Describe three strategies used within ecovillages to make their neighborhoods more sustain-able. Describe an example of a highly sustainable living building.

10. Explain how people in Curitiba, Brazil, (Core Case study) have applied each of the three prin-ciples of sustainability to make their city more sustainable.

Note: Key terms are in bold type.

Review

1. Review the Key Questions and Concepts for this chapter on p. 587. Describe how Curitiba, Brazil, has attempted to become a more sustainable city (Core Case study).

2. Distinguish between urbanization and urban growth. Describe two factors that increase the population of a city.

3. List four global trends in urban growth. Describe four phases of urban growth in the United States.

4. What is urban sprawl? List five factors that have promoted urban sprawl in the United States. List five undesirable effects of urban sprawl.

5. What are four advantages of urbanization? What are six disadvantages of urbanization? What is noise pollution and how can we reduce it? Explain why most cities and urban areas are not sustainable.

CRitiCal thinKing

1. Curitiba, Brazil, (Core Case study) has made sig-nificant progress in becoming a more environ-mentally sustainable and desirable place to live. If you live in an urban area, what steps, if any, has your com-munity taken toward becoming more environmentally sustainable?

2. In Curitiba, Brazil, (Core Case study) recycling rates have fallen in recent years, even though they are still among the highest in the world. Former Mayor Jaime Lerner attributes this decline to failure on the part of the city’s leadership to encourage recycling. List five ways in which you think Curitiba, or any city, could encourage residents to recycle.

3. Do you think that urban sprawl is a problem and some-thing that should be controlled? Develop three arguments to support your answer. Compare your arguments with those of your classmates.

4. Write a brief essay that includes at least three reasons why you (a) enjoy living in a large city, (b) would like to live in a large city, or (c) do not wish to live in a large city. Be specific in your reasoning. Compare your essay with those of your classmates.

5. One issue debated at a UN conference was the question of whether housing is a universal right (a position supported by most less-developed countries) or just a need (supported by the United States and several other more-developed countries). What is your position on this issue? Defend your choice.

6. If you own a car or hope to own one, what conditions, if any, would encourage you to rely less on your car and to travel to school or work by bicycle, on foot, by mass transit, or by carpool?

7. Do you believe the United States or the country in which you live should develop a comprehensive and integrated mass transit system over the next 20 years, including an efficient rapid-rail network for travel within and between its major cities? How would you pay for such a system?

8. Consider the goals listed on p. 607 as part of the ecocity concept. How close to reaching each of these goals is the city in which you live or the city nearest to where you live? Pick what you think are the five most important of these goals and describe a way in which that city could meet each of those five goals.

9. Congratulations! You are in charge of the world. List the three most important components of your strategy for dealing with urban growth and sustainability in (a) more-developed countries and (b) less-developed countries.

10. List two questions that you would like to have answered as a result of reading this chapter.

www.CEnGaGEBrain.Com 611


1. Calculate the carbon footprint per car, that is, the number of metric tons (and tons) of CO2 produced by a typical car in one year. Calculate the total carbon footprint for all cars in the city, that is, the number of metric tons (and tons) of CO2 produced by all the cars in one year. (Note: 1 metric ton = 1,000 kilograms = 1.1 tons)

2. If 20% of the people were to use a carpool or to take mass transit in the city instead of driving their cars, how many metric tons (and how many tons) of these CO2 emissions would be eliminated?

3. By what percentage, and by what average distance driven, would use of cars in the city have to be cut in order to reduce by half the carbon footprint calculated in question 1?

eCologiCal FootpRint analySiS

Under normal driving conditions, an internal combustion engine produces approximately 200 grams (0.2 kilograms, or 0.44 pounds) of CO2 per kilometer driven. In one large city,

leaRning online

StUdENt COMPANION SItE Visit this book’s website at www.cengagebrain.com/shop/ISBN/0538735341 and choose Chapter 22 for many study aids and ideas for further reading and research. These include flashcards, practice quiz-zing, Weblinks, information on Green Careers, and InfoTrac® College Edition articles.

For students with access to premium online resources, log on to www.cengage.com/login.

Find the latest news and research, (including videos and podcasts), at the . Visit www.CengageBrain.com for more information.

there are 7 million cars, and each car is driven an average of 20,000 kilometers (12,400 miles) per year.

cities and sustainability - houston independent … 22...22 cities and sustainability the ecocity...

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