Urbanization Building Sustainable Cities Important Questions How is

Urbanization Building Sustainable Cities

Important Questions… � � � How is the world’s population distributed between rural and urban areas and what factors determine how urban areas develop? What are the major resource and environmental problems of urban areas? How do transportation systems shape urban areas and growth and what are the advantages and disadvantages of various forms of transportation? What methods are used for planning and controlling urban growth? How can cities be made more sustainable and more desirable places to live?

Urban Growth People move to cities because “push” factors force them out of rural areas and “pull” factors give them the hope of finding jobs and a better life in the city. � Five “Trends” � › The proportion of the global population living in urban areas is increasing. › The number of large cities is mushrooming. › Urbanization is increasing rapidly in developing countries. › Urban growth is much slower in already heavily urbanized developed countries. › Poverty is becoming increasingly urbanized as more poor people migrate in to urban areas from rural.

MAJOR URBAN AREAS OF THE WORLD Satellite images of the earth at night showing city lights. Currently 49% of the world’s population live in urban areas (2% of earth’s land area).

Urbanization in the U. S. � Most growth has occurred in the South and West. � There have been vast improvements made in the quality of life in cities since 1920. � However, there are still issues: › › Deteriorating services Aging infrastructure Budget crunches Rising poverty

Urban Sprawl � When land is available and affordable, urban areas tend to sprawl outward because: › Federal government loan guarantees stimulated the development of suburbs. › Low-cost gasoline and government funding of highways encourages automobile use. › Tax-laws encourage home ownership. › Most zoning laws separate residential and commercial use of land. › Many urban areas lack proper planning.

URBAN SPRAWL IN ATLANTA Urban sprawl has increased travel time in automobiles, decreased energy efficiency, increased urban flooding problems, destroyed prime cropland forests, and has led to economic decline of major cities.

Natural Capital Degradation Urban Sprawl Land Biodiversity Human Health and Water Aesthetics Increased runoff Loss of cropland Contaminated drinking water Loss of forests and air grasslands Increased surface water & ground water pollution Loss of wetlands Weight gain Loss and fragmentation of wildlife habitats Increased use of surface water and groundwater Noise pollution Increased wildlife roadkill Increased soil erosion Energy, Air, and Climate Economic Effects Increased energy use & waste Higher taxes Increased air pollution Decline of downtown business districts Increased greenhouse gas emissions Decreased storage of surface water and Enhanced global Sky illumination groundwater warming at night Increased flooding Warmer microclimate (urban Traffic congestion Decreased natural heat island effect) sewage treatment Increased unemployment in central city Loss of tax base in central city

Pros and Cons � � � Can offer more job opportunities Better education and health Better savings to governments for services Protect biodiversity by concentrating people Recycling is more feasible � � � Cities are rarely selfsustaining Can threaten biodiversity Lack trees Concentrate pollutants and noise Spread infectious disease Centers of crime and poverty, sometimes terrorism

Noise Pollution � Noise levels of some common sounds. Prolonged exposure to lower noise levels and occasional loud sounds can greatly increase internal stress.

Urban Heat Island Effect

Transportation and Urban Development � Land availability determines whether a city must grow vertically or spread out horizontally and whether it relies mostly on mass transit or the automobile. › If Americans doubled their use of mass transit from 5% to 10%, this would reduce U. S. dependence on oil by 40%. › Motor vehicles provide personal benefits and promote economic growth, but also kill and injure many people, pollute the air, promote urban sprawl, and result in traffic jams. › Although it would not be politically popular, we could reduce reliance on automobiles by having users pay for their harmful effects. US 280 AKA A NIGHTMARE

Solutions: Redesigning Urban Transport Alternatives include walking, bicycling, and taking subways, trains, and buses. � Should half the U. S. gasoline tax be used to develop mass transit, bike lanes, and other alternatives to the car? �

Trade-Offs Bicycles Advantages Affordable Produce no pollution Quiet Require little parking space Easy to maneuver in traffic Take few resources to make Very energy efficient Provide exercise Disadvantages Little protection in an accident Do not protect riders from bad weather Not practical for trips longer than 8 kilometers (5 miles) Can be tiring (except for electric bicycles) Lack of secure bike parking

Trade-Offs Mass Transit Rail Advantages Disadvantages More energy efficient than cars Expensive to build and maintain Produces less air pollution than cars Cost-effective only along a densely populated narrow corridor Requires less land than roads and parking areas for cars Causes fewer injuries and deaths than cars Reduces car congestion in cities Commits riders to transportation schedules Can cause noise and vibration for nearby residents

Trade-Offs Buses Advantages Disadvantages More flexible than rail system Can lose money because they need low fares to attract riders Can be rerouted as needed Cost less to develop and maintain than heavy-rail system Can greatly reduce car use and pollution Often get caught in traffic unless operating in express lanes Commits riders to transportation schedules Noisy

Trade-Offs Rapid Rail Advantages Disadvantages Can reduce travel by car or plane Expensive to run and maintain Ideal for trips of 200– 1, 000 kilometers (120 – 620 miles) Must operate along heavily used routes to be profitable Much more energy efficient per rider over the same distance than a car or plane Causes noise and vibration for nearby residents

The Demise of US Mass Transit � In the early 1900 s, the U. S. had one of the world’s best street car systems. › It was bought and destroyed by companies to sell cars and buses. › At the same time, National City Lines worked to convert electric -powered commuter locomotives to dieselpowered ones.

Solutions: Urban Land-Use Planning and Control Solution s Growth Tools Smart Limits and Regulations • Limit building permits • Urban growth boundaries • Greenbelts around cities • Public review of new development Zoning • Encourage mixed use • Concentrate development along mass transportation routes • Promote high-density cluster housing developments Planning • Ecological land-use planning • Environmental impact analysis • Integrated regional planning • State and national planning Protection • Preserve existing open space • Buy new open space • Buy development rights that prohibit certain types of development on land parcels Taxes • Tax land, not buildings • Tax land on value of actual use (such as forest and agriculture) instead of highest value as developed land Tax Breaks • For owners agreeing legally to not allow certain types of development (conservation easements) • For cleaning up and developing abandoned urban sites (brownfields) Revitalization & New Growth • Revitalize existing towns & cities • Build well-planned new towns and villages within cities

Cluster Development � High density housing units are concentrated on one portion of a parcel with the rest of the land used for commonly shared open space.

The Ecocity Concept � An ecocity allows people to walk, bike, or take mass transit for most of their travel, and it recycles and reuses most of its wastes, grows much of its own food, and protects biodiversity by preserving surrounding land. › Protect biodiversity by preserving, protecting, and restoring surrounding natural areas. › Promote urban gardens and farmers markets. › Build communities that promote cultural and economic diversity. › Use zoning and other tools to keep the human population and environmentally sustainable levels.

The Ecocity Concept � Principles of sustainability: › Build cities for people not cars. › Use renewable energy resources. › Use solar-power living machines and wetlands for waste water treatment. › Depend largely on recycled water. › Use energy and matter efficiently. › Prevent pollution and reduce waste. › Reuse and recycle at least 60% of municipal solid waste. › Promote green design of buildings