Sustainable Cities: Urban Land Use and Management

Definitions Urban (metropolitan) area = town plus its suburbs City = large number of people with a variety of professions who depend on resources from the outside of city boundary Rural area = an area with a population less than 2,500 people Village = group of rural households liked by custom, culture,family ties. Historical utilization of natural resources

Urbanization & Urban growth Degree of urbanization is percentage of population living in area of greater than 2,500 people Urban growth due to: natural increase - births immigration - poor are pulled to urban areas or are pushed from rural areas Trends of urban growth: Increase of 2% to 45% of people in urban areas since 1950 By 2050 about 66% of the world’s people will be living in urban areas.

Urbanization & Urban growth The number of large cities is mushrooming megacities and megalopolis Today, more than 400 cities have over 1 mil. or more people. 19 megacities with over 10 mil. People i.e.Tokyo (28 mil), Mexico City (18 mil), New York (17 mil). Most of growth in developing countries will be urban growth with all of its problems 38% of the people in live in cities. But by 2025 it will be 54%. Many of these cities are already short on water, have waste & pollution problems.

Urbanization & Urban Growth Urban growth is slower in developed countries 75% of the people live in cities. But by 2025 it will be 82%. Poverty is becoming increasingly urbanized slums, squatter settlements and shantytowns at least 1 billion people live in crowed slums of inner cities. No access to water, sewer, electricity, education etc. 100 mil people are homeless & sleep on the streets Case study - Mexico City

Mexico City The world’s second largest city with 18 million people or one in five Mexicans severe air pollution (over 4 million cars) within a valley that causes an estimated 100,000 premature deaths/year high unemployment rate, close to 50% high crime rate over one-third (6 million) of its residents live in slums (barrios) without running water, sewer (but running sewage), or electricity high infection rates i.e. salmonella, hepatitis

United States Urbanization Migration to large central cities Migration from cities to suburbs Migration from north & east to south & west Urban sprawl, growth of low-density development on the edge of cities. Encouraged by: - availability of cheap land, (forests, agriculture fields etc.). - government loans guarantees for new single-family homes - government & state funding of highways - low-cost gasoline encourage car use - low interest mortgage

Major Spatial Patterns Concentric Circle City such as New York Sector City is the large urban area extending from San Frdancisco to San Jose, CA Multiple Nuclei City is Los Angeles Megalopolis is when separate cities join such as the Bowash

Concentric Circle Model Central business district (CBD) Deteriorating transition zone Worker’s homes Middle-class suburbs Commuter's zone

Sector Model High-rent residential Intermediate-rent residential Low-rent residential Education and recreation Transportation Industrial Core (CBD)

Multiple-Nuclei Model CBD Wholesale, light manufacturing Low-rent residential Intermediate-rent residential High-rent residential Heavy manufacturing Outlying business district Residential Suburb Industrial Suburb

Major Urban Problems in U.S. Deteriorating services Aging infrastructures Budget crunches from lost tax revenues as businesses and affluent people leave Rising poverty with violence, drugs, decay Urban sprawl - growth of low-density development on edges of cities and towns 9 consequences of “bad growth”

75% of the US population live in urban areas occupying 3% of the country’s land area

Urban Resources & Environmental Problems 45% of people living in 5% of land – cities – consume 75% of the world’s resources Urban areas depend upon imports Benefits of urbanization: recycling more economically feasible decreased birth rates reduces environmental pressures per capita expenditures on environmental protection high in urban areas population concentration impacts biodiversity less

Urban Resource and Environmental Problems Destruction of plant life - what is $ value? Cities produce little of own food Urban heat island effect --> dust dome 5 ways to counteract this effect Water supply and flooding problems 5 ways to reduce demand on reservoirs and waste treatment systems High pollution exposure

The enormous amount of heat generated creates an urban heat island Additional heat changes climate of surrounding area

Urban Resource & Environmental Problems Excessive noise exposure  health effects Hearing loss, hypertension, muscle tension, migraines, headaches, higher cholesterol levels, gastric ulcers, irritability, insomnia, psychological disorders, aggression

Urban Resource & Environmental Problems Beneficial effects: education social services medical care Harmful effects infectious disease spread high density population inadequate drinking and sewage system physical injuries pollution exposure Urban Sprawl

Impacts of Urban Sprawl Water Land and Biodiversity Human Health and Aesthetics Increased runoff Increased surface water & groundwater pollution Increased use of surface water & groundwater Decreased storage of Surface water & groundwater Increased flooding Decreased natural Sewage treatment Loss of cropland Loss of forests & grasslands Loss of wetlands Loss & fragmentation of wildlife habitats Increased wildlife road kill Increased soil erosion Contaminated drinking water & air Noise pollution Sky illumination at night Traffic congestion

Impacts of Urban Sprawl Energy, Air, and Climate Increased energy use and waste Increased air pollution Increased greenhouse gas Emissions Enhanced global warming Warmer microclimate (heat island effect) Economic Effects Higher taxes Decline of downtown business districts Increased unemployment in central city Loss of tax base in central city

Transportation and Urban Development Determines where people live, where they go to work and buy stuff, how much land is paved and exposure to air pollution Cities grow up if they can’t grow out; more prone to use mass transit Urban sprawl due to cheap gas and land and highways; dispersed car-centered cities use 10x more energy

Motor vehicle concentration Ground transportation: individual (cars, etc) and mass (buses and rail) U.S. has 35% of cars and trucks used for 98% of all urban transportation Motor scooters - effort to change to electric Riding bicycles; less pollution and dangerous and more efficient than walking bicycles available for public use bike and ride systems Drive alone 80% Other 4% Public transit 5% Car pool 11%

Pros and Cons of Mass transit 3% mass transit use in U.S. to 47% in Japan 20% gasoline tax revenues to mass transit Rapid rail, suburban trains and trolley - efficient at high population density High speed rail lines – replace planes, buses and private cars; but require large government subsidies Bus systems more flexible than rail systems but efficient when full