Cities were first established when nomadic people settled around food sources, religious sites, or waterways. Early people soon began to design the arrangement of personal dwellings, religious buildings, food stores, and government centers within their communities along trade routes that linked cities. In the fifth century B.C.E., the “Father of Town Planning,” Greek architect Hippodamus of Miletus, designed towns in a geometric pattern that was not only functional but also had aesthetic balance. Likewise, the Romans arranged residences, temples, and forums in a symmetrical design.

City planning declined after the fall of the Roman Empire only to reemerge during the Renaissance with a revival of Greco-Roman styles. During this time,  the popular design for cities featured concentric circles radiating out from a central point with straight streets connecting the circles, like spokes of a wheel.

European cities such as Venice (Italy), London (England), and Mannheim (Germany) featured this design with wide streets surrounding a public square or government building. A famous example of this circumferential pattern is the extensive redesign of Paris by Baron George Eugène Haussmann in 1848.

In addition to aesthetics, Haussmann took into consideration population density, sanitation, and recreational space.

     In the New World, some cities, specifically New York, were designed in a grid or block pattern which allowed for easy expansion. However, during the Industrial Revolution, this design led to overcrowding, congestion, and a shortage of resources. City planners realized they needed to consider population growth, economics, income opportunities, environmental impact, and transportation when designing a city. With the establishment of

municipal planning commissions, zoning ordinances, and subdivision regulations, city planning became standardized.

Perhaps the most important factor in city planning is predicting population growth. The population of a city will determine its need for housing,  resources such as food and utilities, jobs, schools, hospitals, fire protection,social services and entertainment. Population trends are based on census data, comparisons with other cities’ census data, municipal registrations, statistical models, and current demographics. Variables used in equations to predict population growth include birth and death rates, surviving birth rates, migration out of or into a city, education level and economic level.

The current age of a city’s population is important to know, because young couples are likely to have children who in turn will need schools, whereas a city with mostly retirees may need more healthcare facilities. To avoid overcrowding and dwindling resources, city planners must assess their city’s ability to accommodate a severe influx of new residents or businesses.

       Neighborhood density, or population per square mile, is also a concern.Land area density is based on the design of residential dwelling and the square footage needed per family. Single family dwellings typically house the fewest people. Duplexes, condominiums, tenements, apartment complexes, and high-rise apartment buildings house considerably more. The greater the population density, the greater the need for grocery stores, shopping centers, gas stations, and so on, to accommodate residents. The number of schools an area needs is based on the population of couples at childbearing age. The number of hospitals needed is calculated based on the projected number of patient days per thousand residents. Fire protection and water supply are also based on population.

When preparing new land to be developed, the city planner consults a variety of maps. Land surveys and topography maps denote the elevation and features of the land to scale, whether it is fields, hills, valleys, floodplains, or mountains. An areagraph measures areas in acres on a scale. A hydrograph shows characteristics of water sources. City planners need to calculate a density versus acres proportion to determine how much land should be used for residential, business, and public facilities.

   Depending on land use regulations, planners decide on the orientation of buildings, parking spaces, and streets. Houses can be arranged perpendicular, adjacent, or parallel to streets. The Sun’s orientation throughout the day, based on geographic  latitude, helps the planner determine shade areas and wind direction. In addition, knowing the incline of the land is important for proper drainage and installation of driveways.

The location and size of city streets are determined by traffic flow during peak hours. Planners consult highway capacity tables to determine the width of streets, percentage distribution of cars leaving the city versus entering, use of public transportation, residential and business traffic, available parking, and traffic light schedules. Pedestrian traffic on sidewalks and the percentage of the street used by pedestrians and bicycles are also estimated to avoid congestion.

    When deciding where buildings should be located, the planner calculates the maximum distance of facilities in a radius around the residents.

Churches and schools are typically within walking distance from residents.

Major shopping outlets and hospitals are located on the outskirts of town.

Industrial facilities are usually on the periphery of a community due to their freight access, noise level, and environmental safety aspect.

City planners also need to know the real estate appraisal of the land they are developing. If the property is already owned, the planners need to offer the owners a fair price. If planners are developing vacant land, they will want to know the value of the new structure they are building. Retail districts, residential, and industrial land each have varying values. Appraisals are based on market value, cost approach, or anticipated income value of

the land.

Another concern in city planning is the character and reputation of the city. Abundant trees and sunlight, social events, shops, and cultural institutions make a city attractive to tourists and visitors. A city with few social services, inadequate sanitation, no community events, many homeless people, and tall skyscrapers that block out light may not be as attractive.

The future of city planning will depend on new technologies to more accurately predict population changes, economic development, and improvements in transportation and public administration.

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Reference

Cosgrove, Holli R., ed. Encyclopedia of Careers & Vocational Guidance, Vol. 4, 11th ed.Chicago: Ferguson Publishing Co., 2000.

DeChiara, Joseph, and Lee Koppelman. Planning Design Criteria. New York: Litton Educational Publishing. 1969.

Whyte, William H.  City: Rediscovering the Center. New York: Bantam Doubleday, 1988.

مواضيع ذات صلة

Remez Algorithm

Quadratic Phase Array

Fractional Fourier Transform

Circulant Matrix

Logistic Map--r=-2

Logistic Map--r=2

Logistic Map--r=4

Lotka-Volterra Equations

Population Growth

Survivorship Curve

Tent Map

Traveling Salesman Problem