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SES 874ISSUES IN URBAN DESIGN PLANNING ANDMANAGEMENTPRESENTER: Geofrey YatorQUESTION:Spatial and Local Theories of urbanDevelopment
IntroductionSpatial is relating to spaceUrbanization is the movement of population from rural tourban areasA theory is an organized system of accepted knowledgethat applies in a variety of circumstances to explain aspecific set of phenomena.Urbanization is a relatively new global issueIn 1950 only 30% of the world’s population was urbanizedand 50% in 2009 lived in urban centresThe big question is how do towns come about to be?
Theories explaining the emergence oftownsCentral place theoryExamples. Polders of the Netherlands, the Fens ofEast Anglia in the UKDeveloped by the German geographer WalterChristaller in 1933It explains the reasons behind the distributionpatterns, size, and number of cities and towns.Tested in Southern Germany and came to theconclusion that people gather together in cities toshare goods and ideas and that they
Central place theoryAssumptionshumans will always purchase goods from theclosest placeunbounded isotropic (all flat), homogeneous,limitless surfaceevenly distributed populationall settlements are equidistant and exist in atriangular lattice patternevenly distributed resources
Public choice theoryAdvanced by Paul Peterson in his 1981 book, CityLimitsStates that urban politicians and governingregimes are subordinate to the overall economicprinciples that force cities to compete to capturenew investment and capital.The competitive nature of cities encourages thebusiness elite and politicians to favour newdevelopment
Theories explaining how townsare arrangedGrid model/Hippodamian planExamples; The city of PrieneProposed by Hippodamus of Miletus who isconsidered the father of rational city planningThe center of the city contains the agora (Marketplace), theaters, and temples. Private roomssurround the city’s public arenas.The plan can be laid out uniformly over any kindof terrain since it’s based on angles andmeasurements.
Grid model/Hippodamian planHippodamian plan /Grid Model used in Priene city
Concentric Zone modelAlso known as The Burgess Model, The Bulls EyeModelDeveloped in the 1920s by the urban sociologistErnest Burgess.The model portrays how cities social groups arespatially arranged in a series of rings.The size of the rings may vary, but the orderalways remains the same.
Concentric Zone model1. Central Business District (CBD) - This area ofthe city is a non-residential area and it’s wherebusinesses are. This area s called downtown ,a lotof sky scrapers houses government institutions,businesses, stadiums, and restaurants2. Zone of Transition- the zone of transitioncontains industry and has poorer-quality housingavailable.Created by subdividing larger housesinto apartments
Concentric Zone model3. Zone of the working class- This area containsmodest older houses occupied by stable, workingclass families. A large percentage of the people inthis area rent.4. Zone of better residence- This zone containsnewer and more spacious houses. Mostly familiesin the middle-class live in this zone.5.Commuter’s Zone/Suburbs- This area is locatedbeyond the build-up area of the city. Mostly upperclass residents live in this area.....DesktopModelsBurgess circle model.htm
Concentric Zone modelShortcomingsIt assumes an isotropic plainland may restrict growth of certain sectorsThe model does not fit polycentric citiesIt describes the peculiar Americangeography, where the inner city is poorwhile suburbs are wealthy; the converse isthe norm elsewhere.
Sector model.Chicago and Newcastle upon Tyne/NewcastleDeveloped in 1939 by land economist HomerHoytIt is a model of the internal structure of cities.Social groups are arranged around a series ofsectors, or wedges radiating out from the centralbusiness district (CBD) and centred on majortransportation lineslow-income households to be near railroad lines,and commercial establishments to be alongbusiness thoroughfares
Stresses the importance of transportation corridors. Seesgrowth of various urban activities as expanding along roads,rivers, or train routes.Modeling Cities: Hoyt
Sector model.ShortcomingsApplies well to some towns onlyLow cost housing is near industry andtransportation proving Hoyt’s modelTheory based on 20th century and does not takeinto account cars which make commerce easierWith cars, people can live anywhere and furtherfrom the city
Multiple Nuclei methodThe Multiple Nuclei Model is an ecological modelcreated by Chauncy Harris and Edward Ullman inthe 1945City grows from several independent points ratherthan from one central business district.As these expand, they merge to form a singleurban area.Ports, universities, airports and parks also act asnodesBased on the idea that people have greatermovement due to increased car ownership.
Multiple nuclei modelThe model has four geographic principles– Certain activities require highly specialised facilities• Accessible transportation for a factory• Large areas of open land for a housing tract– Certain activities cluster because they profit frommutual association– Certain activities repel each other and will not be foundin the same area– Certain activities could not make a profit if they paidthe high rent of the most desirable locations
Stresses the importance of multiple nodes of activity, not asingle CBD. Ports, airports, universities attract certain useswhile repelling others.Modeling Cities:Harris-Ullman
Multiple nuclei modelAssumptionsLand is FlatEven Distribution ofResourcesEven Distribution ofpeople in ResidentialareasEven TransportationCostsCriticismsEach zone displays asignificant degree of internalheterogeneityand not homogeneityNo consideration ofinfluence of physical reliefand government policy.Not applicable to orientalcities with different cultural,economic and politicalbackgrounds
Urban Realms ModelFrancisco Bay areaDeveloped by James E. Vance Jr. in the 1960’sEach realm is a separate economic, social andpolitical entity that is linked together to form alarger metro frameworksuburbs are within the sphere of influence of thecentral city and its metropolitan CBDNow urban realms have become, so large they evenhave exurbs, not just suburbs
Urban realm depends onOverall size of themetropolitan regionAmount of economicactivity in each urbanrealmTopography and majorland featuresInternal accessibility ofeach realm
Core frame modelThe Core frame model is a model showingthe urban structure of the Central BusinessDistrict of a town or city.The model includes an inner core whereland is expensive and used intensivelyThe outer core and frame have lower landvalues and are less intensively developed. Tvarious land uses are linked to the bid renttheory
Bid rent theorygeographical economic theory that refers to howthe price and demand for real estate change as thedistance from the central business district (CBD)This is based upon the idea that retailestablishments wish to maximize theirprofitability, so they are much more willing to paymore for land close to the CBD and less for landfurther away from this area.The amount they are willing to pay is called "bidrent".
Irregular pattern modelArrangement of Public space thatcharacterizes the stage of "Transition fromvillage to city" especially in Third World.This urban model is due to lack of planningor construction and illegal without aspecific order.Includes blocks with no fixed order, orpermanent and temporary structures. Sstructures are not related to an urban centresnear the place
Howard gardensLetchworth Garden City, Welwyn Garden cityDeveloped by Sir Ebenezer Howard (1898)Inspired by the idea of ideal/Utopian citiesInspired works on Model villages by Robert Owenand Model industrial towns by Buckingham.Comprised of Town, Country and Town-countryinteractions