Trends in Urban Growth and Objectives of Sound Planning

Architecture & Town Planning (CE - 4702)

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TRENDS IN URBAN GROWTH Introduction:

In order to understand the topic, “trends in urban growth” at first it is imperative to ask; what is meant by urban growth? “Urban growth is the rate of growth of growth of an urban population.” population.”[1] The phrase urban growth also described with its synonym ‘urban sprawl’ which means; “The unplanned, uncontrolled spreading of urban development into areas adjoining the edge of a city.” city.”[2] Similarly another concept is of ‘urbanization’ that needs to be understood while understanding understanding trends in urban growth. “Urbanization (also spelled urbanisation) is the physical growth of rural or natural land into urban areas as a result of population in-migration to an existing urban area. While the exact definition and population size of urbanized areas varies among different countries, urbanization is attributed to growth of cities. Urbanization is also defined by the United Nations as movement of people from rural to urban areas with population growth equating to urban migration. The UN projects projects half the world population will live in urban areas at the end of 2008.” 2008.”[3] In the following the t rends in urban growth shall be discussed in details. Global Urban Population in Developed and Developing Countries: Countries:[4]

The human population has lived a rural lifestyle through most of history. The world’s population, however, however, is quickly becoming urbanized as people migrate to the cities. In 1950, less than 30% of the world’s population lived in cities. This number grew to 47% in the year 2000 (2.8 billion people), and it is expected to grow to 60% by the year 2025. Developed nations have a higher percentage of urban residents than less developed countries. However, urbanization urbanization is occurring rapidly in many less developed countries, and it is expected that most urban growth will occur in less developed countries during the next decades. The definition of an urban area changes from country to country. In general, there are no standards, and

each country develops its own set of criteria for distinguishing cities or urban areas. A city is generally defined as a political unit, i.e., a place organized and governed by an administrative body. A way of defining a city or an urban area is by the number of residents. The United Nations defines settlements of over 20,000 as urban, and those with more than 100,000 as cities. The United States defines an urbanized area as a city and surrounding area, with a minimum population of 50,000. A metropolitan area includes both urban areas and rural areas that are socially and economically integrated with a particular city. Cities with over 5 million inhabitants are known as megacities. There were 41 in the year 2000. This number is expected to grow as the population increase i ncreasess in the next few decades. It is predicted that by the year 2015, 50 megacities megacities will exist, and 23 of these are expected to t o have over 10 million people. Table below is a list of the world’s 2 2 largest cities in 2012. The World's 22 Largest Cities, 2012; Population (Millions)

Source:

©Department of Civil Engineering, University of Lahore (UOL), Lahore, Pak

Course Coordinator: Asst. Prof. Rehan Masood


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United Nations, Population Division. World Urbanization Prospects. 1994 Why is the urban population increasing so fast?

The rapid growth of urban areas is the result of two factors: natural increase in population (excess of births over deaths), and migration to urban areas. The natural population growth rate has always been less than the population growth rate due to migration therefore we must concentrate understanding the phenomenon of migration in detail. Migration is defined as the long-term relocation of an individual, household or group to a new location

outside the community of origin. Today the movement of people from rural to urban areas (internal migration) is most significant. Although smaller than the movement of people within borders, international migration is also increasing. Both internal and international migration contributes to urbanization. Migration is often explained in terms of either “push factors” – conditions in the place of origin which are perceived by migrants as detrimental to their well- being or economic security, and “pull factors” – the circumstances in new places that attract individuals to move there. Examples of push factors include high unemployment and political persecution; examples of pull factors include job opportunities or moving to a better climate. Typically, a pull factor initiates migration that can be sustained by push and other factors that facilitate or make possible the change. For example, a farmer in rural Sindh whose land has become unproductive because of drought (push factor) may decide to move to Karachi City where he perceives more job opportunities and possibilities for a better lifestyle (pull factor). In general, cities are perceived as places where one could have a better life, because of better opportunities, hi gher salaries, better services, and better lifestyles. The perceived better conditions attract poor people from rural areas. In order to better illustrate the causes of rural migration, we will consider policies that have led to migration in many developing countries. In order to pay foreign debt and to be more competitive in international markets, national governments have encouraged the export of national resources and agricultural products. Agricultural products (sugar, flowers, coffee, etc.), and primary-sector goods (timber, fish, minerals, etc) become natural resource capital that can be traded to bolster the national economy. In order to produce agricultural products quickly, efficiently, and for a decent price, national governments often look to decrease the number of small producers, and turn agricultural production and resource extraction over to larger enterprises, with larger production facilities, and a lower per-unit cost of production. This trend turns land into a commodity, that can be bought and sold, and it is viewed only in terms of its productive capabilities. Free market economics pursues economic efficiency to deliver goods at the lowest possible price, and its advocates maintain that any government intervention diminishes this efficiency. Consequently, they seek to eliminate farm programs such as farm subsidies, cheap credit policies, etc. intended to help the farmer, and to maintain stable prices. This scenario leaves farmers to shoulder the burden of farming, sometimes with no alternative but to sell their land to a foreign investor or a domestic-owned enterprise, and move to the cities, where the farmer hopes to have a better life. Other policies reinforce the above scenario. In this case, in order to boost the production of cheaper goods, governments have maintained artificially low food prices in urban areas. The strategy here is to maintain urban food prices below market levels to reduce the cost of urban labor and urban life. This policy has resulted in inadequate compensation of rural producers for the costs they incur to produce food products and t hus have aggravated rural poverty. On the other hand, these policies have also made city life more attractive and pulled them from rural areas. As a result of these policies, an average of 270,000 rural migrants have been arriving in Mexico City annually over the last ten years, transforming it into one of the largest cities in the world.




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International migration includes labor migration, refugees and undocumented migrants. Similar to rural-to-

urban migration, individuals move in search of jobs and a better life. Income disparities among regions, and job opportunities, are key motivating factors. The migration policies of sending and receiving countries also play a key role. The best current estimate from the United Nations Population Fund indicates that more than 100 million people were living outside their countries of birth or citizenship in 1998. There are a number of reasons why this figure is rising, but an important one is that the native labor pool in the industrialized countries is shrinking, while the developing world’s workforce is rapidly increasing. Today, international migration is at an all-time high. About 2% of the Earth’s population has moved away from the country of origin. International refugees contribute to the urban migrant population. The United Nations High Commission for

Refugees (UNHCR) reports that most of the 22 million people who came under its wing in 1997 were fleeing from domestic or international conflict. The Geneva Convention (1951) on Refugees defines refugees as t hose individuals who migrate because of: “….well founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular group, or political opinion……”

Nations honoring the Geneva Convention have an obligation to determine whether, in fact, individuals will truly face persecution at home. Excluded are those who fear famine or are pushed out by natural disasters. The overwhelming majority of refugees come from developing nations, and most of them flee to poor countries. What are the Problems Associated with Rapid Urban Growth?

The urbanization process refers to much more than simple population growth; it involves changes in the economic, social and political structures of a region. Rapid urban growth is responsible for many environmental and social changes in the urban environment and its effects are strongly related to global change issues. The rapid growth of cities strains their capacity to provide services such as energy, education, healthcare, transportation, sanitation and physical security. Because governments have less revenue to spend on the basic upkeep of cities and the provision of services, cities have become areas of massive sprawl, serious environmental problems, and widespread poverty. During the 19th and early 20th centuries, urbanization resulted from and contributed to industrialization.

New job opportunities in the cities motivated the mass movement of surplus population away from the countryside. At the same time, migrants provided cheap, plentiful labor for the emerging factories. Today, due to movements such as globalization, the circumstances are similar in developing countries. Here the concentration of investments in cities attracts large numbers of migrants looking for employment, thereby creating a large surplus labor force, which keeps wages low. This situation is attractive to foreign investment companies from developed countries that can produce goods for far less than if the goods were produced where wages are higher. Thus, one might wonder if urban poverty serves a distinct function for the benefit of global capital. One of the major effects of rapid urban growth is “urban sprawl"-scattered development that increases traffic, saps local resources and destroys open space. Urban sprawl is responsible for changes in the physical environment, and in the form and spatial organization of cities. Developed and less developed countries of the world differ not only in the percent living in cities, but also in the way in which urbanization is occurring. In Mexico City (950 square miles), as in many other megacities in the developing world, urban sprawl exists as nearly 40% of city dwellers live in the urban periphery in poverty and environmental degradation. These high density settlements are often highly polluted owing to the lack of urban services, including running water, trash pickup, electricity or paved roads. Nevertheless, cities provide poor people with more




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opportunities and greater access to resources to transform their situation than rural areas. In the United States, and Pakistan poorly planned urban development is threatening environment, health, and people’s quality of life. Consequences of Urban Growth:

Increases traffic and Squatter Settlements Pollutes air, water and other threats to natural environment Worsens the existing degraded built environment Destroys agricultural land, parks, and open spaces Costs cities and counties millions of dollars for new housing, water and sewer lines, new schools, and increased police and fire protection Creates crowded schools in the suburbs and empty, crumbling schools in center of cities Solutions to decrease Urban Growth:

Enacting growth boundaries, parks and open space protection Planning and promoting public participation in housing and t ransportation. Reversing government programs and tax policies that help create sprawl. Revitalizing already developed areas through measures such as attracting new businesses, reducing crime and improving schools; Preventing new development in floodplains, coastal areas and other disaster- prone areas. Readings and References:

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“International Migration: A Global Challenge”, Population Bulletin, Population Reference Bureau, Inc.., Vol. 51, No. 1, 1996.

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Robert Geodes, Ed., Cities in our Future, Island Press, 1997.

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Samuel P. Hunting ton, The Clash of Civilizations and the Remaking of World Order, Simian and Schuster, 1996.

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Peter van deer Veer, Nation and Migration, University of Pennsylvania Press, 1995

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Joel E. Coven, How Many People can the Earth Support?, Norton, 1995.

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United Nations, International Migration Policies, UN Publication, 1995.

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World Resources 1996 – 1997 : The Urban Environment

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www.aag.org, “Global Change and Urbanization in Latin America”

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www.prb.org, “Human Population: Fundamentals of Growth Patterns of World Urbanization”.

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http://wiki.answers.com/Q/What_is_a_definition_for_Urban_Growth

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http://www.answers.com/topic/urban-sprawl

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http://en.wikipedia.org/wiki/Urbanisation

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http://www.globalchange.umich.edu/globalchange2/current/lectures/urban_gc/index.html [1]http://wiki.answers.com/Q/What_is_a_definition_for_Urban_Growth [2] http://www.answers.com/topic/urban-sprawl [3] http://en.wikipedia.org/wiki/Urbanisation [4]http://www.globalchange.umich.edu/globalchange2/current/lectures/urban_gc/index.html




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OBJECTIVES OF SOUND PLANNING Introduction:

In order to understand the, “Objectives of Sound Planning” at first it is imperative to comprehend a little bit history of urban planning and the planning attempts made by the initiators of planning in the urban contexts. Then one may also ask the questions like; what kind of objectives they had in mind while developing their cities? Whether they have achieved those objectives or not? Do their defined objectives may be referred as objectives of sound planning or not? What is meant by Sound Planning? And how the Objectives for Sound Planning are formulated? In addition it is also important to i dentify the urban context for which the planning is to be done so as one may clearly spell out the objectives of sound planning. Thus in this way one may understand the topic objectives of sound planning. In the following all these questions are addressed in some detail. Urban Planning History:[1] Urban, city, and town planning is the integration of the disciplines of land use planning and transport

planning, to explore a very wide range of aspects of the built and social environments of urbanized municipalities and communities. Urban planning as an organized profession has existed for less than a century. However, most settlements and cities reflect various degrees of forethought and conscious design in their layout and functioning. The development of technology, particularly the discovery of agriculture, facilitated larger populations than

the very small communities, and may have compelled the development of stronger, more coercive governments at the same time. The pre-Classical and Classical ages saw a number of cities laid out according to fixed plans, though many tended to develop organically. Designed cities were characteristic of the totalitarian government. The cities of Harappa and Mohenjo-daro in the Indus Valley Civilization (in modernday Pakistan and northwest India) are perhaps the earliest examples of deliberately planned and managed cities. These ancient cities were unique in that they often had drainage systems, seemingly tied to a welldeveloped ideal of urban sanitation. The Greek Hippodamus (c. 407 BC) is widely considered the father of city planning in the West, for his design of Miletus; Alexander commissioned him to lay out his new city of Alexandria, the grandest example of idealized urban planning of the Mediterranean world, where regularity was aided in large part by its level site near a mouth of the Nile. The ancient Romans used a consolidated scheme for city planning, developed for military defense and civil convenience. Many European towns still preserve the essence of these schemes. The collapse of Roman civilization saw the end of their urban planning, among many other arts. Urban development in the Middle Ages, characteristically focused on a fortress, a fortified abbey, or a (sometimes abandoned) Roman nucleus, occurred "like the annular rings of a tree" whether in an extended village or the center of a larger city. Since the new center was often on high, defensible ground, the city plan took on an organic character, following the irregularities of elevation contours like the shapes that result from agricultural terracing. A few medieval cities were admired for their wide thoroughfares and other orderly arrangements, but the juridical chaos of medieval cities (where the administration of streets was sometimes hereditary with various noble families), and the characteristic tenacity of medieval Europeans in legal matters, prevented frequent or large-scale urban planning until the Renaissance and the enormous strengthening of all central governments, from city-states to the kings of France, characteristic of that epoch. Florence was an early model of the new




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urban planning, which rearranged itself into a star-shaped layout adapted from the new star fort, designed to resist cannon fire. This model was widely imitated, reflecting the enormous cultural power of Florence in this age; the Renaissance was hypnotized by one city type which for a century and a half was impressed upon utopian schemes: this is the star-shaped city Radial streets extend outward from a defined center of military, communal or spiritual power. And, all this occurred in the cities, but ordinarily not in the industrial suburbs characteristic of this era which remained disorderly and characterized by crowded conditions and organic growth. In developed countries (Western Europe, North America, Japan and Australasia), planning and architecture can be said to have gone through various stages of general consensus in the last 200 years. Firstly, there was the industrialised city of the 19th century, where control of building was largely held by businesses and the wealthy elite. Around 1900, there began to be a movement for providing citizens, especially factory workers, with healthier environments. The concept of garden cities arose and several model towns were built, such as Letchworth and Welwyn Garden City in UK. However, these were principally small scale in size, typically dealing with only a few thousand residents. It wasn't until the 1920s that modernism began to surface. Based on the ideas of Le Corbusier and utilising new skyscraper building techniques, the modernist city stood for the elimination of disorder, congestion and the small scale, replacing them instead with preplanned and widely spaced freeways and tower blocks set within gardens. There were plans for large scale rebuilding of cities, such as the Plan Voisin (based on Le Corbusier's Ville Contemporaine), which proposed clearing and rebuilding most of central Paris. No large-scale plans were implemented until after World War II however. Throughout the late 1940s and 1950s, housing shortages caused by war destruction led many cities around the world to build substantial amounts of government-subsidized housing blocks. Planners at the time used the opportunity to implement the modernist ideal of towers surrounded by gardens. The most prominent example of an entire modernist city is Brasilia, constructed between 1956 and 1960 in Brazil. By the late 1960s and early 1970s, many planners were coming to realize that the imposition of modernist clean lines and a lack of human scale also tended to sap vitality from the community. This was expressed in high crime and social problems within many of these planned neighbourhoods. Modernism can be said to have ended in the 1970s when the construction of the cheap, uniform tower blocks ended in many countries, such as Britain and France. Since then many have been demolished and in their way more conventional housing has been built. Rather than attempting to eliminate all disorder, planning now concentrates on individualism and diversity in society and the economy. This is the post-modernist era. Minimally-planned cities still exist. Houston is an example of a large city (with a metropolitan population of 5.5 million) in a developed country, without a comprehensive zoning ordinance. Houston does, however, have many of the land use restrictions covered by traditional zoning regulations, such as restrictions on development density and parking requirements, even though specific land uses are not regulated. Moreover, private-sector developers in Houston have used subdivision covenants and deed restrictions effectively to create the same kinds of land use restrictions found in most municipal zoning laws. Houston voters have rejected proposals for a comprehensive zoning ordinance three times since 1948. Even without zoning in its traditional sense, metropolitan Houston displays similar land use patterns at the macro scale to regions comparable in age and population that do have zoning, such as Dallas. This suggests that factors outside the regulatory environment, such as the provision of urban infrastructure and methods of financing development, may play as big of a role in urban development as municipal zoning. Sustainable development and sustainability have become important concepts in today's urban planning field, with the recognition that current consumption and living habits may be leading to problems such as the overuse of natural resources, ecosystem destruction, urban heat islands, pollution, growing social inequality




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and large-scale climate change. Many urban planners have, as a result, begun to advocate for the development of sustainable cities. However, the notion of sustainable development is a fairly recent concept and somewhat controversial. Wheeler, in his 1998 article, suggests a definition for sustainable urban development to be as "development that improves the long-term social and ecological health of cities and towns." He goes on to suggest a framework that might help all to better understand what a 'sustainable' city might look like. These include compact, efficient land use; less automobile use yet with better access; efficient resource use, less pollution and waste; the restoration of natural systems; good housing and living environments; a healthy social ecology; sustainable economics; community participation and involvement; and preservation of local culture and wisdom. The challenge facing today's urban planners lies in the implementation of targeted policies and programs, and the need to modify existing urban and regional institutions to achieve the goals of sustainability. Aspects of planning: Aesthetics:

In developed countries, there has been a backlash against excessive man-made clutter in the visual environment, such as signposts, signs, and hoardings. Other issues that generate strong debate amongst urban designers are tensions between peripheral growths, increased housing density and planned new settlements. There are also unending debates about the benefits of mixing tenures and land uses, versus the benefits of distinguishing geographic zones where different uses predominate. Regardless, all successful urban planning considers urban character, local identity, and respect for heritage, pedestrians, traffic, utilities and natural hazards. Planners are important in managing the growth of cities, applying tools like zoning to manage the uses of land, and growth management to manage the pace of development. When examined historically, many of the cities now thought to be most beautiful are the result of dense, long lasting systems of prohibitions and guidance about building sizes, uses and features. These allowed substantial freedoms, yet enforce styles, safety, and often materials in practical ways. Many conventional planning techniques are being repackaged using the contemporary term smart growth. There are some cities that have been planned from conception, and while the results often don't turn out quite as planned, evidence of the initial plan often remains. Safety:

Historically within the Middle East, Europe and the rest of the Old World, settlements were located on higher ground (for defense) and close to fresh water sources. Cities have often grown onto, coastal and flood plains at risk of floods and storm surges. Urban planners must consider these threats. If the dangers can be localised then the affected regions can be made into parkland or Greenbelt, often with the added benefit of open space provision. Extreme weather, flood, or other emergencies can often be greatly mitigated with secure emergency evacuation routes and emergency operations centers. These are relatively inexpensive and un-intrusive, and many consider them a reasonable precaution for any urban space. Many cities will also have planned, built safety features, such as levees, retaining walls, and shelters. In recent years, practitioners have also been expected to maximize the accessibility of an area to people with different abilities, practicing the notion of "inclusive design," to anticipate criminal behaviour and consequently to "design-out crime" and to consider "traffic calming" or "pedestrianisation" as ways of making urban life more pleasant. City planning tries to control criminality with structures designed from theories such as socio-architecture or environmental determinism. These theories say that an urban environment can influence individuals' obedience to social rules. The theories often say that psychological pressure develops in more densely developed, unadorned areas. This stress causes some crimes and some use of illegal drugs. The antidote is usually more individual space and better, more beautiful design in place of f unctionalism.




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Oscar Newman’s defensible space theory cites the modernist housing projects of the 1960s as an example of environmental determinism, where large blocks of flats are surrounded by shared and disassociated public areas, which are hard for residents to identify with. As those on lower incomes cannot hire others to maintain public space such as security guards or grounds keepers, and because no individual feels personally responsible, there was a general deterioration of public space leading to a sense of alienation and social disorder. Jane Jacobs is another notable environmental determinist and is associated with the "eyes on the street" concept. By improving ‘natural surveillance’ of shared land and facilities of nearby residents by literally increasing the number of people who can see it, and increasing the familiarity of residents, as a collective, residents can more easily detect undesirable or criminal behaviour. The "broken-windows" theory argues that small indicators of neglect, such as broken windows and unkempt lawns, promote a feeling that an area is in a state of decay. Anticipating decay, people likewise fail to maintain their own properties. The theory

suggests

that

abandonment

causes

crime,

rather

than

crime

causing

abandonment.

Some planning methods might help an elite group to control ordinary citizens. Haussmann's renovation of Paris created a system of wide boulevards which prevented the construction of barricades in the streets and eased the movement of military troops. In Rome, the Fascists in the 1930s created ex novo many new suburbs in order to concentrate criminals and poorer classes away from the elegant town. Other social theories point out that in Britain and most countries since the 18th century, the transformation of societies from rural agriculture to industry caused a difficult adaptation to urban living. These theories emphasize that many planning policies ignore personal tensions, forcing individuals to li ve in a condition of perpetual extraneity to their cities. Many people therefore lack the comfort of feeling "at home" when at home. Often these theorists seek a reconsideration of commonly used "standards" that rationalize the outcomes of a free (relatively unregulated) market. Slums

The rapid urbanization of the last century has resulted in a significant amount of slum habitation in the major cities of the world, particularly in developing countries. There is significant demand for planning resources and strategies to address the issues that arise from slum development. Many planning theorists and practitioners are calling for increased attention and resources in this area, particularly the Commonwealth Association of Planners. When urban planners give their attention to slums, one also has to pay attention to the racial make-up of that area to ensure that racial steering does not occur. The issue of slum habitation has often been resolved via a simple policy of clearance. However, more creative solutions are beginning to emerge such as Nairobi's "Camp of Fire" program, where established slum-dwellers have promised to build proper houses, schools, and community centers without any government money, in return for land they have been illegally squatting on for 30 years. The "Camp of Fire" program is one of many similar projects initiated by Slum Dwellers International, which has programs in Africa, Asia, and South America. Urban decay

Urban decay is a process by which a city, or a part of a city, falls into a state of disrepair and neglect. It is characterized by depopulation, economic restructuring, property abandonment, high unemployment, fragmented families, political disenfranchisement, crime, and desolate urban landscapes. During the 1970s and 1980s, urban decay was often associated with central areas of cities in North America and parts of Europe. During this time period, major changes in global economies, demographics, transportation, and government policies created conditions that fostered urban decay. Many planners s poke of "white flight" during this time. This pattern was different than the pattern of "outlying slums" and "suburban ghettos" found in many cities outside of North America and Western Europe, where central urban areas actually had higher real estate vales. Starting in the 1990s, many of the central urban areas in North America have been experiencing a reversal of




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the urban decay of previous decades, with rising real estate values, smarter development, demolition of obsolete social housing areas and a wider variety of housing choices. Reconstruction & Renewal:

Areas devastated by war or invasion represent a unique challenge t o urban planners. Buildings, roads, services and basic infrastructure like power, water and sewerage are often severely compromised and need to be evaluated to determine what can be salvaged for re-incorporation. There is also the problem of the existing population, and what needs they may have. Historic, religious or social centers also need to be preserved and re-integrated into the new city plan. A prime example of this is the capital city of Kabul, Afghanistan, which, after decades of civil war and occupation, has regions that have literally been reduced to rubble and desolation. Despite this, the indigenous population continues to l ive in the area, constructing makeshift homes and shops out of whatever can be salvaged. Any reconstruction plan proposed needs to be sensitive to the needs of the community and its existing culture, businesses and needs. Urban Reconstruction Development plans must also work with government agencies as well as private interests to develop workable designs. Transport:

Transport within urbanized areas presents unique problems. The density of an urban environment can create significant levels of road traffic, which can impact businesses and increase pollution. Parking space is another concern, requiring the construction of large parking garages in high density areas which could be better used for other development. Good planning uses transit oriented development, which attempts to place higher densities of jobs or residents near high-volume transportation. For example, some cities permit commerce and multi-story apartment buildings only within one block of train stations and multilane boulevards, and accept single-family dwellings and parks farther away. Floor area ratio is often used to measure density. This is the floor area of buildings divided by the land area. Ratios below 1.5 could be considered low density, and plot ratios above five very high density. Most exurbs are below two, while most city centers are well above five. Walk-up apartments with basement garages can easily achieve a density of three. Skyscrapers easily achieve densities of thirty or more. City authorities may try to encourage lower densities to reduce infrastructure costs, though some observers note that low densities may not accommodate enough population to provide adequate demand or funding for that infrastructure. In the UK, recent years have seen a concerted effort to increase the density of residential development in order to better achieve sustainable development. Increasing development density has the advantage of making mass transport systems, district heating and other community facilities (schools, health centers, etc) more viable. However; critics of this approach dub the densification of development as 'town cramming' and claim that it lowers quality of life and restricts market-led choice. Problems can often occur at residential densities between about two and five. These densities can cause traffic jams for automobiles, yet are too low to be commercially served by trains or light rail systems. The conventional solution is to use buses, but these and light rail systems may fail where automobiles and excess road network capacity are both available, achieving less than 1% ridership. The Lewis-Mogridge Position claims that increasing road space is not an effective way of relieving traffic jams as latent or induced demand invariably emerges to restore a socially-tolerable level of congestion.




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Suburbanization:

In some countries, declining satisfaction with the urban environment is held to blame for continuing migration to smaller towns and rural areas (so-called urban exodus). Successful urban planning supported Regional planning can bring benefits to a much larger hinterland or city region and help to reduce both congestion along transport routes and the wastage of energy implied by excessive commuting. Environmental factors:

Environmental protection and conservation are of utmost importance to many planning systems across the world. Not only are the specific effects of development to be mitigated, but attempts are made to minimize the overall effect of development on the local and global environment. This is commonly done through the assessment of Sustainable urban infrastructure. In Europe this process is known as Sustainability Appraisal. In most advanced urban or village planning models, local context is critical. In many, gardening and other outdoor activities assumes a central role in the daily life of citizens. Environmental planners are focusing on smaller systems of resource extraction, energy production and waste disposal. There is even a practice known as Arcology, which seeks to unify the fields of ecology and architecture, using principles of landscape architecture to achieve a harmonious environment for all living things. On a small scale, the eco-village theory has become popular, as it emphasizes a traditional 100-140 person scale for communities. An urban planner is likely to use a number of quantitative tools to forecast impacts of development on the environmental, including roadway air dispersion models to predict air quality impacts of urban highways and roadway noise models to predict noise pollution effects of urban highways. As early as the 1960s, noise pollution was addressed in the design of urban highways as well as noise barriers. The Phase I Environmental Site Assessment can be an important tool to the urban planner by identifying early in the planning process any geographic areas or parcels which have toxic constraints. Light and Sound

The urban canyon effect is a colloquial, non-scientific term referring to street space bordered by very high buildings. This type of environment may shade the sidewalk level from direct sunlight during most daylight hours. While an oft-decried phenomenon, it is rare except in very dense, hyper-tall urban environments, such as those found in Lower and Midtown Manhattan, Chicago's Loop and Kowloon in Hong Kong. In urban planning, sound is usually measured as a source of pollution. Another perspective on urban sounds is developed in Soundscape studies emphasizing that sound aesthetics involves more than noise abatement and decibel measurements. Hedfors coined 'Sonotope' as a useful concept in urban planning to relate typical sounds to a specific place. Due to urban planning, there has been an increase in light and sound pollution that destroys the environment. Urban Planning Process:

The traditional planning process focused on top-down processes where the urban planner created the plans. The planner is usually skilled in either surveying/engineering or architecture, bringing to the town planning process ideals based around these disciplines. They typically worked for national or local governments. Changes to the planning process over past decades have witnessed the metamorphosis of the role of the urban planner in the planning process. More citizens calling for democratic planning & development processes have played a huge role in allowing the public to make important decisions as part of the planning process. Community organizers and social workers are now very involved in planning from the grassroots level. Developers too have played huge roles in influencing the way development occurs, particularly through project-based planning. Many recent developments were results of large and small-scale developers who purchased land, designed the district and constructed the development from scratch. The Melbourne




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Docklands, for example, was largely an initiative pushed by private developers who sought to redevelop the waterfront into a high-end residential and commercial district. Recent theories of urban planning, espoused, for example by Salingaros see the city as a adaptive system that grows according to process similar to t hose of plants. They say that urban planning should thus take its cues from such natural processes. Conclusion:

Conclusively it is now quite clear that, “it is the process of urban planning that a society adopts leads towards determination about objectives of sound planning.” The objectives of sound planning in current time and space especially in our local context of Karachi shall be based upon the understanding level of our decision makers at federal, provincial and local level regarding significance of urban planning and welfare of citizens at large. Thus the objective of sound planning is quite clear i.e. to provide the city of Karachi a healthy and socially safe livable environment. [1] For details please log on to the website:http://en.wikipedia.org/wiki/Urban_planning




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TRENDS IN URBAN GROWTH AND OBJECTIVES OF SOUND PLANNING 1. Introduction:

The current discussion is based on the concept of urban growth trends and objectives behind sound planning. According to, “Harold MacLean Lewis”[1] the trends in urban growth can be visualized through population estimates. He classified the towns with relation to their population sizes. According to his classification the town population begins from 2500 to 5000 persons. He further classified town in ni ne categories. i) 2500 to 5000 persons may be termed as Eopolis or Infantile Municipality Town ii) 5000 to 10000 persons may be termed as Polis or Juvenile Town iii) 10000 to 25000 persons may be termed as Mature Trade/Industrial Town iv) 25000 to 50000 persons may be termed as Metropolis or Medium Size City v) 50000 to 100000 persons may be termed as Megalopolis Intermediate City vi) 100000 to 250000 persons may be termed as Trade/Industry/Service Sector City vii) 250000 to 500000 persons may be termed as Primate City viii) 500000 to 1000000 persons may be termed as Tyranopolis or a Metropolitan City ix) 1000000 or more persons may be termed as Senile City or Mega City

The trends in urban growth can be seen from two major perspectives. One is the trends of emerging urban centers or cities over the period of time and other is the trends of urban growth within urban centers. Considering the first perspective in mind there are t hree different trends of urban growth evident in the world i.e. Development of Mega Cities, Development of Metropolitan Cities and Development of Small and Intermediate Cities or Secondary Cities. i) Development of Metropolitan Cities:

These are cities with population between one million and above up to less than 10 millions. After the First World War up to Second World War the development trends was of metropolitan cities as a hub of economic activities and centers of administration and power. This development trend continued up to Second World War. In this era small manufacturing towns also developed as industrial cities. After the devastating effects of 2nd world war the redevelopment of cites toll place & large cities emerged as primate cities with large economic base. Due to both push and pull factors the urban areas transformed their morphology to greater extent. ii) Development of Mega Cities:

These are the cities with population of Ten million & above. There are total 25 mega cities in the world. The background of mega city development is that, “The population explosions and mass migration towards primate cities caused the phenomenal growth & development in metropolitan cities and they become the economic base for the countries at national level and played their respective role in the co untry’s economic development. The change in these metropolitan cities not only remains at population level but in addition their physical nature

and

morphology

has

increase

to

greater

extent.

These

are

termed

as

mega

cities.

Mega cities are those which have mega economics and mega problems and issues. Such as its administration setup and physical maintenance and management issues. The devastating effects of Second World War also




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give birth to importance of small, secondary and intermediate level cities whose economic base also effect and serve the neighboring rural areas. iii) Development of Small and Intermediate Cities:

These are the cities with population range from 2500 t o less than one million. The development trend of these cities occurred in two different times in the history. At first this trends of cities was evident immediately after Industrial Revolution up to 1st world war and then after Second World War up till now. The current trend is development of small and intermediate cites which has to play an important role in national economics due to security reasons and maintenance and management. The basic reason behind development of such cities is to reduce the pressure of population from primate cities. Secondly such cities are having small size can be better managed and plays a pivotal role in national economics by supporting rural hinter land. 2. What is Urban Growth?

It is basically the growth and development of urban areas, over a period of time. It can also be understood by the term urban sprawl. 3. What is Urban Sprawl?

Urban sprawl is the term to describe development pattern in cities. Unfortunately it lacks a precise definition. However it can be understood through visualizing the on going process of growth in cities. The urban sprawl can refer to at least three different patterns. i) Low density continuous development. ii) Ribbon development. iii) Leapfrog development i) Low – Density Continuous Development Pattern:

This is the development pattern on housing and related land uses in all direction of city. It is also termed as the horizontal growth, which occupy large amount of land and expand the boundary of the city. This development pattern is manly measure for at least 50 years. The

affects

of

low

density

continuous

development

pattern

are

as

follows:

Waste of land resources. It increase the cost of development i.e. utilities, transport. It increases the travel time and energy consumption. ii) Leapfrog Development Pattern:

It is a process of skipping over of parcels of land. This pattern occurs due to various reasons such as property value increase, deteriorating law and order, opportunities of better life & upward mobility. The affects of leapfrog development are as follows: It is unplanned growth that occurs spontaneously. It creates incompatible land uses. iii) Ribbon Development Pattern:

It is the development that follows street, car lines roads. Subways, and commuter railroads, by leaving the interstices undeveloped. Mainly the highways promote ribbon development. Interstices mean space between things / objects. According to Encyclopedia of Urban Planning by Whittick Arnold, “It is an urban development along main roads leading to cites”. According to Mr. G.K. Hiraskar, in t his growth pattern, the

development takes place in the form of Ribbon or line. It is a single row of house, shops, market, commercial




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buildings along the bust routes railway lines, and highways. The ribbon development mostly occurs in newly developing towns where zoning rules and regulations have not been strictly enforced. The affects of Ribbon growth are as follows:

It has only one advantage that resident have access to transport. Its disadvantages are traffic noise, danger for children, stretch of services, and aesthetically it looks bad that’s why the UK has Restriction of Ribbon Development Act 1935. Initially this kind of growth is very small scale along the road side afterwards it occupy whole area and roads become congested and problem of accidents increase. Same is the case of railway lines. This kind of growth cause congestion and over crowding of all types of buildings i.e. Residence, Schools, Factories, Were housing, Petrol Pumps, Shops, Clinics etc. Every body wants to get frontage advantage of main road and the internal land will be left undeveloped which cause wastage of valuable land. Over growing at the road and narrow starts will raise the accidents. All types of buildings will coexist at the road frontage with no regard to zoning regulations, which will affect the health conditions of resident. The town spread will be far and wise which is costly to maintain. The future improvement will become costly. Incompatible land uses will occurs. Ribbon developed is inverse of planned growth because it is an organic growth which is uncontrollable. Therefore it is necessary to check this kind of development before it become problem for the planners. 4. Cellular Growth:

As evident from the term itself the cellular growth is the growth and expansion of cells. What is cell? Cell is basically a unit of planning. Just like different biological organisms grow and expand, or

a cell reproduce itself. Like wise in planning when a planned settlement is developed in a city; the city expands with it. For example KDA announces housing schemes in Karachi. Each settlement which is developed in a scheme can be termed as cell. Therefore, in planning cellular growth means repetition of existing cells in city structure or it is a planned addition of new neighborhoods to existing towns. Cellular growth may also means little more than haphazard urban growth. 5. Linear City:

The linear city concept can also be termed as more refined version of ribbon development. The concept of linear city was developed by Mr. Don Arturo Soria Y. Mata in 1882, in Madrid. According to his concept, “A city should be designed on the principal that transport rout will be the main determinant to develop physical shape / form / morphology of the city.” In linear city the development is arranged in a long narrow

belt along the both sides of road. There may be a series of linear towns along the route to link existing towns. In Pakistan one can find many examples of this nature such as along Indus Highway many towns and villages developed in this pattern. 6. Suburbs and Suburban Growth:

Suburbs are the compactly developed / developing areas in the surrounding of a city. There is no identifiable boundary between city and suburban. However they are distinguished by their homogenous socio-economic and physical characteristics. Cities merge gradually into the suburban areas without and break in the physical aspect. 6.1 Character of Suburbs:

Suburbs can be of different form and function depends on their age, location and circumstances and context within which they are developed. In case of America and Europe (West) they are of three kind’s i.e. old suburbs, new suburbs and former independent communities.




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a) Old Suburbs:

These are developed before the wise use of automobile and prosperity. These suburbs were generally located adjacent to central city. Their residents were of varied income groups. The social classes in old suburbs have commercial area or local shopping and ethnic background. They have very little amount of vacant land. The example of old suburb is PECHS area in Karachi. b) New Suburbs:

These were developed after Second World War. When automobile use increased & people become affluent. They have low density. They have high rate of automobile ownership, high income, abundance of land and enough parking and open space facilities. Gulshan-e-Maymar in Karachi is its example. c) Former Independent Communities:

These suburban communities developed as independent towns due to industry. They have a mixture of commercial, industrial and residential activities. They have mix housing type and varied age income and social class. Steel town, in Karachi is its case example. 6.2 Why Suburban Growth Takes Place:

There are varieties of reasons for suburban growth such as: Rate of land is low, open space are in abundance, city’s congestion increase, fast transport routes developed, & access to automobiles increased. 7. Models & Theories of Urban Growth & City’s Life Cycle:

It is a grave reality that city is a growing entity. Over a period of time city grows and develops. As city grows the habitation starts to takes place in fringe areas. As a repercussion changes and transformations occurs both in city center and suburbs. Considering the growth patterns in different cities all over the world the theories and planners tried to analyze them and established their theories & models for urban growth. Some of these theories & models are as under. According to Lewis Mumford, the urban growth or town growth takes place in six stages with respect to their social order. Each town may pass through these six stages, i.e. Eopolis, Polis, Metropolis, Megalopolis, Tyranopolis and Necropolis. Eopolis:

The Eopolis indicates the first stage of town as a village community whose economic base is agriculture. Polis:

The Polis indicates and association of population with some mechanization and specialization. Metropolis: The metropolis is a city or town which serves as a capital of a state or region. Megalopolis: The megalopolis indicates the first stage of decline in town or city due to mega problems &

issues, or the reign of town or city shows the signs of decline and deterioration. Tyranopolis: the Tyranopolis is the town or city which shows drastic deteriorating situation for example the

trade depression or military powers may occur with different war lords. Necropolis: the necropolis is the worst stage of town or city. For example the citizens are shifting to rural

areas or hinter land or village due to war, disease or economic break down. In that case the town may recover from it after a large internal of time.




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According to Mr. Griffith Taylor a town or city passes through four stages, i.e. Infantile, Juvenile, Mature and senile. Infantile: this is the first stage of town in which a city is not yet divided in separate zones. Or the city in

which zoning regulations is not being prepared yet. Juvenile: the juvenile stage of town or city indicates that, shops are being separated from the houses or

residential area and there are some factories or an industry has been established at a minimal level. Mature: the mature stage of town shows the divisions of residential zone, commercial zone and industrial

zone in the city. Or the landuse and zoning regulations in town shows the stage of mature city / town. Senile: Finally the senile stage of town indicates the physical decay in most of the portions of the city. Or the

physical, social & economic degradation is evident in the built environment of town or city. Apart from these theories of urban growth and process of decay there are some models of urban growth & its pattern of landuse in the form of different theories. These include concentric zone theory or concentric ring theory, Axial Development theory, Sector theory and multiple nuclei theory. These theories of urban development patterns are quite important in landuse planning. Because in landuse planning process the main focus is on conversion of individual parcels of land from rural to urban uses and the role of public and private sector in that conversion. These theories are an attempt to understand and explain that how an urban area grows and what landuse changes occurs in it. it describes the basic urban structure of a city & dynamics of urban growth in town or city. [Self Reading] Concentric Zone / Ring Theory:

The concentric zone theory is based on the pioneering work of Ernest. W. Burgess who have carried out the empirical studies of Chicago and developed the concentric Rings theory. He i dentified five zones of landuse in the city. The figure developed by him shows the typical process of urban growth by five numbers of concentric circles which emerged & expands form CBD. The fist concentric circle of central business District (CBD) represents the center of activity generally close to the site of original settlement. The concentric circle means that some thing which converges to a f ocal factor. For example if we think of a smaller commun9ty the house of a land lord will be the focal point or in ancient or medieval time the palace of king & temple was a focal point in city. Like wise in this theory CBD is that focal point of an urban area. It also represents the old town areas or origin of city which has a central position in expansion. The second concentric circle represents the transition zone which consists of mix commercial and industrial land uses. It means the areas around CBD are subject to changes and transformations in which the old residences transform into business and industrial landuse. Such as wholesaling and warehousing activities. The third zone represents the landuse of low income housing in metropolitan area which contains old housing units or housing of workers of CBD. It is developed due to easy access to job or working area proximity to place of living. The fourth zone represents a middle income housing zone that includes some of the old suburbs. In this zone good residential facilities are evident for high income group where as this zone also comprise exclusive districts for high income people. The fifth and final zone is of newer suburban developments or commuters who use the fastest transport routes. This zone consists of high class residences and the outer limit of this zone has one hour journey to CBD. If one analyze this model of given pattern and growth situation it will be evident that, each zone held to invade the




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outer adjacent zone with a rippling effect. With decline enlarges intro central zone. The basic concept of this theory is that similar activities will locate at the same distance from the center of an urban area. The landuse in each zone depends upon its ability to pay the price for proximity to city center or CBD. In this growth model each zone would have a homogeneous landuse as the physical growth proceed outward from the center and the area occupied would have similar characteristics. From economic point of view the concentric zone is only possible when the site of growth will be located equidistant from center irrespective of direction. According to this theory the process of urban growth is of radial expansion from city center. Although this model is very simple but it has a certain description value. Axial Development Theory:

The axial development theory is a continuation of concentric zone theory because its basic premise is same i.e. accessibility to a single focal point. However in this theory the accessibility is measured in terms of time and physical distance and focus is given to transport facilities in an urban area. This theory explains that as the movement will be concentrated along a particular route therefore development also takes place on this route. Thus urban expansion can be controlled by available transport facilities. It is an extension of each landuse type will develop along major transport route and as a repercussion star shape pattern of landuse will occur in urban built up area. Where as the number of arms of star depends upon the major transport routes in a city. The limit to this development along main transport routes is set through the area development closer to center with less distance to center. Therefore basically this theory explains about the shape of urban built up areas by introducing some transport routes in addition to peripheral expansion by transport radials. And in this kind of development

the

pattern

of

internal

landuse

will

be

of

irregularly

shaped

zones.

Sector Theory:

The sector theory is the refinement of both axial development theory and concentric zone theory. The sector theory was first proposed by Homer Hoyt in 1939. In this theory the focus of attention is a particular landuse growth & development. It suggests the cities grow not in strict concentric zones but rather in sectors similar type of development. This theory explains that the growth t akes place along a particular axis of transport route with mainly similar type of landuse. Each sector consist a homogeneous landuse which expands outward in a particular direction away from the CBD. The residential areas might expand along with existing transportation links, topographical features or natural amenities such as Chicago’s gold cost and north suburbs clearly show this pattern. Thus the major attempt of sector theory is to explain the pattern of urban growth from the view point of residential landuse changes. According to sector theory the growth of n urban area is related with extension of residential districts or more appropriately said the movement of high income residential areas enclosed on each side by middle income group, develops at the edge of existing settlements. The growth for high income housing develops along fastest transport routes up to and edge of an urban area. Beyond which there may be pleasant open country. Some times the direction of this growth may be established by real estate developers. It is quite common practiced that people try to live near the similar social and income class which results in separation in the residential landuse. And as the higher income people can afford better housing & access to amenable environment therefore they can live away from their work place. Whereas; the low income people line on those locations which are low cost & affordable to them near their workplace. The limitation & in adequacy of sector theory is that it can not define rate of growth in different parts of t he city or the causes of urban growth and those factors that affects the location of employment opportunities. Especially in case of low in come housing development around the new employment opportunities in suburban or fringe area as evident in our local context the sector theory is silent.




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Multiple Nuclei Theory:

The Multiple nuclei theory was developed in 1945 by the Chauncey Harris & Edward Ullman after its initial exploration by Mr. R.D. McKenzie. This theory is quite varied from previous theories & models which explained that down town area or CBD is the only focal pint or nuclei of the city. This theory advocates that down town area or CBD can not be considered as an only nuclei or focal point for growth. This theory explains that in urban area there may be more than one focal point or multiple nuclei that can affect the location of certain land uses with increased intensity. In this theory the landuse patterns are visualized as series of nuclei develops in a city in which each nucleus can have different function. Each center develops as nuclei from the spatial interdependence of certain functions. For example manufacturing and transport uses may for on nuclei’s. Like wide hotel, offices and transshipment facilities may develop aro8unjd and air port or sea port areas as evident in Chicago’s’ O’Hare field or KPT area in Karachi. Basically this theory suggests four manor principles of separate nuclei and different districts in it. Principle No 1: Certain activities requires and especial condition of access. For example retailing activity and

accessibility had main coordination. Principle No 2: Certain activities get benefited from grouping. For example a particular, single kind of market

exists together. Principle No 3: Certain activities are detrimental to each other location. For example some activities require supports services. Principle No 4: Certain activities are unable to afford the market price of most desirable sites.

With the expansion of an urban area more specialized nuclei can emerge. In all major urban areas & cities the CBD is located near the inter city transport. The CBD may not be in the center of city but can be developed at an edge of city or built up areas. It depends on the asymmetrical growth of city or urban area. In an urban area Industry, whole sailing & ware housing develops near inter city transport areas. Where as the heavy industry is located away from the main part of the city or urban areas. As the city size increases the residential districts will show an increasing differentiation. In this way the cultural center and entertainment centers or suburban business districts will take a form of other nuclei in the city. Beyond the built up area, settlements which develops as a repercussion of rail services for commuters and private car use. This theory also explains about the irregular pattern of urban landuse because development occurs from different centers, which means the particular pattern of landuse emerge at each different urban area with no common basic pattern of development. Conclusively; all the theories explained above adds to our knowledge of the cities. Because when the sectors developed in cities and the transit & highways elongated the landuse patterns; eventually a nuclei develop or more appropriately said that transportation and economic development added new dimensions to the landuse of the city. Therefore whenever the landuse patterns of a large old city is evaluated; that has gone through such changes; it may be possible to find all these landuse patterns. It is very rare that contemporary cities show entirely one theory of the landuse change. Finally it is also evident from these theories or models of urban Growth that it only focused on the affects of growth on urban development pattern. Whereas the causes of urban growth is not addressed in these theories; because all theories have an assumption that an urban area will grow in size or physical morphology will change & the growth of city is taken for granted. 7. Objectives of Sound Planning:

According to Harold MacLean Lewis; Whatever the plan may be, but it should have reasonable foresight to be adapted to new conditions with little disturbance and destruction in making improvements. The work of planning should be assigned to people who have a vision, technical training and experience. A reasonable plan once decide, should be implemented with




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its essential features without any demand and opposition and that is sound planning. However the objectives of sound planning are to have flexibility in plans to adopt change. Foe instance if informal development is more than formal development, then it should be regulated. The efforts & investments of people shall not be destroyed so as resources shall not go waste & that is the objective of sound planning. The logic behind regulation of informal sector is the failure of formal sector in provision of services and infrastructure for example, will it be possible for a poor person to have concrete house? Or can they get the services of an engineer or hire an architect who can provide low cost solutions? The answer is definitely no. So if a poor person made his house without standards he must be regulated not bulldozed. Another thing that must be kept in mind that, who made the great cities? Princes; Kings; some Powerful People or an Institution of Government. So what is their objective to make a new city? Mainly their objective is to develop capital cities as a place of their importance at national and international level to get praise for them from generations to come. Now what a great city Islamabad is? The planners of Islamabad wanted to have a capital in cool climate because people work efficiently in cool climate. Now due to decision maker’s choice of cool climate billion of rupees of a poor country were spent on it. So can we justify such an objective for sound planning? 8. Conclusions:

Thus conclusively the current discussion leads us to following realities. i. ii.

Urban growth can be spontaneous on its own or planned growth as directed by the authorities. The concept of planning is to provide a vision for future well before the people actually settle in the settlements and planning may also be appropriate enough to facilitate the process of housing the poor in the city.

iii.

The basic planning component is that incompatible land uses should not be allowed or located together.

iv.

Circulation, transport, infrastructure and land use management are the basic tools of planning to guide the urban growth and transformation in the city.

v.

Suburban growth shall be seen as the series of phases through which a particular location passes or it is the development which proceed from an open land to mature urban development

vi.

The objectives of sound planning should be to develop a set of simple guidelines, or principles which should be comprehensive and adaptable to changing conditions of the future.

[1] Harold MacLean Lewis is the author of book “Planning the Modern City”, 1978, New York, USA.



Trends in Urban Growth and Objectives of Sound Planning

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