Urban planning

"Housing and Urban Development" redirects here. For the Cabinet department of the United States government, see United States Department of Housing and Urban Development.

Urban planning designs settlements, from the smallest towns to the largest cities. Shown here is Hong Kong from Western District overlooking Kowloon, which are separated by the Victoria Harbour.

Urban planning (urban, city, and town planning) incorporates areas such as economics, design, ecology, sociology, geography, law, political science, and statistics to guide and ensure the orderly development of settlements and communities.^[1]

Prominent features of urban planning are land use planning, zoning, environmental planning and transportation planning. Urban planning can include urban renewal, by adapting urban planning methods to existing cities suffering from decay and lack of investment.^[2]

History

Map of Piraeus, the port of Athens, showing the grid plan of the city.

In the Neolithic period, agriculture and other techniques facilitated larger populations than the very small communities of the Paleolithic, which probably led to the stronger, more coercive governments emerging at that time. The pre-Classical and Classical periods saw a number of cities laid out according to fixed plans, though many tended to develop organically. Designed cities were characteristic of the Mesopotamian, Harrapan, and Egyptian civilizations of the third millennium BCE (see Urban planning in ancient Egypt).

Distinct characteristics of urban planning from remains of the cities of Harappa, Lothal, and Mohenjo-daro in the Indus Valley Civilization (in modern-day northwestern India and Pakistan) lead archeologists to conclude that they are the earliest examples of deliberately planned and managed cities.^[3][4] The streets of many of these early cities were paved and laid out at right angles in a grid pattern, with a hierarchy of streets from major boulevards to residential alleys. Archaeological evidence suggests that many Harrapan houses were laid out to protect from noise and enhance residential privacy; many also had their own water wells, probably for both sanitary and ritual purposes. These ancient cities were unique in that they often had drainage systems, seemingly tied to a well-developed ideal of urban sanitation.^[3]

The Greek Hippodamus (c. 407 BC) has been dubbed the "Father of City Planning" 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 ancient Mediterranean world, where the city's regularity was facilitated by its level site near a mouth of the Nile. The Hippodamian, or grid plan, was the basis for subsequent Greek and Roman cities.^[5]

The ancient Romans used a consolidated scheme for city planning, developed for military defense and civil convenience. The basic plan consisted of a central forum with city services, surrounded by a compact, rectilinear grid of streets, and wrapped in a wall for defense. To reduce travel times, two diagonal streets crossed the square grid, passing through the central square. A river usually flowed through the city, providing water, transport, and sewage disposal.^[6] Many European towns, such as Turin, preserve the remains of these schemes, which show the very logical way the Romans designed their cities. They would lay out the streets at right angles, in the form of a square grid. All roads were equal in width and length, except for two, which were slightly wider than the others. One of these ran east–west, the other, north–south, and intersected in the middle to form the center of the grid. All roads were made of carefully fitted flag stones and filled in with smaller, hard-packed rocks and pebbles. Bridges were constructed where needed. Each square marked by four roads was called an insula, the Roman equivalent of a modern city block.

The ideal centrally planned urban space: Sposalizio by Raphael Sanzio, 1504

Each insula was 80 yards (73 m) square, with the land within it divided. As the city developed, each insula would eventually be filled with buildings of various shapes and sizes and crisscrossed with back roads and alleys. Most insulae were given to the first settlers of a Roman city, but each person had to pay to construct his own house.

The city was surrounded by a wall to protect it from invaders and to mark the city limits. Areas outside city limits were left open as farmland. At the end of each main road was a large gateway with watchtowers. A portcullis covered the opening when the city was under siege, and additional watchtowers were constructed along the city walls. An aqueduct was built outside the city walls.

The collapse of Roman civilization saw the end of Roman urban planning, among 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",^[7] 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.

The ideal of wide streets and orderly cities was not lost, however. A few medieval cities were admired for their wide thoroughfares and orderly arrangements, but the juridical chaos of medieval cities (where the administration of streets was sometimes passed down through noble families), and the characteristic tenacity of medieval Europeans in legal matters prevented frequent or large-scale urban planning until the Renaissance and the early-modern strengthening of central government administration, as European (and soon after, North American) society transited from city-states to what we would recognize as a more modern concept of a nation-state.

Florence was an early model of the new urban planning, which took on 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; "[t]he Renaissance was hypnotized by one city type which for a century and a half— from Filarete to Scamozzi— was impressed upon utopian schemes: this is the star-shaped city".^[8] Radial streets extend outward from a defined center of military, communal or spiritual power.

Only in ideal cities did a centrally planned structure stand at the heart, as in Raphael's Sposalizio (Illustration) of 1504. As built, the unique example of a rationally planned quattrocento new city center, that of Vigevano (1493–95), resembles a closed space instead, surrounded by arcading.

Filarete's ideal city, building on Leone Battista Alberti's De re aedificatoria, was named "Sforzinda" in compliment to his patron; its twelve-pointed shape, circumscribable by a "perfect" Pythagorean figure, the circle, took no heed of its undulating terrain in Filarete's manuscript.^[9] This process occurred in cities, but ordinarily not in the industrial suburbs characteristic of this era (see Braudel, The Structures of Everyday Life), which remained disorderly and characterized by crowding and organic growth.

Following the 1695 bombardment of Brussels by the French troops of King Louis XIV, in which a large part of the city center was destroyed, Governor Max Emanuel proposed using the reconstruction to completely change the layout and architectural style of the city. His plan was to transform the medieval city into a city of the new baroque style, modeled on Turin, with a logical street layout, with straight avenues offering long, uninterrupted views flanked by buildings of a uniform size. This plan was opposed by residents and municipal authorities, who wanted a rapid reconstruction, did not have the resources for grandiose proposals, and resented what they considered the imposition of a new, foreign, architectural style. In the actual reconstruction, the general layout of the city was conserved, but it was not identical to that before the cataclysm. Despite the necessity of rapid reconstruction and the lack of financial means, authorities did take several measures to improve traffic flow, sanitation, and the aesthetics of the city. Many streets were made as wide as possible to improve traffic flow.

During the Second French Empire, Haussmann transformed the medieval city of Paris into a modern capital, with long, straight, wide boulevards. The planning was influenced by many factors, not the least of which was the city's history of street revolutions.

Many Central American civilizations also planned their cities, including sewage systems and running water. In Mexico, Tenochtitlan was the capital of the Aztec empire, built on an island in Lake Texcoco in what is now the Federal District in central Mexico. At its height, Tenochtitlan was one of the largest cities in the world, with over 200,000 inhabitants.^[10]

Modern urban planning dates from the 1850s and the contrasting projects to update Paris and extend Barcelona. In 1852, Baron Georges-Eugène Haussmann was commissioned to remodel the Medieval street plan of Paris by demolishing swathes of the old city and laying out wide boulevards, extending outwards beyond the old city limits. Haussmann's encompassed all aspects of urban planning, both in the centre of Paris and in the surrounding districts, with regulations imposed on building facades, public parks, sewers and water works, city facilities, and public monuments. Beyond aesthetic and sanitary considerations, the wide thoroughfares facilitated troop movement and policing.^[11]

The plan chosen to extend Barcelona was a rigorous project based on a scientific analysis of the city and its modern requirements. It was drawn up by the Catalan engineer Ildefons Cerdà to fill the space beyond the city walls after they were demolished after 1854. He is credited with inventing the term ‘urbanization’ and his approach was codified in his General Theory of Urbanization (1867). Cerdà's Eixample (Catalan for 'extension') consisted of 550 regular blocks with chamfered corners to facilitate the movement of trams, crossed by three wider avenues. His objectives were to improve the health of the inhabitants, towards which the blocks were built around central gardens and orientated NW-SE to maximize the sunlight they received, and assist social integration. ^[12]

Ebenezer Howard's influential 1902 diagram, illustrating urban growth through garden city "off-shoots"

In the developed countries of Western Europe, North America, Japan, and Australasia, planning and architecture can be said to have gone through various paradigms or stages of consensus in the last 200 years. Firstly, there was the industrialised city of the 19th century, where building was largely controlled by businesses and wealthy elites. Around 1900, a movement began for providing citizens, especially factory workers, with healthier environments. The concept of the garden city arose and several model towns were built, such as Letchworth and Welwyn Garden City in Hertfordshire, UK, the world's first garden cities. These were small in size, typically providing for a few thousand residents.^[13]

In the 1920s, the ideas of modernism began to surface in urban planning. Based on the ideas of Le Corbusier and using new skyscraper-building techniques, the modernist city stood for the elimination of disorder, congestion, and the small scale, replacing them with preplanned and widely spaced freeways and tower blocks set within gardens. There were plans for large-scale rebuilding of cities in this era, 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 wartime destruction led many cities to subsidize housing blocks. Planners used the opportunity to implement the modernist ideal of towers surrounded by gardens. The most prominent example of an entire modernist city is Brasilia in Brazil, constructed between 1956 and 1960.

Reaction

By the late 1960s and early 1970s, many planners felt that modernism's clean lines and lack of human scale sapped vitality from the community, blaming them for high crime rates and social problems.^[14]

Modernist planning fell into decline in the 1970s when the construction of cheap, uniform tower blocks ended in most countries, such as Britain and France. Since then many have been demolished and replaced by other housing types. 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.^[14]

Minimally planned cities still exist. Houston is a large city (with a metropolitan population of 5.5 million) in a developed country without a comprehensive zoning ordinance. Houston does, however, restrict development densities and mandate parking, even though specific land uses are not regulated. Also, private-sector developers in Houston use subdivision covenants and deed restrictions to effect land-use restrictions resembling zoning laws. Houston voters have rejected comprehensive zoning ordinances three times since 1948. Even without traditional zoning, metropolitan Houston displays large-scale land-use patterns resembling zoned regions comparable in age and population, such as Dallas. This suggests that non-regulatory factors such as urban infrastructure and financing may be as important as zoning laws in shaping urban form.

Sustainable development and sustainability

Sustainable development and sustainability influence today's urban planners. Some planners argue that modern lifestyles use too many natural resources, polluting or destroying ecosystems, increasing social inequality, creating urban heat islands, and causing climate change. Many urban planners, therefore, advocate sustainable cities.^[15]

However, sustainable development is a recent, controversial concept.^[15] Wheeler, in his 1998 article, defines sustainable urban development as "development that improves the long-term social and ecological health of cities and towns." He sketches a 'sustainable' city's features: compact, efficient land use; less automobile use, yet better access; efficient resource use; less pollution and waste; the restoration of natural systems; good housing and living environments; a healthy social ecology; a sustainable economy; community participation and involvement; and preservation of local culture and wisdom.^[15]

Because of political and governance structures in most jurisdictions, sustainable planning measures must be widely supported before they can affect institutions and regions. Actual implementation is often a complex compromise.^[16]

Collaborative Strategic Goal Oriented Programming (CoSGOP) is a collaborative and communicative way of strategic programming, decision-making, implementation, and monitoring oriented towards defined and specific goals. It is based on sound analysis of available information, emphasizes stakeholder participation, works to create awareness among actors, and is oriented towards managing development processes. It was adopted as a theoretical framework for analyzing redevelopment processes in large urban distressed areas in European cities (see “LUDA : Improving quality of life in Large Urban Distressed Areas” project – Research funded by the European Commission, EVK4-CT2002-00081).

Background of CoSGOP'

CoSGOP is derived from goal-oriented planning (Gesellschaft für Technische Zusammenarbeit - GTZ 1988), which was oriented towards the elaboration and implementation of projects based on a logical framework, which was useful for embedding a specific project in a wider development frame and defining its major elements. This approach had weaknesses: its logical rules were strictly applied and the expert language did not encourage participation. CoSGOP introduced a new approach characterized by communication with and active involvement of stakeholders and those to be affected by the program; strategic planning based on the identification of strengths and weakness, opportunities and threats, as well as on scenario-building and visioning; the definition of goals as the basis for action; and long-term, flexible programming of interventions by stakeholders.

Elements of CoSGOP

CoSGOP is not a planning method but a process model. It provides a framework for communication and joint decision-making, in a structured process characterized by feedback loops. It also facilitates stakeholder learning. The essential elements of CoSGOP are analysis of stakeholders (identifying stakeholders’ perceptions of problems, interests, and expectations); analysis of problems and potentials (including objective problems and problems and potentials perceived by stakeholders); development of goals, improvement priorities, and alternatives (requiring intensive communication and active stakeholder participation); specification of an improvement program and its main activities (based on priorities defined with the stakeholders); assessment of possible impacts of the improvement program; definition and detailed specification of key projects and their implementation; continuous monitoring of improvement activities, feedback, and adjustment of the programme (including technical and economic information and perceptions of stakeholders).

The graphical scheme of the Detailed Urbanist Plan for a settlement within the Municipality of Aerodrom within the City of Skopje, Republic of Macedonia.

Application

CoSGOP has been applied in European cross-border policy programming, as well in local and regional development programming. In 2004, the CoSGOP model was applied in the LUDA Project, starting with an analysis of the European experience of urban regeneration projects.

References^[17][18][19]

Collaborative planning in the United States

Collaborative planning arose in the US in response to the inadequacy of traditional public participation techniques to provide real opportunities for the public to make decisions affecting their communities. Collaborative planning is a method designed to empower stakeholders by elevating them to the level of decision-makers through direct engagement and dialogue between stakeholders and public agencies, to solicit ideas, active involvement, and participation in the community planning process. Active public involvement can help planners achieve better outcomes by making them aware of the public’s needs and preferences and by using local knowledge to inform projects. When properly administered, collaboration can result in more meaningful participation and better, more creative outcomes to persistent problems than can traditional participation methods. It enables planners to make decisions that reflect community needs and values, it fosters faith in the wisdom and utility of the resulting project, and the community is given a personal stake in its success.^[20]

Experiences in Portland and Seattle have demonstrated that successful collaborative planning depends on a number of interrelated factors: the process must be truly inclusive, with all stakeholders and affected groups invited to the table; the community must have final decision-making authority; full government commitment (of both financial and intellectual resources) must be manifest; participants should be given clear objectives by planning staff, who facilitate the process by providing guidance, consultancy, expert opinions, and research; and facilitators should be trained in conflict resolution and community organization.^[21][22]

Aspects

Aesthetics

Towns and cities have been planned with aesthetics in mind. Here in Bath, England, 18th-century private sector development was designed to appear attractive.

In developed countries, there has been a backlash against excessive human-made clutter in the visual environment, such as signposts, signs, and hoardings.^[23] Other issues that generate strong debate among urban designers are tensions between peripheral growth, housing density and new settlements. There are also debates about the mixing tenures and land uses, versus distinguishing geographic zones where different uses dominate. Regardless, all successful urban planning considers urban character, local identity, respects heritage, pedestrians, traffic, utilities and natural hazards.

Planners can help manage the growth of cities, applying tools like zoning and growth management to manage the uses of land. Historically, many of the cities now thought the most beautiful are the result of dense, long lasting systems of prohibitions and guidance about building sizes, uses and features.^[24] 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. (See List of planned cities)

Safety and security

The medieval walled city of Carcassonne in France is built upon high ground to provide maximum protection from attackers.

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 green belt, 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 centres. These are relatively inexpensive and unintrusive, 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.

Some city planners try to control criminality with structures designed from theories such as socio-architecture or architectural determinism a subset of environmental determinism. These theories say that an urban environment can influence individuals' obedience to social rules and level of power. Refer to Foucault and the Encyclopedia of the Prison System for more details. 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 functionalism.^{[citation needed]}

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 behavior. However, this is not a new concept. This was prevalent throughout the middle eastern world during the time of Mohamad^{[citation needed]}. It was not only reflected in the general structure of the outside of the home but also the inside. (refer to various religious texts and archaeological sites)

Jacobs went further, though, in emphasizing the details in how to achieve this 'natural surveillance', in stressing the necessity of multiple uses on city streets, so that different people co-mingle with different stores and parks in a condensed part of city space.^[25] By doing this, as well as by making city streets interesting, she theorized a continuous animation of social actions during an average city day, which would keep city streets interesting and well occupied throughout a 24 hour period. She presented the North End in Boston, Massachusetts, as an idealization of this persistent occupation and tasking in a condensed city space, as a model for criminal control.

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.^[26]

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 live 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

Main article: Slums

The rapid urbanization of the last century caused more slums in the major cities of the world, particularly in developing countries. Planning resources and strategies are needed to address the problems of slum development. Many planners are calling for slum improvement, particularly the Commonwealth Association of Planners.^[27] When urban planners work on slums, they must cope with racial and cultural differences to ensure that racial steering does not occur.

Slums were often "fixed" by clearance. However, more creative solutions are beginning to emerge such as Nairobi's "Camp of Fire" program, where established slum-dwellers promise to build proper houses, schools, and community centers without government money, in return for land on which 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.^[28]

Decay

Main article: 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 Europe. During this time, changes in global economies, demographics, transportation, and policies fostered urban decay.^[29] Many planners spoke 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 values.

Starting in the 1990s, many of the central urban areas in North America have been experiencing a reversal of the urban decay, with rising real estate values, smarter development, demolition of obsolete social housing and a wider variety of housing choices.^[5]

Reconstruction and renewal

Main article: Urban renewal

The overall area plan for the reconstruction of Kabul's Old City area, the proposed Kabul - City of Light Development.

Areas devastated by war or invasion challenge urban planners. Resources are scarce. The existing population has needs. Buildings, roads, services and basic infrastructure like power, water and sewerage are often damaged, but with salvageable parts. 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 of rubble and desolation. Despite this, the indigenous population continues to live in the area, constructing makeshift homes and shops out of salvaged materials. Any reconstruction plan, such as Hisham Ashkouri's City of Light Development, needs to be sensitive to the needs of this community and its existing culture and businesses.

Urban Reconstruction Development plans must also work with government agencies as well as private interests to develop workable designs.

Transport

Main article: Transportation planning

Very densely built-up areas require high capacity urban transit, and urban planners must consider these factors in long term plans (Canary Wharf tube station).

Although an important factor, there is a complex relationship between urban densities and car use.

Transport within urbanized areas presents unique problems. The density of an urban environment increases traffic, which can harm businesses and increase pollution unless properly managed. Parking space for private vehicles requires the construction of large parking garages in high density areas. This space could often be more valuable 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 are low density. Ratios above five constitute very high density. Most exurbs are below two, while most city centres 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 higher densities to reduce per-capita infrastructure costs. 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 centres, 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.^{[citation needed]}

Problems can often occur at residential densities between about two and five.^[30] 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 2% ridership.^[31]

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.

Economics

Main article: Urban economics

Suburbanization

Main article: Suburbanization

Low (auto-oriented) density suburban development near Colorado Springs, Colorado, United States

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

Main article: Environmental planning

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 and microclimate. In Europe this process is known as a 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 focus now on smaller and larger systems of resource extraction and consumption, energy production, and waste disposal. A practice known as Arcology 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^{[citation needed]}.

An urban planner can 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.^[32] 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.

Tall buildings in particular can have a substantial effect in channelling winds and shading large areas. The microclimate around the building will typically be assessed as part of the environmental impact assessment for the building. The placement and design of buildings may also be affected by the land on which they are placed. Soil and rock considerations such as depth to bedrock may influence the height of very tall structures, as in Manhattan, though there is less impact than previously supposed,^[33] and geological conditions such as fault lines may affect building requirements. See: Geotechnical engineering.

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 Hong Kong's Kowloon and Central.

In urban planning, sound is usually measured as a source of pollution. Another perspective on urban sounds is developed in Soundscape studies emphasising that sound aesthetics involves more than noise abatement and decibel measurements. Hedfors^[34] coined 'Sonotope' as a useful concept in urban planning to relate typical sounds to a specific place.

Light pollution has become a problem in urban residential areas, not only as it relates to its effects on the night sky, but as some lighting is so intrusive as to cause conflict in the residential areas and paradoxically intense improperly installed security lighting may pose a danger to the public, producing excessive glare. The development of the full cutoff fixture, properly installed, has reduced this problem considerably.

Process

Blight may sometimes cause communities to consider redeveloping and urban planning.

Prior to the 1950, Urban Planning was seldom considered a unique profession.^[35] Planning focused on top-down processes by which the urban planner created the plans. The planner would know architecture, surveying, or engineering, bringing to the town planning process ideals based on these disciplines. They typically worked for national or local governments.

Changes to the planning process Strategic Urban Planning 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.^[36] The term advocacy planning was coined by Paul Davidoff in his influential 1965 paper, "Advocacy and Pluralism in Planning" which acknowledged the political nature of planning and urged planners to acknowledge that their actions are not value-neutral and encouraged minority and under represented voices to be part of planning decisions.^[37]

Ozawa and Seltzer (1999) advocate a communicative planning model in education to teach planners to work within the social and political context of the planning process. In their paper "Taking Our Bearings: Mapping a Relationship among Planning Practice, Theory, and Education," the authors demonstrate the importance of educating planners beyond the rational planning model in which planners make supposedly value-neutral recommendations based on science and reason. Through a survey of employers, it was found that the most highly rated skills in entry-level professional hiring are communication-based. The results suggest this view of planning as a communicative discourse as a possible bridge between theory and practice, and indicate that the education of planners needs to incorporate synthesis and communication across the curriculum.^[38]

Developers have also played huge roles in development, particularly by planning projects. 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 Docklands, for example, was largely an initiative pushed by private developers 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 those of plants. They say that urban planning should thus take its cues from such natural processes.^[39] Such theories also advocate participation by inhabitants in the design of the urban environment, as opposed to simply leaving all development to large-scale construction firms.^[40]

In the process of creating an urban plan or urban design, carrier-infill is one mechanism of spatial organization in which the city's figure and ground components are considered separately. The urban figure, namely buildings, are represented as total possible building volumes, which are left to be designed by architects in following stages. The urban ground, namely in-between spaces and open areas, are designed to a higher level of detail. The carrier-infill approach is defined by an urban design performing as the carrying structure that creates the shape and scale of the spaces, including future building volumes that are then infilled by architects' designs. The contents of the carrier structure may include street pattern, landscape architecture, open space, waterways, and other infrastructure. The infill structure may contain zoning, building codes, quality guidelines, and Solar Access based upon a solar envelope.^[41][42] Carrier-Infill urban design is differentiated from complete urban design, such as in the monumental axis of Brasília, in which the urban design and architecture were created together.

In carrier-infill urban design or urban planning, the negative space of the city, including landscape, open space, and infrastructure is designed in detail. The positive space, typically building site for future construction, are only represented as unresolved volumes. The volumes are representative of the total possible building envelope, which can then be infilled by individual architects.

See also

• Index of urban planning articles
• Index of urban studies articles
• List of planned cities
• List of urban planners
• List of urban theorists

Notes

1. ^ http://www.environment.uwaterloo.ca/planning/index.html
2. ^ Grogan, Paul, Proscio, Tony, Comeback Cities: A Blueprint for Urban Neighborhood Revival, 2000. ISBN 0-8133-3952-9
3. ^ ^{a b} Davreu, Robert (1978). "Cities of Mystery: The Lost Empire of the Indus Valley". The World’s Last Mysteries. (second edition). Sydney: Readers’ Digest. pp. 121-129. ISBN 0-909486-61-1.
4. ^ Kipfer, Barbara Ann (2000). Encyclopedic Dictionary of Archaeology. (Illustrated edition). New York: Springer. p. 229. ISBN 306461587.
5. ^ ^{a b} Jackson, Kenneth (1985). Crabgrass Frontier: The Suburbanization of the United States. Oxford University Press. pp. 73–76. 
6. ^ Vitrivius (1914). The Ten Books on Architecture, Bk I. Harvard University Press. 
7. ^ Siegfried Giedion, Space, Time and Architecture (1941) 1962, in reference to an air view (fig.8) of the medieval Italian town of Bagnocavallo. Giedion's source was Luigi Piccinati, "Urbanistica Medioevale" in Urbanistica deal Antichità ad Oggi (Florence 1943).
8. ^ Siegfried Giedion, Space, Time and Architecture (1941) 1962 p 43.
9. ^ The undulating terrace of housing makes its appearance surprisingly late: Giedion's example is Lansdown Crescent, Bath, 1794; Giedion 1962, fig. 83.
10. ^ Smith, Michael E. (May 2005). "City Size in Late Post-Classic Mesoamerica" (PDF). Journal of Urban History (Beverley Hills, CA: SAGE Publications) 31 (4): 403–434. doi:10.1177/0096144204274396. OCLC 1798556. http://www.public.asu.edu/%7Emesmith9/1-CompleteSet/MES-05-CitySize.pdf. Retrieved 2008-02-01. 
11. ^ Girouard, Mark, Cities and People, 1985, London, p. 285.
12. ^ Busquets, Joan Barcelona, the urban evolution of a compact city, 2005, ISBN 88-8447-204-0, Harvard University, p. 122.
13. ^ Hall, Peter et al. Sociable Cities; the legacy of Ebeneezer Howard, 1998, ISBN 0-471-98504-X, John Wiley & Sons, New York.
14. ^ ^{a b} Smith Morris et al. British Town Planning and Urban Design, 1997, ISBN 0-582-23496-4, Longman, Singapore.
15. ^ ^{a b c} Wheeler, Stephen (1998). Planning Sustainable and Livable Cities. New York: Routledge. ISBN 0-415-27173-8. 
16. ^ Oregon Ballot Measures 37 (2004) and 49 (2007)
17. ^ [Gesellschaft für Technische Zusammenarbeit (GTZ)Zopp An introduction to the Method. Eschborn. Germany (1988)]
18. ^ B.Muller, S.Curwell, J. Turner: Model for the improvement of LUDA development of collaborative strategic goal oriented programming in Urbanistica Dossier n.74 INU Edizioni Italia (2205)
19. ^ Luda Project
20. ^ Innes, Judith; Booher, David (2000). "Public Participation in Planning: New Strategies for the 21st Century". Working Paper 2000-2007 (University of California, Berkeley: Institute of Urban and Regional Development). http://escholarship.org/uc/item/3r34r38h. 
21. ^ Shandas, Vivek; Messer, W. Barry (2008). "Fostering Green Communities Through Civic Engagement, Community-Based Environmental Stewardship in the Portland Area". JAPA 74 (4): 408–418. doi:10.1080/01944360802291265. 
22. ^ Sirianni, Carmen (2007). "Neighborhood Planning as Collaborative Democratic Design, The Case of Seattle". JAPA 73 (4): 373–387. doi:10.1080/01944360708978519. 
23. ^ New Zealand Herald: Tensions spill over in billboard row
24. ^ Christopher Alexander, A Pattern Language, Towns Buildings, Construction
25. ^ "City Planning". An article on Jane Jacobs. http://www.herdmycattle.com/city-planning/. 
26. ^ George L. Kelling, Catherine M. Coles, Fixing Broken Windows: Restoring Order And Reducing Crime In Our Communities
27. ^ Reinventing planning: A new governance paradigm for managing Human settlements, Commonwealth Association of Planners
28. ^ The Christian Science Monitor: Kenyans buy into slum plan, 26 May 2004
29. ^ Urban Sores: On the Interaction Between Segregation, Urban Decay, and Deprived Neighbourhoods By Hans Skifter Andersen. ISBN 0-7546-3305-5. 2003.
30. ^ Stewart Brand, How Buildings Learn
31. ^ Transportation Efficient Land Use- Municipal Services and Research Center of Washington, Accessed 09nov09, says that each 40% increase in density reduces trips by 20-30%.
32. ^ C. Michael Hogan, Analysis of highway noise, Journal of Water, Air, and Soil Pollution, Volume 2, Number 3, Biomedical and Life Sciences and Earth and Environmental Science Issue, pages 387-392, September, 1973, Springer Verlag, Netherlands ISSN 0049-6979
33. ^ Jason Barr and Jeffrey P. Cohen, [www.aeaweb.org/aea/2011conference/program/retrieve.php?pdfid=352 "Why are Skyscrapers so Tall? Land Use and the Spatial Location of Buildings in New York"], December 2010
34. ^ 2003 Site Soundscapes - Landscape Architecture in the Light of Sound - Per Hedfors (ISBN 91-576-6425-0) - book & CD-Rom
35. ^ Hodge, Gerald and Gordon, David Planning Canadian Communities (fifth edition), Nelson College Indigenous, 2007
36. ^ Forester John. "Planning in the Face of Conflict", 1987, ISBN 0-415-27173-8, Routledge, New York.
37. ^ http://www.plannersnetwork.org/publications/2007_spring/angotti.htm
38. ^ Ozawa, C.P., Seltzer, E.P.(1999). "Taking our bearings: Mapping a relationship among planning practice, theory and education". Journal of Planning Education and Research. 18: 257-266.
39. ^ "Life and the geometry of the environment", Nikos Salingaros, November 2010
40. ^ "P2P Urbanism", collection of articles by Nikos Salingaros and others.
41. ^ Capeluto, I. H. and Shaviv, E. On the Use of 'Solar Volume' for Determining the Urban Fabric. Solar Energy Vol. 70, No. 3, pp. 275-280, 2001.
42. ^ Nelson, Nels O. Planning the Productive City, 2009, accessed December 30, 2010.

References

• Atmospheric Environment Volume 35, Issue 10, April 2001, Pages 1717-1727. "Traffic pollution in a downtown site of Buenos Aires City"
• Garvin, Alexander (2002). The American City: What Works and What Doesn't. New York: McGraw Hill. ISBN 0-07-137367-5.  (A standard text for many college and graduate courses in city planning in America)
• Hoch, Charles, Linda C. Dalton and Frank S. So, editors (2000). The Practice of Local Government Planning, Intl City County Management Assn; 3rd edition. ISBN 0-87326-171-2 (The "Green Book")
• T. R. Oke (1982). "The energetic basis of the urban heat island". Quarterly Journal of the Royal Meteorological Society 108: 1–24.
• Matheos Santamouris (2006). Environmental Design of Urban Buildings: An Integrated Approach.
• Tunnard, Christopher and Boris Pushkarev (1963). Man-Made America: Chaos or Control?: An Inquiry into Selected Problems of Design in the Urbanized Landscape, New Haven: Yale University Press. (This book won the National Book Award, strictly America; a time capsule of photography and design approach.)
• Wheeler, Stephen (1998). "Planning Sustainable and Livable Cities", Routledge; 3rd edition.

Further reading

• Urban Planning, 1794-1918: An International Anthology of Articles, Conference Papers, and Reports, Selected, Edited, and Provided with Headnotes by John W. Reps, Professor Emeritus, Cornell University.
• City Planning According to Artistic Principles, Camillo Sitte, 1889
• Tomorrow: A Peaceful Path to Real Reform, Ebenezer Howard, 1898
• The Improvement of Towns and Cities, Charles Mulford Robinson, 1901
• Town Planning in practice, Raymond Unwyn, 1909
• The Principles of Scientific Management, Frederick Winslow Taylor, 1911
• Cities in Evolution, Patrick Geddes, 1915
• The Image of the City, Kevin Lynch, 1960
• The Concise Townscape, Gordon Cullen, 1961
• The Death and Life of Great American Cities, Jane Jacobs, 1961
• The City in History, Lewis Mumford, 1961
• The City is the Frontier, Charles Abrams, Harper & Row Publishing, New York, 1965.
• A Pattern Language, Christopher Alexander, Sara Ishikawa and Murray Silverstein, 1977
• What Do Planners Do?: Power, Politics, and Persuasion, Charles Hoch, American Planning Association, 1994. ISBN 978-0-918286-91-8
• Planning the Twentieth-Century American City, Christopher Silver and Mary Corbin Sies (Eds.), Johns Hopkins University Press, 1996
• "The City Shaped: Urban Patterns and Meanings Through History", Spiro Kostof, 2nd Edition, Thames and Hudson Ltd, 1999 ISBN 978-0-500-28099-7
• The American City: A Social and Cultural History, Daniel J. Monti, Jr., Oxford, England and Malden, Massachusetts: Blackwell Publishers, 1999. 391 pp. ISBN 978-1-55786-918-0.
• Urban Development: The Logic Of Making Plans, Lewis D. Hopkins, Island Press, 2001. ISBN 1-55963-853-2
• Readings in Planning Theory, Susan Fainstein and Scott Campbell, Oxford, England and Malden, Massachusetts: Blackwell Publishers, 2003.
• Urban Planning Theory since 1945, Nigel Taylor, London, Sage, 2007

External links

• Urban and Regional Planning at the Open Directory Project