Economist Steven Sheppard and CLEAR institute have estimated that based on the current pattern of development with peripheral development and of urbanized land- the built up area of the developing country cities will increase from 2000 sq.km to 600,000 sq.km in 2030. The reality of this ‘pressure’ of development is directly going to be on the resources that our cities are dependent on, its judicious use and equitable distribution.
This ‘Sustainable Ecological Urbanism’ observes cities as ‘Systems’. At present the city system is ‘parasitic’ that disrupts the natural earth and it produces a deteriorating quality of life for all inhabitants. Cities are not self-sustaining resource systems like natural eco-system. The land area of cities comprise only a tiny fraction (typically much less than 1%) of the total area of productive ecosystem required to sustain the needs of urban human population (Source: Bill Rees).
However, the solution still lies in this city-system where cities need to optimize their production, resilience and expansion metabolism through spatial rearrangements. Each city has a different pattern of energy use which cumulatively creates the city’s metabolism. These patterns are associated with economic development but more importantly with forms of urbanism and other city building approaches. City’s infrastructure, physical layout and urban forms give structure to urban energy and the CO2 metabolism of not just day to day but over the life cycle of the city.
Sustainable urban form implies an inter-linkage of sound environmental, social and economic foundations. It considers the principal elements of urban form – land use patterns, position/ transport infrastructure, density and characteristics of the built environment.
Lynch (1981) considers five basic dimensions for the performance dimensions of the spatial form of a city. These are:
§ How settlement form affects vitality,
§ How settlement form affects human sense,
§ The degree to which the settlement form fits the requirements of people,
§ How able people are to access activities, services etc, and
§ How much control people have over services/ activities/ spaces etc.
The two Models of Urban Form:
The urban form has two principal alternatives.
§ A high density, mixed use centralized urban form.
§ S low density, dispersed urban form often dependent on Automobile.
Compact high density mixed use transit driven Urban Form
Arguments in favour of a compact, centralized city claim that this type of urban form provides environmental, social and economic benefits. The environmental benefits of a compact urban form are seen to include reduced energy usage and greenhouse gas emissions following a lesser demand for polluting modes of travel, reduced pressure on greenfield sites and greater use of more efficient technologies. The promulgated social benefits of a compact urban form include a greater availability of housing that meets peoples’ needs in a sustainable way, increased access to services and facilities leading to better quality urban environments. Mixed land use is the most sustainable type of urban use, in that it increases the viability of services and transport provision supported by high residential density. Mixed land use in this context refers to the intermingling of land uses to ease access and reduce travel. Economically, it is argued that a compact urban form can lead to new business formation and innovation, which also attracts new residents
Decentralized, low density dispersed urban form
Another argument states that a compact city may mean a reduction in environmental quality through the loss of open spaces to development. There is potential for diseconomies to occur when the central structure becomes too big (e.g. congestion externalities). In terms of residential preferences, a compact high density urban form may be less desirable for some individuals. Households with children may prefer to locate further away from the city centre, where they have a garden. Other households may experience an increase in income and demand more space, which is found in less dense developments, further away from the city centre. The compact city can also fail to adequately consider future changes in population. A high density, compact city is less likely to be able to cope with significant population growth, as there is less potential for expansion if development is already at a high density. Proponents of the decentralized view therefore stress either the benefits of a decentralized ‘rural’ or ’semi-rural’ life style with low development costs or the unstoppable market forces that will create dispersed communities with low energy consumption and congestion.
Evolving Sustainable Urban form for Indian Cities
Historic Indian cities were compact, pedestrianised, mixed use developments that at present are under threat of decay due to poor management and lack of infrastructure. Compact cities are not new to the Indian mind, but for compact cities are to deliver sustainable outcomes, they have to be well managed.
It is blatantly clear that simply increasing densities and mixing uses will not lead to sustainable outcomes. High quality infrastructure needs to be provided, public transport needs to be well managed, affordable and reliable, noise and air pollution have to be maintained at acceptable standards, basic services such as water, drainage and electricity need to be provided, and levels of public facilities such as health care and education have to be appropriate for the high numbers of city dwellers. Furthermore, urban environments have to be kept clean, safe and ‘livable’. Even in developed countries that have good basic infrastructure, these standards are hard to achieve; in developing countries it may be more challenging. As Burgess states:
‘High demographic growth, low levels of economic development, high income inequalities, small urban budgets and shortages of environmental infrastructure, shelter and basic services have a critical effect on densification policies and the effectiveness of policy instruments.’
The question therefore is towards finding the sustainable urban form for Indian cities. Whenever urban compaction and intensification is not a solution, with Indian cites of high density, high urbanization rate, high proportions of informal developments, lack of infrastructure and urban management problems might find a solution in ‘Polycentric City’ or the ‘Linear Transport Oriented’ model. Another possibility is to make compact city models work in Indian cities with renewal strategies, infrastructural inserts and proper urban management. Further all cites shall need to evolve urban form through participatory methods with stress on environment resource management, community development etc.
Urban Form: The case of Indian Cities
Population of Ahmedabad: 45.14 lakh in 350 sq.km. in 2001, 65 lakh in 500 sq.km. by 2010
Ahmedabad can boast to be a ‘Compact City’ wherein the city during the past ten-year period has expanded in a contiguous manner and remained compact and new development measures are also directed to promote the city on the principles of compact city. This has been ensured by initiatives such as
§ Integrated Land Use Transport Development: Development of Metro rail, Regional Rail and the successful
Bus Rapid Transport System
§ Planning initiatives such as Town Planning Scheme with insitu redevelopment, reconfiguration of old
§ Slum networking with provisions of basic physical and social infrastructure, already implemented in 45 slums
§ Environmental management with projects such as Sabarmati Riverfront development.
Mumbai is city of paradoxes, with a high migration rate 54% of the population lives in about 1950 ‘slums’ which are located both on public and private land. The city has issues such as 2-6 hours of water supply, poor condition of transmission and distribution system, 35% of household without sanitation, old storm water drainage network, average travel speed f 6-8 kms per house, limited drainage capacity, overburden on mass transit rail system and immense decline in quality of life.(Source: Mumbai CDP).
Initiatives are directed in Mumbai for improving its transport efficiency with promotion of Metro rail, east-west road corridor developments etc. Other initiative is towards increase in FSI for renewal and upgradation activities for slums such as Dharavi as well as old vacant mill areas.
Delhi is growing at a rate much higher than any Indian city with over 47% decadal growth from 1991-2001, more than double of the national rate. Density of population is higher among all states with 9,340 person per sq.km in comparison to an all India level of 324 person per sq.km in 2001 and the population of Delhi is expected to be 24 million by 2021. Realities such as these have caused huge disparity in Delhi. Various projects initiated in the city are directed towards, Sustainable transport with advent of successful Metro system, conflicted BRTS and new proposed integrated landuse transport development. Further initiatives are towards housing, slum improvement, redevelopment and renewal of historic stagnated city domains, environmental management with initiatives of developing Yamuna water front, conceptual projects for conservation of the Delhi ridge system.
Home to almost 6 million people, and a base for 10,000 industries, Bangalore is India’s fifth largest city and the fastest growing city in Asia. This city is the largest contributor to India’s 12.2 billion USD turnover.. Today the growth is not confined to the city but has spread beyond, into Bangalore Metropolitan Region. This growth offers great opportunities – increased revenue, employment, industrialization, tourism etc.The challenge is to manage this growth and associated change in the most sustainable way in order to protect and enhance the quality of life. The Revised Master Plan 2015 projects the urban population at 8.8 million by 2015 over an area of 1306 Sq. Km and much of the physical infrastructure is a century old. Public housing is short of supply and private housing is often out of reach; residential localities have sprung up without sufficient lung spaces; aging water and power systems are in need of upgrades and roads are congested and unsafe; environmental degradation is alarming.The Bangalore Metro Rail system, consisting of double line north-south and east-west corridor and Bangalore-Mysore Infrastructure Corridor (BMIC) are some of the upcoming massive infrastructure projects.
There can never be a generalized blue print for a urban form towards making our cities sustainable and livable. All efforts would be laden in planning, design, form, technology, infrastructure layout, business models, management, partnership and behavior. These solutions are to be evolved, keeping in mind the specificity of our own cities. Important lesson can be learnt from the case example of Curitiba.
Curitiba: Not just Bus Transit System
The sustainable form of Curitiba has evolved due to its own realities. Cited in the book by Jeb Brugmann – Urban Revolution is one such episode of evolvement of the city. It cites the ecological flood control system of Barigui River in the city where ecological methods were incorporated due to lack of available funds required for a concretizing approach, and instead evolving protected river corridors, forming chain of flood water collection basins with chains of lakhs and percolating water through a ‘graveled’ park. The initiative though was towards controlling major floods in the city, it was linked one by one like a thread to various other dimensions. The graveled park and chains of lakes served as necessary open spaces raising the level of green space per person from then 2 sq ft per person to 170 sq.ft. in 1990s. Further, the whole spine was utilized for more participatory activities such as waste collection, encouraging use of public transit system, recreational development, participatory developments wherein the children of nearby slums took management activities by themselves in this spine. As a result the development evolved with multiple complimentary purposes as a ‘Recreational-Social-Cultural-Educational-Ecological-Disaster Management System’.