South Asia is experiencing rapid urbanization, with five of its cities projected to be among the largest in the world by 2015. This growth is driven by rural-to-urban migration as people seek economic opportunities. However, many migrants end up living in slums lacking basic services. The region's megacities face challenges like sprawling slums, poverty, disease, pollution and lack of infrastructure. Dhaka has experienced extreme population growth and now has over 12 million residents, with many living in poor conditions. Other large and growing South Asian cities discussed are Mumbai, Delhi, and Karachi. Effective solutions are needed to manage urban growth and improve living standards in a sustainable manner.

1. Introduction:
South Asia is undergoing a rapid process of urbanization. In 1950 there was only one large city-
Kolkata, which was among the top ten cities in the world. In 2000 four of the largest 15 cities of
the world were situated in South Asia. By 2015 five of the largest cities will be from this region.
These cities have swollen up through migration from the countryside and many of these
migrants are poor. In the backdrop of massive wealth of these cities the poor lead a subhuman
life in slums or squatters, in its informal economy and in its underworld without shelter, safe
water or medicare and often jobs.
Definition of Mega city:
A megacity is generally defined as a metropolitan area with a total population in excess of 10
million people.A mega city can be a single metropolitan area or two or more metropolitan areas
that converge. The terms conurbation, metropolis and metroplex are also applied to the latter.
Changing pattern of mega city:
• In 1950s and 1960s the world’s largest cities were in developed countries
• In the 1970s, several Latin American megacities emerged
• From 1960 to 1990 a few developed world megacities, such as London, actually saw
population decline due to deindustrialisation and counter-urbanisation
• Since 1990 megacity growth has been centred on Asia, and especially India and China
since the turn of the millennium
• Africa has relatively few megacities although many African cities are growing rapidly
• In the 80s ‘megacity’ referred to cities of over 5 million
people.
• In the late 90s, the 8 million definition became common.
• Today 10 million is often used.

3. Nature and Challenges of South Asia mega cities
• Sprawling slums
• High degree of informal housing informal economy
• Growing urban unrest and conflicts
• Corruption , bribery, cronyism
• Growing socio-economic disparities
• Explosive population growth
• Poverty and prevalence of informal economy
• Lack of clean water and sanitation
• Disease epidemics
Growth rates, 1950-2015, of 21 urban agglomerations that are
expected to be megacities in 2015
Source: United Nations, World Urbanization Prospects: The 2001 Revision. Data Tables and Highlights
Average annual growth rate (percentage)
Urban
agglomeration
Country
Population
2015
(000s) 1950-75 1975-2000 2000-15
Tokyo Japan 27,190 4.2 1.2 0.2
Dhaka Bangladesh 22,766 6.6 7.0 4.0
Mumbai India 22,577 3.6 3.1 2.3
São Paulo Brazil 21,229 5.6 2.2 1.1
Delhi India 20,884 4.6 4.1 3.5
Mexico City Mexico 20,434 5.2 2.1 0.8
New York USA 17,944 1.0 0.2 0.5
Jakarta Indonesia 17,268 4.8 3.3 3.0
Calcutta India 16,747 2.3 2.0 1.7
Karachi Pakistan 16,197 5.4 3.7 3.2
Lagos Nigeria 15,966 7.5 6.1 4.1
Los Angeles USA 14,494 3.2 1.6 0.6
Shanghai China 13,598 3.1 0.5 0.4
Buenos Aires Argentina 13,185 2.4 1.1 0.6
Metro Manila Philippines 12,579 4.7 2.8 1.6
Beijing China 11,671 3.1 1.0 0.5
Rio de Janeiro Brazil 11,543 4.0 1.2 0.5
Cairo Egypt 11,531 3.7 1.8 1.3
Istanbul Turkey 11,362 4.8 3.6 1.6
Osaka Japan 11,013 3.5 0.4 0.0
Tianjin China 10,319 3.8 1.6 0.8
Note: Urban agglomerations are ordered according to population in 2015.

4. • Transport gridlock
• Urban funding crises
• Overcrowding
• Lack of green space
• Pollution of air and water
• Gating and segregation
• Visual and noise pollution
• Water supply problems
• Deep eco-footprints
• Declining centres
• Sprawling suburbs and exurbs
• parasites all are challenge
• Access to employment – formal and informal employment
• Provision of Shelter and housing – rise of squatter settlements/slums; upgrading
housing; new housing projects
• Water and sewage provision and waste disposal
• Health and Nutrition issues –unclean water, vermin, dangerous housing and utility
connections,
• Air Water and Noise Pollution
• Congestion and Provision of Transport Infrastructure
• Civil unrest
• Traffic congestion
• Political fighting
• Lack of basic sanitation
geo-ecological change:
• e.g. through natural hazards, air-, water- and soil pollu-tion, sea-level rise, global
warming, urban heat islands, bio-connection.

5. geo-economic change:
• e.g. through economic globalisation, industrial competi-tion, activities of transnational
companies, new labour division, transformation processes
geo-social change:
• e.g. through (inter)national migration, empowerment of marginalised groups, urban
ethnicity, new urban epidemics, global life styles
geo-cultural change:
• e.g. through organisation of global places, globalised media, social movements, new
cultural diversity, transnational social scapes.
geo-political change:
• e.g. through conflicts and power (im)balances, globally acting NGO networks, human
rights movements, global regulation, security and stability
Causes of mega city in south Asia:
• High birth rates in less developed countries
• Migration of the rural poor into the city
• The countryside has no land left to farm
• City offers the possibility of jobs, schools, and a better way of life
o Industrialization
o Economic opportunity
o job opportunities
o Health services
o Education opportunities
o Higher quality of life
o Communication and transport
o Trade and commerce
o Higher security

6. South Asia mega city:
Dhaka:
Dhaka, the capital of Bangladesh, is the city with the highest population growth in the world.
About 28% of the population is poor. Some 3.4 million live in slums. Close to one third don’t
have access to sanitation. Watch the challenges facing Dhaka as it population continues to
grow.With 12 million residents, Dhaka is the 11th
largest city in the world
Population Explosion of Dhaka Mega city:
Source: World Urbanization prospects: The 2003 revision, UN

10. Karachi, Pakistan
Urban Detail — After Pakistan won independence from the British and separated from India
Karachi’s population increased hugely as hundreds of thousands of Muslim migrants from India
settled there, transforming its demographics and economy. (Source: Reuters)
Mumbai, India
Mumbai–called Bombay until the name was changed in 1995–is the commercial and movie
capital of India and has attracted millions of migrants from the countryside. With high birth rates
and the continued influx of migrants, Mumbai’s population is expected to grow rapidly in the
future.
Urban Detail — Over half of the city’s population lives in slums. Poor infrastructure and
widespread poverty make it very difficult to meet the demands of an ever-growing population.
(Source: Reuters)
Delhi, India

11. Delhi is India’s capital and recently overtook Mumbai as the biggest city by population size. It’s
a place of striking contrasts. Mosques, bazaars, and narrow lanes mark the old town. New Delhi,
the capital, features grand boulevards, business centers, and shopping malls.
(Source: Shutterstock)
Conclusion:
The diversity of megacities means that a challenge in one city can mean something different for another
city. Every city is unique, so solutions need to be tailored to fit. New urban-planning models are
required, and it is important for city leaders to find a balance between economic growth, environmental
considerations and quality of life.