Why are megacities concentrated in the developing world, and what challenges do they face?
Analyse the growth, characteristics and challenges of megacities in the developing world
A focused WACE Year 12 Geography answer on developing-world megacities. Covers what a megacity is, why they cluster in the developing world, informal settlements and services, and liveability challenges with real examples such as Dhaka and Lagos.
Reviewed by: AI editorial process; not yet individually human-reviewed
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What this dot point is asking
SCSA wants you to define megacities, explain why they cluster in developing countries, describe their characteristics, and analyse the challenges they pose for liveability and planning. A strong answer uses a named megacity in depth.
What is a megacity
Megacities such as Tokyo, Delhi, Shanghai, Dhaka, Lagos, Mumbai and Sao Paulo concentrate enormous populations, economic activity and political power.
Why megacities cluster in the developing world
Earlier waves of urbanisation produced large cities in the developed world, but growth there has slowed. Today the fastest growth is in developing countries, driven by high rural-urban migration combined with high natural increase. Because these cities grow far faster than industry and infrastructure, populations swell before the jobs, housing and services to support them exist.
Many developing megacities are also primate cities that dominate their national economy, which concentrates migration even further into a single centre.
Characteristics and challenges
- Informal settlements
- Because formal housing cannot keep pace, large shares of residents live in informal settlements, sometimes called slums, often lacking secure tenure, clean water and sanitation.
- Infrastructure strain
- Water, electricity, waste and transport systems are overwhelmed, producing congestion, pollution and disease risk.
- Employment
- Many work in the informal economy, in insecure, low-paid jobs without protection.
- Environmental hazard
- Rapid, unplanned growth often pushes settlement onto floodplains and unstable slopes, raising disaster risk, which climate change intensifies.
Opportunities as well as problems
Megacities are not only problems. They generate the bulk of national economic output, offer migrants real gains over rural poverty, and concentrate the talent and density that drive innovation. Informal settlements often contain vibrant economies and strong communities. A balanced answer recognises megacities as engines of opportunity that nonetheless face severe and urgent planning challenges.
This dot point sets up the management strategies examined elsewhere in Unit 4, where responses such as upgrading informal settlements, investing in mass transit and decentralising growth are evaluated.