The growth of megacities around the world creates both opportunities and threats
From now until 2050 megacities will become more common and the challenge lies in building them. Megacities are cities with a population of more than 10 million people. There are currently 23 megacities with this number set to rise to 37 by 2025. As the number of megacities increases, there is an urgent need to build these cities sustainably to protect the future inhabitants.
In 1900, London was the world’s largest city with a population of 6.5 million. During the 20th century, there has been mass migration into cities across the world as they pulled people in with the hope of jobs and better opportunities.
Greater Tokyo is today’s largest city with a population of 37 million. It is predicted to stay the largest city until 2025 but other megacities are emerging and are set to overtake Tokyo by 2050 such as Mumbai, Mexico City and Lagos.
Caution must also be taken in building these megacities given climate change and the fact that 90% of urban areas are built in coastal areas
There are huge pressures on these megacities to house and create the basic living needs for their occupants. Currently, one in three people who live in urban areas worldwide live in slums, so have a lack of access to basic sanitation. As these megacities continue to grow, there is the need for huge infrastructure to be built to accommodate the continued influx of people. Improving living conditions for these people over the coming decades will be a huge challenge.
Caution must also be taken in building these megacities given climate change and the fact that 90% of urban areas are built in coastal areas. Sea level rises and more extreme flooding events will pose a real risk here. Therefore, there is the need to ensure megacities are resilient and do not put the future inhabitants unnecessarily at risk.
Technology, innovation and experience will all need to be applied and floating cities or cities on stilts could be the future for megacities such as Dhaka or Lagos.
If these cities are to become sustainable then they need to be built using experience of design and engineering practices coupled with expertise of the local cultural and population needs. This is where there is the opportunity for international expertise, including the UK construction industry, to support the development and design of these cities.
The short-term needs of the inhabitants should be coupled with the long term vision to create places that withstand or adapt to future pressures. There is where the UK along with other international partners can provide expertise to help transfer knowledge to build the sustainable cites of the future.
Louise Clarke chairs the 2025 Group and sits on the Construction Industry Leadership Council