According to a United Nations survey by 2050, 68% of the world's population will live in urban areas or in cities with a high concentration of inhabitants and infrastructure built to serve them. This leap to cities is expected to occur mainly in Asia and Africa, two regions whose level of urbanization is now below average. However, China, India, and Nigeria are rapidly expanding both in terms of population and development. As the demand for services increases, the number of urban agglomerations also increases as a result. These are not only cities, but also megacities: by 2030, 43 megacities are expected to be built, each with more than 10 million inhabitants. Considering that about 4 million inhabitants live in the metropolitan city of Rome, 3 million in Milan, and 8 million in London, we must try to imagine rather cities like Tokyo, Shanghai and New Delhi.
Urbanization involves many problems: the urban waste management, the construction of wastewater plants and the need to find suitable housing for everyone could pose a big challenge for compliance with the Sustainable Development Goals. For this reason, the development of green (or blue-green) infrastructures is accelerating. The goal behind the construction of these facilities is not only to preserve the environment in large cities, but also to offer solutions for all citizens, addressing poverty and social exclusion at the same time. A sustainable megalopolis complies with three parameters: it is ecological, i.e. based on respect for the environment and its evolution is monitored every time a settlement expands; it is technological, i.e. advanced technologies are used in the construction of infrastructures and an innovative approach to urban planning; it is social, i.e. based on the respect and involvement of all social categories living in the urban environment, avoiding the creation of slums or segregation phenomena (even accidental).
Coastal cities are more frequently under investigation as the fastest growing cities are almost all on the sea. They are at risk of flooding due to rising sea levels and have clear boundaries for expansion. They also have problems concerning the polluted water or the discharge of waste into the sea.
Inland and coastal areas have in common two pressing issues: one is the improvement of the connection between different green areas with the aim of lower the air and soil temperature, guaranteeing at the same time universal access to parks and gardens; the second one is the creation of good drainage systems to prevent the flooding caused by excessive rainwater or seawater infiltrated into cities. This means that all human settlements must be built around green areas and not just in the city center. If there are natural water sources such as rivers and streams, these must not be redirected or blocked, but instead used as water resources by building adequate systems for rainwater management around them.
Some ideas for sustainable urban planning are the use of vertical gardens, shared gardens, aquaculture, and urban farms where permitted. Outside cities, it is necessary to preserve the characterizing environments of the specific region such as forests, meadows and plains, paying attention to the maintenance of the tricky balance between animal and human life. Allowing the growth of vegetation within urban and suburban areas is also important for two reasons: this avoids the creation of a hot and sultry microclimate and at the same time it helps to fight pollution, to save on energy by decreasing the need for air conditioning, to create an aesthetically pleasing environment, to reduce stress by offering areas in which to relax and to promote sporting activities. This also impacts on reducing the level of "environmental inequality" and social exclusion. This type of urban planning requires high levels of attention from local governments and specific laws, as well as civic participation, in order to understand the needs and demands of the inhabitants. Poorer communities usually suffer from denied access to services such as quality food, green areas, and clean air. By properly planning cities, it is not impossible to provide such facilities to every neighborhood.
In addition to being energy efficient and green, the sustainable urban environment must be comfortable for citizens. In addition to being energy efficient and green, the sustainable urban environment must be comfortable for citizens. This could be possible by ensuring a good public transport network, bicycle and pedestrian lanes (the importance of a “walkable” city is often underestimated), gas stations for electric cars and efficient systems for recycling waste. As already mentioned, citizens should not only to make proposals but also to offer solutions. An excellent example is given by L'Aia which, through a pointscollection, is rewarding citizens who remodel their homes implementing green restructuring interventions. Everyone is pushed to do something that, even if small, can be meaningful.
Green urbanism is a present-day challenge which, if correctly managed, will lead to the raising of living standards in large cities and will provide an important example for the development of new megacities.
Translated by Simona Taravella
Nadia Dalla Gasperina
Nadia Dalla Gasperina è studentessa di scienze politiche all’Università di Bologna, dove si occupa di Balcani. Il suo interesse per la diplomazia, le relazioni internazionali, e l’azione civile l’hanno portata a collaborare con diverse associazioni e organizzazioni in Italia e all’estero. Scrive ora nella sezione Ambiente e Sviluppo di MI Post.