​African cities like Los Angeles

Look at Los Angeles: For a long time now, California's largest metropolitan area has not had enough water resources. It gets its water from the Sierra Nevada, nearly 600 kilometers (373 miles) away. Even in one of the richest regions in the world, this infrastructure, which does not care about borders and distances, is running out of steam. Los Angeles has been suffering from water shortages for two decades, a problem out of step with its residents' standard of living.

Africa is home to 86 of the world's 100 fastest growing cities.

In rich countries, the system is breaking down more quickly than we thought. In Africa, it is an absolute emergency. It is the last continent to urbanize, and the one that is doing so the fastest, without a state structure capable of financing the infrastructure that this implies.

Between high birth rates and rural exodus, Africa is home to 86 of the 100 fastest growing cities in the world. At least 79 of them — including 15 capitals — are facing extreme risks due to climate change.

​Kinshasa's floods to Cairo's "urban hell"

The 13.2 million inhabitants of Kinshasa, the capital of the Democratic Republic of the Congo, are already regular victims of flooding. They will be twice as many by 2035. In Ethiopia, the number of city dwellers will increase from 24 to 74 million in the next three decades. Egypt's urban population will then reach 85 million, compared to 43 million today. It's so much growth that the authorities will have to create a new capital to relieve the urban hell of Cairo.

How to provide housing and equipment, roads and transport, drinking water and sanitation at such a sustained rate? It is impossible. Tensions over access to water, energy and telecommunications will increase as cities continue to have needs that exceed their territorial production capacity. Conflict is inevitable. We are heading for disaster.

That is unless we radically change the way we build our world. In Africa as elsewhere, this means first of all putting an end to the illusion of the city without limits. Some, like Sebha, will have to be abandoned to nature, and thousands of new ones will have to be built. But the thinking must be reversed, to find a balance between populations, resources and territories.

The new city must be appropriately sized, limited by its own resources: if a given territory can provide water and energy for 50,000 people, then the future city must not exceed that size.

Nomads not refugees

To do this, we must reconnect with the visible infrastructure of the past, which was part of the landscape, calling for collective governance. This was the case of the Roman aqueducts and also of the Agdal basins, which integrated urban agriculture, as well as the wells located in each neighborhood, as is still the case today in Venice. This is now being tried in Morocco, with the creation of the city of Mazagan, near El-Jadida, which we already know will not have more than 200,000 inhabitants.

The consequences of climate change, demographic pressure and rampant urbanization leave us no choice: Africa must be the scene of the reinvention of the city in the 21st century. And for that, it is urgent that it becomes again a laboratory of architectural and urban experimentation, with all the more legitimacy that it will no longer be, as in the past, a colonial laboratory.

We must decolonize our thinking.

On the contrary, we must tap into what Africa is capable of offering the world through modes of organization, traditional resource management and the use of materials that have fallen into oblivion. This kind of experimentation is, for example, the raison d'être of the Moroccan Pavilion at the Dubai 2020 World Expo. Made of raw earth, the building stretches 34 meters tall, an unprecedented height. More durable than concrete, raw earth, an African material par excellence, also makes it possible to do without air conditioning in one of the hottest places on earth.

If Africa continues to impose urban planning models thought up elsewhere, without a critical dimension, it will end up in chaos. Here too, we must decolonize our thinking and imagine collective organizations that will enable us to adapt to the major displacements that climate change is already imposing on us. It is in Africa that we can learn to be nomads again, so as not to become refugees.