Responding resiliently to the effects of climate change (water bombs included) goes through a key rule: making nature our ally and learning from its intelligence

At the COP27 international meeting Simon Kofe, foreign minister of the Oceanian island nation Tuvalu, speaking to world leaders from the metaverse.

It is there that the island will have to migrate to ensure its survival, at least culturally, given the progressive rise of the waters which will lead to its cancellation from the earth's surface.

Provocation or reality? The drastic effects of global warming confront us with the urgency of rethinking our ways of consuming, producing, moving, feeding and living.

Is Italy at risk of flooding?

It might appear that this is not an issue that concerns Italy, yet Legambiente, in the annual report of the Città Clima Observatory, disseminates unequivocal data: from 2010 to September 2022, 510 floods were recorded in the Peninsula with serious damage to people and infrastructure.

"There is no more time to lose", declared Stefano Ciafani, national president of Legambiente. "It is necessary to update and approve by the end of the year the national plan for adaptation to the climate crisis, on standby since 2018, to implement serious territorial policies for the prevention of hydrogeological risk, with a national law against soil consumption and relocation interventions.

How do you live with the water emergency?

Meanwhile, many countries have long since found ways to coexist with water. What unites them? They rethought their design policies by understanding and indulging in nature, welcoming water flows and facilitating absorption and conservation for dry periods.

Nature is based on circularity - for those looking for inspiration, read the an interview with architect Pietro Laureano, a scholar of oases and deserts - where every element, from the ground to the air, competes in the search for balance.

When does water become dangerous?

Water becomes an enemy rather than a resource:

  • when the irrepressible drive to build and cement leads to waterproofing of the ground surface
  • when building without following river flows
  • when the land is left uncultivated leading to its slow desertification and therefore less capacity to retain water.

What if cities were instead redesigned in synergy with nature? What if, using biomimicry, instead of fighting the waters we were able to welcome" them?

What are Sponge Cities?

The Sponge Cities (in Italian sponge city) are places that adopt systems diversified and interconnected to absorb large quantities of water strong> and release them slowly.

How do they work? They use different urban design strategies, located throughout the territory: starting from the planting of green roofs and sidewalks bordered by vegetation, to the creation of collection points for rainwater and the improvement of river and soil drainage, decementing it.

READ ALSO: From cities to sponge landscapes: projects from around the world

What is water design: how to design by studying local water cycles

It is the so-called urban planning approach based on water design, which is based on a strategic use of local water cycles: for example, the international giant Arup which has a specialized department on this type of design.

Analyzing through Artificial Intelligence 8 cities - Auckland, London, Mumbai, Nairobi, New York, Shanghai, Singapore and Sydney - Arup measured their capacity to absorb water, evaluating the types of soil, how much percentage covered by 'grey infrastructure' such as concrete, sidewalks and buildings and as much as 'blue and green infrastructure' including grass, trees, ponds and lakes.

Auckland, New Zealand leads the way with 35% green area largely due to its stormwater systems, many golf courses, green parks and good sized residential gardens. In last place is London, at 22%, mainly due to high levels of concrete and poor soil absorbency.

"Cities cannot continue to be concrete jungles," explains Mark Fletcher of Arup. "To thrive, they must work in harmony with nature. They need to quickly learn how to implement nature-based solutions that can bring much broader benefits than traditional gray infrastructure engineering and contribute positively to biodiversity and carbon reduction."