![](\"https:\/\/varosieso.hu\/wp-content\/uploads\/2024\/06\/Yu-150x150.png\" "\\"Yu\\"")
<\/span><\/div><\/div><\/div>Kongjian Yu pioneered the concept of China’s “sponge city” – less concrete and more green space, harnessing rainwater instead of fighting it. The good example is being followed by many metropolises around the world.<\/b><\/p>\n<\/div> Yu was recently awarded the Oberlander Prize of the Cultural Landscape Foundation for his work on sponge cities.<\/span><\/p>\n<\/div><\/div><\/div><\/div><\/div> The classic method of treating stormwater by draining it out of the city as quickly as possible through sewers has failed. As the atmosphere gets warmer, it can hold more and more rainfall, leading to increasingly violent storms, and torrential downpours overwhelm the creaking infrastructure that should be carrying the water away. Our cities were designed and built for a climate 100, 200, 300 years ago, but that climate no longer exists.<\/span><\/p>\n The new strategy of urban planning and development in China is to slow everything down. Since 2013, China has had a national strategy to transform its growing metropolises into sponge cities that retain rainwater rather than getting rid of it quickly. If engineers can slow down the run-off and allow it to seep into the ground – rain gardens, <\/span>Spreading ground (Spreading ground)<\/span>, permeable pavements and urban wetlands, these options can both reduce the impact of flash floods and recharge deeper aquifers. And this will become increasingly important as the planet warms and droughts intensify: sponge cities are designed to collect water on rainy days to provide a reserve for drought days.<\/span><\/p>\n<\/div><\/div><\/div><\/div><\/div> “When it rains, we retain as much rainfall as possible,” says Kongjian Yu, the concept’s developer and founder of the Beijing-based design firm Turenscape. “We slow down the run-off and let the soil absorb it. The sponge city becomes an adaptable city, a porous landscape with flexible water management.”<\/p>\n<\/div><\/div><\/div> According to a recent study, US cities could soak up billions of litres of water a day if they followed China’s lead and accelerated sponge projects. <\/span><\/p>\n “The sponge city is an immediate solution that can make cities adapt to climate change, heat, floods and drought,” says Yu.<\/span><\/p>\n One of the things that makes this concept so powerful is that it can be implemented at different scales. In Los Angeles, for example, there are open areas hundreds of metres in diameter where water can seep into the aquifer, but thin strips of roadside can also be sponged by creating green spaces.<\/span><\/p>\n Water is precious. If we can retain rainfall in our gardens, we don’t have to water trees and plants because the water stays put – the treasure is right here, under our feet. And this approach works at personal, individual and community level.<\/span><\/p>\n Industrial engineering has simply messed up the whole water system on a global scale. Groundwater is declining everywhere, and this is finally causing huge problems – bigger problems than the devastation of flash floods.<\/span><\/p>\n The problem needs to be solved holistically, and the sponge city is a nature-based, holistic solution that is cheap and can be implemented on a small scale. On a regional, larger scale, we need a bigger, more complex plan to see where we can make more room for water. This more complex plan has holistic benefits: by filling reservoirs, the environment will be more beautiful, which will increase property values, but also support biodiversity.<\/p>\n When there is vegetation, temperatures drop dramatically immediately, which can save lives in a city. This can be done with a green roof, a green wall, or any green surface – you can have green everywhere, and this not only reduces reflection, but also reduces temperature due to evaporation (transpiration and evaporation).<\/p>\n<\/div><\/div><\/div><\/div><\/div> Water conservation also has measurable benefits for urban gardens. If urban gardens can produce more food locally, this can reduce transport emissions. Aquaculture can be used to grow any crop that can be combined with water management. This approach creates not only a new way of looking at things, but also a new aesthetic. We can look at our parks in a different way, making them “wilder” and more productive, bringing back nature, birds and pollinators.<\/p>\n<\/div><\/div><\/div><\/div><\/div> In China, the development of sponge cities has gone hand in hand with urban growth. The question may arise as to how an existing metropolitan infrastructure can be transformed into a water-retaining infrastructure. But Yu says it’s just a question of attitude. Even Central Park can be turned into a sponge park. Los Angeles is a flat city with lots of irrigated gardens – these gardens simply need to be turned into sponges.<\/span><\/p>\n For a long time, the civilised solution was to drain the water as quickly as possible. Both rainwater and waste water. On one side, we pump out our waste water, so the city will be clean and hygienic. On the other side, we’ll bring water into the city and create a beautiful irrigated lawn. This is what we call civilisation. But this is a completely wrong and unsustainable idea.<\/p>\n Traditional stormwater management, what we call grey infrastructure – concrete, pipes and pumps designed to drain water as quickly as possible – has failed or will fail because of climate change. If we rebuild this infrastructure, we will only make things worse or fail again.<\/p>\n But if you go for the green alternative, you not only save money, but the impact is more immediate. The sponge city essentially uses the free services of nature. It’s that simple.<\/p>\n But the problem is precisely that it is free. No one wants to invest because no one can make money from it. Therefore, the business model, policies and philosophy need to change.<\/p>\n<\/div><\/div><\/div><\/div><\/div>Is your city prepared for the effects of climate change? <\/span><\/h4>\n
![](\"https:\/\/varosieso.hu\/wp-content\/uploads\/2024\/06\/kina1-1.jpeg\" "\\"k\u00edna1\\"")
<\/span><\/div><\/div><\/div><\/div><\/div>What about the other big urban problem, heat?<\/h4>\n
![](\"https:\/\/varosieso.hu\/wp-content\/uploads\/2024\/06\/kina2.jpeg\" "\\"k\u00edna2\\"")
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