In 2016, in the city of Quzhou (population 2.5 million), Yu took a deserted, mismanaged 32-hectare landscape and filled it with seasonal crops such as canola, sunflowers, buckwheat chrysanthemums, cosmos and poppies. Out came the site's concrete embankments and in went bioswales that allowed water levels to fluctuate naturally. By creating elevated boardwalks and flood-friendly pavilions, Yu lured the locals. The site, ringed by high-rises, has become a popular ornamental park and productive farmland.

It is a similar story with Yu's work on a deserted 1950s shipyard with wildly fluctuating water levels in Zhongshan (population more than 3 million). Yu reused industrial buildings, created terraces and introduced beds of native weeds to create an open green space where intermittent flooding is welcomed.

Water-sensitive design is happening in lots of countries, Australia included, but Yu told an audience at the National Gallery of Victoria's Melbourne Design Week that the scale of water-related problems in China has called for a particularly ambitious response. With a monsoon climate, China has short periods of concentrated rainfall, followed by months of dry weather. On July 21, 2012, a flash flood in Beijing killed 79 people and forced the evacuation of almost 57,000 people. A year earlier, severe storms in Beijing closed public transport.

While engineers designed thicker drainage pipes and installed stronger pumps, Yu says the scale of the problem calls for a different approach. He proposes something that is "simple, inexpensive and beautiful".

Through his company Turenscape, which has been involved with more than 1000 projects in 200 Chinese cities, Yu designs landscapes that he calls "sponge cities" – like a cloth, they retain and clean water. He keeps artificial infrastructure to a minimum, instead introducing ponds and channels through which water moves by gravity. He plants seasonal crops that suit available water levels or chooses plants that can cope with both wet and dry soils.

He says there is nothing new in any of this. "China has a long history of agriculture and 2000 years ago farmers had a pond system to fight against floods. We have a 2000-year history of building terraces that catch water in the rainy season and keep it through the dry season But we forget this.

"Over the last 40 years, China has urbanised quickly and our cities have been cut off from nature. Industrial technology has been used to drain away storm water and put it into the ocean. But the next month the cities are dry. There's an overall shortage of water in China and the water we have is heavily polluted."

Yu's work specifically addresses the Chinese landscape, bringing back wetlands planted with rice and reintroducing ponds teeming with lotus, water chestnut and fish. But he says addressing environmental problems with productive landscapes and simple technologies has wide application.

"This is not tiny urban gentrification. It is about how messy ecologies and productive, rural landscapes can be urbanised. It's fantastic for how you can solve environmental problems and at the same time produce beauty. For hundreds of years people have distinguished productive landscapes from ornamental ones but now they can come together."