Chinese architect and urbanist Kongjian Yu, celebrated worldwide as the pioneer of the “sponge city” concept, has reportedly died in a plane crash in Brazil’s Pantanal wetlands. He was 62 years old.

Yu’s work has been transformative in confronting climate change. Rejecting the 20th-century reliance on concrete, pipes and drains to force storm water away, he championed “green infrastructure” – restoring wetlands, reshaping roads, creating parks and reservoirs – so that urban environments could absorb and recycle water like a sponge. His approach, once considered radical, is now enshrined in Chinese national policy and increasingly adopted abroad.

When Monocle Radio spoke with Yu in September 2024, he traced his ideas back to his childhood in rural China. Born in 1963, he grew up in a village regularly hit by monsoon floods. “I don’t remember the water being so dangerous compared to today,” he said. “The river was fully covered with vegetation – willows, reeds, all kinds of plants. Now rivers are channelised, concreted. Floods are far more dangerous.”

This experience shaped his belief that we must work with nature, not against it. “About 65 per cent of Chinese cities suffer flooding every year,” said Yu. “Concrete and pipes never succeed. To retain water, slow the flow and recycle it in the dry season, you have to make a city like a sponge.”

His persistence eventually shifted policy at the highest level. He published his first formal proposals in 2003; a decade later, China’s president, Xi Jinping, and the National People’s Congress officially embraced the model. By 2015, 60 metropolises were designated as pilots for the programme. “All of these places are now required to build with the sponge-city model in mind,” he said, calling it a “systematic transformation”.

During our interview, Yu was eager to show how the idea had spread beyond China. He pointed to Bangkok’s Benjakitti Forest Park, a former tobacco factory site that was transformed into a landscape capable of holding a million cubic metres of storm water. He also mentioned projects in Pakistan, Mexico and Brazil, where officials were exploring similar approaches to flood resilience. “But we need more than just sponge cities – we need a sponge planet,” he said.

Yu’s influence stretched across architecture, urbanism and public policy, and his projects blended ecological pragmatism with civic imagination. As the world wrestles with extreme weather, his vision feels ever more urgent. A year on from our conversation, revisiting his words is a reminder of both his prescience and his optimism.

Listen to the full interview on The Urbanist on Monocle Radio.