In recent days, the world of landscaping and urbanism said goodbye to one of the most influential voices in ecological planning: the Chinese landscape architect Kongjian Yu. His departure reinforces the importance of revisiting his work and reflecting on how his ideas continue to shape the future of cities. Yu was a pioneer in the integration of nature and urban infrastructure, and the concept of sponge cities, widely associated with his name, has become a landmark in discussions about urban resilience. The absence of Kongjian Yu leaves a gap, but his work remains a guide and a call to action. His research, which challenges the idea that the city should fight water, offers an alternative and urgent vision for 21st-century urbanism. In Brazil, where water and urban challenges are intense, his legacy inspires the development of cities that absorb — and do not merely resist — water. Below, learn more about the history and trajectory of this architect who transformed the way urbanism is thought about in China and became a global reference. Who was Kongjian Yu? Kongjian Yu was born on May 12, 1963, in Dongyu Village, Jinhua County, Zhejiang Province, China. He witnessed rural life up close and grew up amidst nature, an experience that would shape his vision of the harmonious relationship between water, landscape, and human habitation. He obtained his Bachelor's and Master's degrees in Landscape Architecture at Beijing Forestry University. Later, he went to the United States and completed a Doctor of Design (DDes) at the Graduate School of Design at Harvard University, with a thesis focused on "ecological security patterns in landscape planning." During his time at Harvard, Kongjian Yu was influenced by thinkers like Ian McHarg, Carl Steinitz, and Richard Forman, references in ecological urbanism and the integration of nature and urban design. In 1998, he founded the firm Turenscape, based in Beijing, specializing in landscaping, urban planning, ecological restoration, and green infrastructure. Under his leadership, the firm grew and operates in hundreds of cities, with projects that combine ecology, aesthetics, and functionality. Kongjian Yu was a professor at Peking University and also published dozens of books and hundreds of academic articles, advocating the idea that cities should not "fight against" nature — especially water — but learn to coexist with it. This contemplative philosophy led him to coin and promote the concept of sponge cities, which would be adopted as national policy in China. In recognition of his work, he received important awards, including the Cornelia Hahn Oberlander International Landscape Architecture Prize in 2023. Resilient cities and the role of sponge cities What is urban resilience? Before understanding sponge cities, it is essential to talk about urban resilience. This concept refers to the ability of cities to absorb shocks, such as floods, droughts, or extreme weather events, to adapt to new conditions and recover without compromising the well-being of their inhabitants. For Kongjian Yu, resilience does not just mean resisting adversity but coexisting with nature, taking advantage of natural cycles to improve urban quality of life. Instead of "fighting against water," his proposal was to integrate it into the daily life of cities, transforming it into an ally in creating safer, healthier, and more sustainable environments. The concept of sponge city The concept of "sponge city" proposes that the city functions as a natural sponge: absorbing, retaining, filtering, and slowly releasing rainwater instead of merely draining it away. Instead of "expelling" water with sewer systems and pipes, the sponge city coexists with water, storing it in vegetation, permeable soils, basins, wetlands, and releasing it in a controlled manner. In other words, the paradigm shifts from "combating floods" to "coexisting with water." In an interview with Archpaper, Kongjian Yu succinctly summarizes this philosophy: "The philosophy of living with water is the complete opposite of living against water... a sponge city retains water on site instead of draining it." Sponge cities combine green infrastructure (such as rain gardens, permeable pavements, restored streams, floodable parks, constructed wetlands) with technical infrastructure (pipes, reservoirs), in an integrated manner centered on the natural water cycle. The concept not only helps mitigate flooding but also offers additional benefits like aquifer recharge, pollutant filtration, increased urban biodiversity, reduced heat islands, aesthetic improvements, and recreational spaces that are functionally integrated into the water system. Adoption in China and practical challenges Since the mid-2010s, China has officially adopted the sponge city concept as part of its national policy aimed at urban planning and stormwater management. In 2015, 16 pilot cities were selected to test sponge city interventions, and in subsequent decades, the number of involved cities grew to dozens (or more) regions. However, its implementation presents significant challenges: Regional hydro-physical differences: standardized solutions adopted in various regions may not work well under distinct geographic conditions. Mentality conflict with "gray" infrastructure: many projects still favor pipes, rigid drainage, and conventional works. Costs and maintenance: maintaining green infrastructures requires constant planning, cleaning, monitoring, and adaptation. Monitoring and evaluation: performance data is often scarce or inconsistent, making it difficult to measure the real impact. Even so, many Chinese projects have shown promising results in smaller floods, rain retention, and environmental improvement. Notable examples and emblematic projects Qunli Rainwater Park This park, designed by Turenscape, is often cited as a classic model of sponge city in action. It combines retention basins, native vegetation, infiltration channels, and public spaces, functioning as a "green sponge" to capture and store rainwater. Sanya (Hainan) In the coastal city of Sanya, mangrove restoration projects and wetland parks have been integrated into the sponge city concept to mitigate floods and restore coastal ecosystems. Benjakitti Forest – Bangkok, Thailand Outside of China, one example illustrating the international application of the concept: the Benjakitti Forest Park in Bangkok was designed with water storage capacity (about 187,000 cubic meters) to face extreme rainfall events — the park behaves like a sponge within the urban fabric. His relevance and the legacy left The death of Kongjian Yu in Brazilian soil, on a mission linked to his commitment to disseminate the sponge city concept, impacts not only the Chinese landscape but the global panorama of resilient urban planning. His legacy can be understood on several levels: Integration between nature and technique — He broke the dichotomy between "green infrastructure" and "grey infrastructure," proposing a synthesis where both coexist harmoniously. Decentralization of hydraulic control — Instead of centralized and rigid works, he advocated that each plot (neighborhood, block, park) could capture, retain, and release water locally. Versatility (multi-benefit) — The interventions promote more than flood control: biodiversity, leisure, urban beauty, microclimate, and quality of life. Scalability and adaptability — His proposal can be applied at various scales (from a single lot to an entire basin), provided there is sensitivity to the location. Global inspiration — Many architects and urban planners have looked to the sponge city model as inspiration to face urban climate challenges worldwide. The relevance of Kongjian Yu lies in the fact that he not only proposed a "technical method" but a coherent urban philosophy: a city that truly coexists with its water ecology. His death in a country where his concept can have real practical application may inspire a new generation of more resilient cities in Brazil.
