Bengaluru should aim to be Kongjian Yu’s sponge city
The city should use this urban planner’s ideas to achieve harmony with natural water cycles
is co-founder of Siana Capital, a venture fund manager.
India’s information technology (IT) capital, Bengaluru, a city once lauded for its greenery, grapples with the formidable challenge of both urban flooding and water scarcity. The paradox of a city inundated yet thirsty is stark. Its water ordeal is a tale of many years of ecological neglect and urban mismanagement. Rampant urbanization and increased coverage of the city’s surface with asphalt and concrete have obliterated natural water absorption and drainage pathways, exacerbating monsoon floods and leading to severe water scarcity in dry seasons. Groundwater levels have plummeted and the city’s reliance on distant water sources is unsustainable and precarious.
Laments abound on social media about how the city has trampled its founder Kempegowda’s original plan of a network of lakes and inter-linked canals that kept the city flood-free during the rains and sufficiently watered during its hot, dry seasons. But it is difficult to blame any single person or group. All the residents of Bengaluru are culpable.
The unravelling of Kempegowda’s vision and drying out of its many lakes and tanks has gone on for decades. For instance, Miller’s Tank, which existed in my childhood, was ‘bunded’ and dried out even before I finished school. The lake-bed housed a slum for many years before giving way to a hospital, offices, auditoriums and housing long before Bengaluru was even on the IT map.
An answer to the city’s crisis may lie in the visionary concepts of Kongjian Yu, a Chinese urban planner and landscape architect renowned for his ‘sponge city’ initiative. Yu, a recent winner of the Oberlander Prize for architecture (bit.ly/49XHZdm), has been credited with rejuvenating China’s overgrown cities and his ideas are being proposed for other urban dystopias like New York City and Los Angeles. I am no urban planner, but it seems that Bengaluru, the city of lakes that seemingly forgot how to manage its water, could solve its water woes by transforming into a sponge city.
At its core, the concept is ingeniously simple. The basic idea is for cities to absorb, clean and use rainwater efficiently and sustainably. Imagine a Bengaluru where, instead of concrete jungles that repel water, urban landscapes mimic sponges, soaking up rainwater to reduce flooding, replenish groundwater and even purify water for reuse. Yu’s methods use green roofs, permeable pavements, wetlands, rain gardens and enhanced green spaces. The philosophy underpinning his concepts is not just about managing water, but harmonizing urban development with nature’s cycles.
In a recent interview with Wired, Yu says, “A sponge city can be on any scale. Water is precious. If you retain water in your backyard, you don’t have to water your trees, you don’t have to water your garden, because water is underneath—your treasure is here. It’s at a personal, individual, community scale.” (bit.ly/4973EPm).
To be fair, the city’s water authority did try several times to make its residents install ‘rainwater recharge systems’ in their homes. When I installed such a system in my house many years ago, I remember asking a neighbour why he hadn’t done so. He mumbled something about not being given enough incentives to do it. His home has now been pulled down and is giving way to a massive, ugly concrete block of apartments that will likely house a hundred people where six once lived.
Bengaluru can use Yu’s methods to increase its permeable surfaces, step up groundwater recharging and provide natural flood defences. Lakes and tanks in Bengaluru should be restored to the extent possible and reintegrated with a managed network to act as storage reservoirs. By cleaning, desilting and reconnecting these water bodies, we can restore their role in the city’s water management strategy.
More practically, adopting permeable pavements in public spaces, creating wetlands and rain gardens in urban areas and installing green roofs on buildings can significantly increase the city’s capacity to absorb and utilize rainwater. These measures can also reduce the burden on drainage systems and mitigate flooding.
Turning Bengaluru into a sponge city would require a collaborative effort by the government, private sector and the community. Incentives for green infrastructure development, public awareness campaigns on water conservation and community-led projects could spearhead this transformation. A recent advertisement in a newspaper had the local water authorities asking firms to use their corporate social responsibility (CSR) monies to help, harkening back to a column I wrote in this space asking Bengaluru’s IT firms to belly up to the bar to help restore the city. (bit.ly/3Pq62tl)
The path to becoming a sponge city is challenging. Land use planning needs to be revisited, with a focus on sustainable development that prioritizes water management. Financial investment is crucial, as is the political will to undertake such a transformation. However, the benefits—reduced flooding, enhanced water security, improved urban biodiversity and a better quality of life—make for a compelling case.
“The sponge city is basically using free nature,” Yu says in his interview. “It’s simple. The problem is that it’s free. No one wants to invest in it, because no one can make money.” Yet, the vision of a city in harmony rather than battle with water is both inspiring and essential. Use of CSR money might be the watershed moment it needs.