Those who remember the flash floods that plagued the capital in 2021 will know the damage that such natural disasters can cause.
The Met Office is now warning that similar storm events will be four times more frequent if emissions remain high.
Indeed, the GLA has identified flash floods as the main environmental risk to London.
This comes after a report released in January by the London Climate Resilience Review found that the capital was "underprepared" for climate change.
Surface flooding, which refers to when large amounts of rainfall on hard surfaces like concrete, overwhelming the local drainage system, was described as a "lethal" risk to all.
However, a possible solution originating from China is being put forward, known as ‘sponge cities’.
What are sponge cities?
A sponge city relies on green spaces like parks and wetlands and blue spaces like ponds and rivers to absorb rainwater, reducing the amount of water on hard urban surfaces to mitigate flooding.
It also helps reduce the amount of rainwater that enters sewage systems, something that has been a problem for London in the past.
Sponge cities reduce the need to manually remove water without installing large-scale infrastructure like sewage pipes.
China made sponge cities a priority in 2013 as part of a multibillion-dollar policy across the country. Its success sparked similar initiatives in other cities around the world, such as Dhaka, Kenya, Berlin, and Los Angeles.
Could sponge cities work in London?
The ‘sponginess’ of cities relies on the aforementioned green and blue spaces. London has various parks dotted throughout the capital but also lots of hard, urbanised spaces.
In 2022, British development firm Arup published a report examining London's sponginess using computer modelling. When compared with Auckland, Mumbai, Nairobi, New York, Shanghai, Singapore and Sydney, London was deemed the second-least spongy with a rating of just 22%.
As such, more wetlands and green spaces are needed, as well as sustainable drainage systems (SuDS). These are decided on at a local council level.
While a report following the 2021 London flash floods found gaps in the capital’s preparedness for such an event, the London Climate Resilience Review in 2022 found that London was still unprepared.
With rising temperatures likely resulting in more extreme weather, the worry is that London is not preparing for such eventualities fast enough.
