A sponge city, simply put, is a city that absorbs rainwater through a series of green infrastructural projects rather than an impermeable system across which rainwater runs into storm drains. It promotes natural measures that allow the water system of the city to operate more naturally. This concept made its way into the limelight after China launched a programme in 2014, starting with the goal of adapting 16 cities across the country, before a further 14 were added in 2016. Since then, this idea has spread around the world and Berlin has become of the latest places to embark upon transitioning into a sponge city. The main issues that a sponge city aims to eradicate include an urban flooding, the degradation of urban ecosystems and, most importantly for Berlin, the urban heat island effect. Berlin, like many other European cities, has been experiencing more and more heatwaves and rainstorms in recent years due to worsening climate change. A plan was therefore created to plant green infrastructure across the rooftops of the city and prevent storm drain buildup by increasing the permeability of pavements.