The climate crisis has accentuated changes in the amount of rainfall, causing droughts or storms with large volumes of water, which result in floods that can cause great damage to urban infrastructure. To combat this, the sponge city is a solution that has a green infrastructure to operate the infiltration, absorption, storage and even purification of these surface waters.
But what exactly is a sponge city? They are cities designed so that rainwater is kept and absorbed where it falls through sustainable urban drainage systems, leased from its green infrastructure. In other words, it is prepared to reduce the damage from flooding, inundation and inundation.
Green infrastructure technologies involve elements that allow greater permeability in the soil for rainwater absorption. Among them we can highlight: parks, drainage pavements, rain gardens, infiltration and retention wells, urban gardens and plantations, green walls and roofs. You can learn more about each of them here. In addition, all these elements can be combined with the road system and buildings built in the city - which, in this case, comply with a collective social agenda - to assist in the natural flow of water in case it is not completely retained.
It is worth remembering that investing in this green infrastructure is not simple. From a multidisciplinary team that integrates different municipal bodies and areas of knowledge, it is necessary to create a database and detailed analysis with information on the watershed, soil studies, rainfall, insolation, winds, to design interventions in search of better use. Therefore, it is a long-term plan, but it results in many benefits. After all, in addition to reducing the risk of flooding and inundation, the quality of the water is worked on, making it cleaner and enabling its reuse. Besides, other important points can be mentioned, such as improving the microclimate and enhancing urban land, since the increase in green areas directly combats heat islands, increases biodiversity, brings leisure to the population and, depending on the amount, helps in groundwater quality.