“Sponge Cities”: A new survival strategy for major urban areas! Harnessing nature to reduce floods, capture rainwater, and combat the climate crisis

Cities around the world are turning to the concept of the “Sponge City” to tackle flash floods and extreme rainfall. The idea is to transform urban areas so they can absorb, store, filter, and release water—just like a natural sponge.

China began developing this model in 2014 and has since expanded it to multiple cities, including Shenzhen, Xiamen, and Chongqing, using green infrastructure such as permeable pavements, rain-absorbing parks, green roofs, and stormwater wetlands.

Experts say Sponge Cities can help reduce flooding, increase green spaces, ease urban heat, and make effective use of rainwater. However, challenges remain—particularly in funding, long-term maintenance, and the fact that many cities have yet to adopt the approach citywide.

Urban planners around the world increasingly view Sponge Cities as a key solution for the future, helping cities cope with heavier rainfall, extreme weather, and more frequent flooding.