Sponge City

Urban Design for Absorbing and Reusing Rainwater

China / international

Highlight

Uses green roofs, wetlands and permeable surfaces to make cities absorb, store and reuse stormwater like a sponge.

Extended description

The sponge-city approach redesigns urban areas to absorb, store, filter and reuse rainwater through nature-based and permeable infrastructure rather than rapidly draining it away. Measures include green roofs, rain gardens, wetlands, permeable pavements and restored waterways. Developed at large scale in China and increasingly adopted elsewhere, it reduces urban flooding, replenishes groundwater, improves water quality and creates cooler, greener public spaces.