Facing rising flood threat, municipality's proposals for storing rainwater runoff both environmental and practical

Chongqing's first demonstration "sponge" garden was recently opened to the public in the city's Yubei district, marking an additional step toward its embrace of the "sponge city" concept.

The garden, which is part of Chongqing Central Park, covers an area of about 700 square meters and is equipped with sustainable water systems that can collect and purify rainwater runoff from approximately 2,000 square meters of impermeable ground in a nearby plaza, according to the Chongqing Municipal Department of Housing and Urban-Rural Development.

The garden also supports sustainability, and is planted with decorative, long-living plants. Water stored in the overflow ports from multiple gardens can be redirected to sustain the plants through a network of pipelines and sprinklers.

Flooding is one of the most serious water-related issues facing many Chinese cities, and is a consequence of rapid urbanization, changes to land use and the disappearance of natural wetlands. To cope, China turned to the concept of creating "sponge cities" on a mass scale seven years ago.