According to the planning and construction administration of Guian New Area, Guian has invested a total of over 4 billion yuan ($582 million) to promote sponge city projects.

A sponge city is a new way of dealing with urban stormwater. The idea is to transform traditional drainpipes in Guian to create independent clusters of microcirculation to prevent waterlogging.

Guian New Area has implemented over 40 management and control systems to innovate new construction methods, and adapts the PPP model (Public-Private-Partnership) to provide financial support to sponge city projects, said Zhou Xinyang, an officer of the Guian planning and construction administration.

The sponge city demonstration zone in Guian New Area covers an area of 19.1 square kilometers and connects Tianhetan avenue, Hukun high-speed railway, Dongzong road and Machang Technology City.

It contains 75 projects and can deal with a rainfall of 27.3 millimeters. Over 80 percent?of annual rainfall can be drained in the demonstration zone.

Currently, 23 sponge city projects (covering a total area of 6.62 sq km) have been completed, while 52 projects (12.93 sq km) are still under construction.