海绵城市(hǎimián chéngshì): Sponge cities

Premier Li Keqiang called for the construction of more sponge cities to solve urban flooding in the Government Work Report he delivered to the nation's top legislature on March 5 during its annual session.

It is the first time that sponge cities have been included in the central government's work report.

A sponge city is an environment-friendly concept in city planning that attaches great significance to the underground pipe network design and construction so that rainwater can be collected and recycled for multiple uses. Urban flooding has occurred in 180 cities in China each year on average from 2014 to 2016.

Although the central authority proposed to build sponge cities in 2015 and set an ambitious goal of 80 percent of China's urban area being a "sponge" by 2030－the overall investment is estimated at 1.6 trillion yuan ($232 billion) and progress has been bitterly slow, with only 30 cities earmarked and supported by the central government as pilot cities to try the idea in practice.

But the report says the government will construct underground pipe networks of more than 2,000 kilometers this year and initiate a three-year plan to prevent flooding and eradicate waterlogging in urban areas.

Analysts said writing the sponge city into the Government Work Report means the central authorities will set aside more funds to support this endeavor and encourage investors to help fund the upgrading and expansion of underground pipe networks.

Huge amounts of investment are required. If carried out nationwide, sponge cities will become a robust engine for growth and promote the development of relevant industries.