Shanghai Metro is building a 174-kilometer underground railway and says that 2 million square meters of underground space will be used for the Metro system, including stations and a business complex.
Liu Chunjie, the Metro's chief engineer, revealed the development at the 5th China (Shanghai) underground space development conference yesterday. It wasn't announced where the line would run.
He said the number of people using the Metro daily is now 10.65 million. "It took us 10 years to raise the daily figure from 100,000 people to 1 million," Liu recalled, adding that numbers are increasing rapidly.
As a result, underground space is becoming more important for Shanghai as above-ground resources are increasingly in short supply.
"The 13th-five-year plan period is vital for Shanghai's transformation of land use pattern and land resources reform," said Deng Jianping, deputy director of Shanghai Housing and Urban Development Commission. "The plan explicitly encourages cities to jointly develop both above ground and underground space."
Dr Jia Jian from Tongji University said that up to 2016, more than 60 million square meters of underground space had been utilized.
According to the Regulation on Shanghai Underground Space Planning and Construction, released in 2014, underground space is divided into three layers — superficial, mid level and deep.
"Now developers have come to realize the economic value of underground space, even the deep layer," said Qian Shaohua, vice-president of Shanghai Urban Planning and Design Research Institute.
Qian added that Shanghai will build into a further 100-kilometer-long underground space for infrastructure and pipe galleries within the next five years.