The use of urban underground spaces will be expanded to ease the pressure on land, according to a recent regulation.

By 2020, at least half of China’s cities should complete the planning and approval process for developing underground spaces, according to a regulation released by the Ministry of Housing and Urban-Rural Development on June 28, meaning at least 160 cities will develop and enhance them.

A drive will also be launched to collect the necessary information to facilitate a management system to govern urban underground spaces, which will be incorporated into the nation’s real estate registration mechanism that took effect in March last year.

Underground spaces can be used for a variety of purposes, said Zhang Ruilong, director of the center for underground spaces at the China Institute of Building Standards Design and Research.

These include military defense, easing traffic congestion, transportation, shopping malls and parking lots, and this will help address environmental issues. “In the future, the development of big cities will depend on the utilization of urban underground space,” he said.

The pressure to further utilize areas beneath the surface is growing amid the unprecedented urbanization process that attracts millions of people from rural areas to cities, especially first-tier cities such as Beijing and Shanghai.

In August 2013, Guangzhou, capital of South China’s Guangdong province, became the country’s first city to sell underground space to developers. Two months later, Beijing sold space under the Beijing International Sculpture Park for 322 million yuan ($48.2 million), the capital’s first such move.

In addition, rapidly expanding subway systems also highlight the importance of underground space utilization. At 559 km, Beijing boasts the world’s longest subway network and the country puts more than 300 km of subway lines into operation each year, according to Wang Dongming, deputy director of the Institute of Comprehensive Transportation of the National Development and Reform Commission.

In May, Premier Li Keqiang stressed the importance of underground pipe networks to raise the quality of urban development during a visit to a 6 km-long duct tunnel in Wuhan, capital of Central China’s Hubei province.

Qian Xiaobin, chief engineer for the tunnel, said it contains cables for electricity and internet signals, water supply facilities and bus stations. “The underground tunnel replaces similar facilities that are built on the surface that are vulnerable to floods hitting the city.”

Premier Li said private investment should be attracted to build underground pipe networks which can be upgraded without disrupting overhead traffic.

“We have rising numbers of skyscrapers, but still lag behind developed countries in making use of underground spaces. The spaces should be utilized to create a new Wuhan,” the Premier said.

Tokyo, with its densely packed urban and business areas, has used underground facilities for its districts and wards as have other developed countries such as the United States and the UK.

Zhang said China needs a national management system for underground spaces because developing them is far more complex than building apartments.

Zhang’s opinion was echoed by She Lian, a researcher of underground spaces at the Chinese Academy of Governance. An emergency management system should also be established to curb the risks of developing underground spaces and ensure safety, he said, pointing out that most cities lack a detailed knowledge of the potential of underground spaces and a scientific and comprehensive approach is required to utilize them.