Besides being a heavily polluted city, Beijing is sinking. Studies made by a Spanish engineer, Roberto Tomas of the University of Alicante, and Chinese academics, Chen Mi of the Capital Normal University in China and Li Zhenhong of Newcastle University in UK, of the movements under the capital city found that in some parts, the soil was sinking at 8 to 11 centimeters a year.
The study used satellite radar technology by comparing images of the city’s landscape between 2003 and 2011, reported RT.com. They found that the worse affected area was in the city center, in Chaoyang District, while in heavily populated residential communities, there was ongoing gradual displacement.
The researcher explained the sinking to overuse of groundwater. They added that since 1935, Beijing has been suffering from land subsidence. To avert the negative impact that could result from the situation, the group is assessing the potential threat to roads, buildings and critical infrastructure such as high-speed railways.
Because Beijing rests on a dry plain which had accumulated groundwater over the past thousand years, the wells eventually were drilled, causing the water table to drop and the underlying soil to compact. The situation is similar to a sponge that was dried out, reported The Guardian.
It is estimated that there are thousands of water wells throughout Beijing used for landscaping and farming. Ma Jun, a leading environmentalist in China and director of the Institute of Public and Environmental Affairs in Beijing, noted that the state has some regulations and oversight power over the installation of wells, but its application is inconsistent and enforcement dubious.
Beijing uses about 3.5 billion cubic meters of water annually. To source additional water resources for China’s growing population, the government has a $62-billion water diversion projects that would bring in 44 billion cubic waters per year from the Yangtze River to north China where urbanization is moving at a fast pace.