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An international study led by Beijing-based researchers has discovered that the city is dropping by as much as 11 centimeters (4 inches) in some districts per year.
The thirsty city has depleted its groundwater, which the study identified as the cause of the sinking.
Using satellite imagery and GPS data, the team analyzed topographical trends from 2003 to 2010 and found that the city, which has a population of over 20 million, was sinking at an alarming rate.
Its central districts are among the worst affected, the study says. The main subsidence bowls are distributed over the Chaoyang, Changping, Shunyi and Tongzhou districts. Chaoyang, in the eastern suburbs, is the worst affected, with subsidence of 11 cm per year.
Beijing is ranked as the fifth most water-stressed city in the world, the study notes, and as China continues to urbanize, the stress on subterranean aquifers is only set to worsen.
As the water, which has accumulated over thousands of years, is extracted in increasingly greater volumes, the now-dried up soil compacts. The rapid sinking could affect buildings and public works projects, including the city's rail network.
Massive infrastructure projects to divert water, particularly in the north of China, have been undertaken to relieve shortages in some of the country's most stricken regions.
The study was published this month and supported by the National Natural Science Foundation of China.