A new study analyzing land subsidence across 465 cities in 107 countries reveals that while the sinking of urban land remains a widespread global challenge, the phenomenon has generally slowed in recent years. The findings, published October 12 in the journal Nature Cities, provide a systematic assessment of ground deformation between 2014 and 2023.
Nature Cities land subsidence assessment
Mexico City records most intense localized subsidence
Researchers from Peking University, South China Normal University, and other institutions identified significant disparities in how cities are sinking. Subsidence is most severe in regions across Southeast Asia, West-Central Asia, and North America.
Mexico City recorded the most intense localized subsidence, with some areas sinking at a rate of approximately 217mm—or more than 0.2 meters—per year. Other cities experiencing high median sinking rates include Medan, Indonesia, at roughly 33mm per year, Bandung, Indonesia, at 22mm per year, and Mashhad, Iran, at 16.5mm per year. In China, approximately 16% of the land area across 82 major cities is sinking at a velocity exceeding 10mm annually. Meanwhile, coastal cities in the United States, including New York, Boston, and San Francisco, are sinking at rates between 2mm and 6mm per year.
Groundwater extraction drives soil compression
The causes of this ground compression are diverse, ranging from tectonic shifts, earthquakes, and natural soil consolidation to human activities like building and mining. However, groundwater extraction remains a primary driver of the phenomenon. As urban populations grow and freshwater supplies face increased strain, the resulting depletion of underground aquifers causes the soil to compress, leading to surface sinking.
South-to-North Water Diversion Project management
Despite these severe hotspots, the study detected a marked deceleration in subsidence across many cities in Southeast and East Asia. Researchers attribute this downward trend in sinking rates to effective water resource allocation and improved groundwater management strategies.
Hu Xie, a researcher at Peking University, noted that large-scale infrastructure and policy efforts have yielded measurable results. In China’s Beijing-Tianjin-Hebei urban agglomeration, for example, the South-to-North Water Diversion Project and stricter groundwater management have successfully replenished water levels in certain areas, significantly easing subsidence.
Open platform for global urban land subsidence
Land subsidence poses a persistent threat to urban infrastructure, damaging buildings, foundations, and sewage systems. In coastal areas, the combination of sinking land and rising sea levels driven by climate change increases the vulnerability of communities to severe, long-lasting flooding.
To assist policymakers in identifying risks and prioritizing intervention, the research team has launched an open platform for global urban land subsidence. This tool offers the study’s dataset in a visual and searchable format. Tao Shengli, a researcher at Peking University, stated that as big data regarding geology and groundwater accumulates, and as artificial intelligence and modeling techniques advance, the ability to assess subsidence risks will continue to improve. The study authors emphasize that this research provides a consistent baseline for future monitoring, which remains essential to determine if these trends of slowing subsidence will persist.