NASA-ISRO satellite reveals Mexico City sinking fast as water crisis worsens

A joint satellite mission by NASA and the Indian Space Research Organisation (ISRO) has mapped alarming rates of ground sinking across Mexico City, revealing that parts of the capital are subsiding by as much as 50 centimetres every year. The data, released this week, underscores the deepening water crisis in one of the world's most populous cities.

Mexico City, built on the dried bed of Lake Texcoco, has long struggled with land subsidence. But the new measurements from the NASA-ISRO Synthetic Aperture Radar (NISAR) satellite provide unprecedented detail on how quickly the ground is giving way. Some neighbourhoods are dropping at rates that threaten infrastructure and daily life.

Satellite data paints a stark picture

The NISAR satellite, launched in 2024, uses advanced radar to measure ground deformation with millimetre-level accuracy. Its latest survey shows that large swathes of Mexico City are sinking unevenly, with the highest rates recorded in the eastern and central districts. In some areas, the ground has dropped by over half a metre in a single year.

Scientists say the primary cause is the relentless extraction of groundwater from the aquifer beneath the city. As water is pumped out to meet the needs of nearly 22 million residents, the clay-rich soil compacts and sinks. The process is irreversible in the short term.

Water crisis fuels the problem

The sinking is inextricably linked to Mexico City's water crisis. The city's ageing water supply system loses an estimated 40% of its water due to leaks. In many areas, piped water reaches homes only a few hours a day, forcing residents to rely on private wells or trucked-in water. This has accelerated groundwater pumping, further destabilising the ground.

Officials have not yet confirmed the full extent of the damage, but early studies suggest that the uneven subsidence is causing cracks in buildings, roads, and underground pipelines. The city's metro system and drainage networks are also at risk.

Global implications for water management

The Mexico City findings are a stark warning for other cities around the world that rely heavily on groundwater. Similar subsidence has been reported in Jakarta, Venice, and parts of the Indian subcontinent. The NISAR satellite, a collaboration between NASA and ISRO, is now being used to monitor these regions as well.

Experts point out that India's own urban centres, particularly in the Indo-Gangetic plain, face similar risks. Cities like Delhi and Kolkata are extracting groundwater at rates that could lead to subsidence if left unchecked. The satellite data could help planners identify vulnerable zones before damage becomes severe.

The mission's ability to provide high-resolution, frequent updates makes it a powerful tool for tracking environmental change. With climate change putting additional stress on water resources, such monitoring is becoming critical.

What comes next

Mexican authorities are now studying the NISAR data to prioritise areas for water conservation and infrastructure reinforcement. The satellite will continue to monitor the city's subsidence over the coming months, offering a clearer picture of how the crisis evolves. For now, the message is clear: the ground beneath Mexico City is shifting, and the clock is ticking on finding a sustainable water solution.