Mexico City has recently received considerable attention due to its worrying behaviour that cannot be explained by usual urban factors. According to recent observations carried out using satellites, some areas of Mexico City have started sinking at an alarming rate. Although there is no catastrophic subsidence process taking place in Mexico City, the phenomenon is becoming more acute and noticeable in some specific regions. There is no doubt that the process is associated with the existing water problem, which is affecting millions of people in Mexico City.The subsidence process in Mexico City does not lead to catastrophic consequences at once. Nevertheless, the city has started changing gradually and irreversibly. Satellite images provide a better understanding of how the city’s surface moves. However, they also indicate how complex the interaction between water and geological processes has become in Mexico City.Scientists claim that addressing the problem effectively requires implementing new water management policies and developing sustainable urban development plans. If nothing changes soon, Mexico City will experience additional subsidence.
How an old lake is still affecting Mexico City today
Mexico City was initially built on the basin of an old lake; hence, this accounts for most of its present-day vulnerabilities. The soil in this area is composed of very loose and compactable layers of clay that make it vulnerable whenever there are changes in the pressure. With time, the area becomes prone to groundwater withdrawal due to this inherent characteristic.This is because water is removed from the underground aquifer layer, resulting in vacant spaces that tend to cave in, thereby creating sinking of the surface ground. This does not affect the entire area but only certain neighbourhoods. It is suggested that this causes added stress on buildings and structures.
NASA radar shows Mexico City sinking in fine detail
Advanced satellite technology has made it possible to observe these changes with surprising precision. Radar instruments used in Earth-monitoring missions can detect ground movement down to millimetre levels. This allows scientists to track how the city is shifting over time rather than relying only on surface damage reports.Recent data reportedly shows that some parts of Mexico City may be sinking at rates close to 0.8 inches per month. That may not sound dramatic in the short term, but over a year, it adds up significantly. The changes are often invisible day to day, yet they accumulate in ways that can affect entire neighbourhoods.Experts say this kind of monitoring is important because it reveals patterns that would otherwise go unnoticed until damage becomes severe.
Why Mexico City’s water system is under pressure from below
At the centre of the issue is the city’s dependence on groundwater. A large portion of Mexico City’s drinking water comes from an ancient aquifer system located beneath the surface. For decades, this resource has been heavily used to support the city’s growing population.However, continuous extraction has created an imbalance underground. As water is removed faster than it can naturally be replenished, the supporting structure of the soil weakens. This leads to compaction, which causes the land above to sink.
Cracks, tilts, and the visible effects of sinking ground
The effects of subsidence are becoming increasingly apparent in daily life, where roads in some places are no longer even, and there are fissures appearing in the ground. Some structures have become slightly tilted due to subsidence, as they respond to the shifting ground.There is also pressure on the infrastructure, with underground pipelines and transportation and drainage systems having to continually adjust to accommodate ground level changes. In some instances, maintenance may be required much more often compared to other large cities.One of the areas that is being carefully watched for any signs of change is the Benito Juárez International Airport. As airport runways have to be perfectly leveled, even minor changes in the ground can cause issues.
How Mexico City’s water demand is deepening the problem
This issue is directly related to the water deficit in Mexico City. The city hosts over 20 million inhabitants and the water need is very high. With the continuing depletion of groundwater resources, fears grow over the sustainability of water availability.There have been warnings of what is known as “Day Zero”. This involves reaching the critical point of a water deficit, meaning that water would stop coming through the taps for certain portions of the inhabitants. Although it does not seem to be an imminent danger, it is often referred to as an outcome of current trends.As it is connected to the water consumption problem, it becomes more complicated. Groundwater removal causes land subsidence while the latter makes water distribution harder.
