Mexico City, which now sits on top of Tenochtitlan, is sinking fast. It was first built by the Aztecs in the 14th century, who chose a good strategic location on an island in the middle of a lake, because that was easier to defend.
The aquifers that supply the city’s groundwater are being depleted much faster than they can be refilled.
Mexico City and the surrounding urban area of more than 20 million people consume up to 287 billion gallons of water a year, 70 percent of which is drawn from its subterranean aquifers.
There is no balance anymore.
The situation causes the ground to sink and buildings in the city are leaning slightly.
When the city’s population started to grow, artificial islands were built and connected with the help of paths known as causeways.
When the Spanish conquered the Aztecs in the 16th century, they decided to drain the lake altogether.
The water table is sinking at a rate of 1 meter (3.2 feet) per year. The problem is growing and only getting worse because the city’s population grows and water demand increases.