The sinking of Mexico City has reached the point that the historic center is at a lower level than the deepest part of Lake Texcoco, according to a hydraulic engineer who participated in a seminar on Mexico City’s water supply.
“Lake Texcoco was the lowest point in the Valley of México, and now the zócalo is below the level of the lake,” said Fernando González Villarreal, a researcher at the Engineering Institute of the National Autonomous University.
González said the sinking, which has been a constant since the mid-19th century, is caused by the exploitation of the aquifers under Mexico City. The aquifers are replenished with water at an average rate of 25 cubic meters per second, about half the rate at which water is extracted from them.
“The problem is that the sinking isn’t even, and in some places there are different levels of sinking,” he said. “That means broken pipes, buildings leaning to the side, and it makes repairs and maintenance very expensive.”
In some areas, the city is sinking as much as 40 centimeters a year — up to as much as 10 meters over the course of the last century.
González thinks that some kind of drastic action — likely costing as much as 20 billion pesos (US $1 billion) a year for the next 15 years — needs to be taken to address the issue. Such action could include finding alternative sources of water, artificially replenishing aquifers or rebuilding the city’s waterworks, parts of which are as much as 100 years old.
“It’s in very bad shape, and we need to do a lot of work to reduce all the leaks,“ he said. “We also need, in my opinion, to recharge the aquifers artificially.”
Mayor Claudia Sheinbaum said her administration takes the water problem seriously, and that more resources are being directed towards improving hydraulic infrastructure.
“An issue as important as the issue of water, we shouldn’t see it as a conflict, but rather as an opportunity for collaboration,” she said. “And this is a message of collaboration: we may have differences on some issues, but here, we are in a community, working together to help Mexico City move forward.”