Our World

Why is Mexico City sinking?

Today in Geo we discussed how Mexico City continues to sink eachyear, so I decided to do some research and here’s what I found:

The world's second most populous city is sinking at a rate of about three inches per year. Many cities have experienced this as well. For example, Venice, has sunk about 9 inches during the 20th century. But from here Venice's problems seem minimal. As a matter of fact, during the last century, Mexico City has sank about 30 feet!

But the most severe damage is taking place underground, where the subsiding soil is rupturing sewer lines, water pipes, and subway tunnels. As if these problems aren't serious enough, Mexico City sits on a major fault line, and the loss of ground water and collapsing soil have made the city more susceptible to earthquake damage.

So why is Mexico City sinking? Well, it's because the ancient aquifers that supply 72 percent of the city's ground water are being emptied faster than they can be refilled, and that is causing the ground to sink. Part of the reason the water is disappearing so quickly is that every year, 350,000 new people move to Mexico City, which is already bursting at the seams with 24 million residents.

Can anything be done to solve Mexico City's water problem? The water difficulties have become a degenerate circle: as the city expands, more water is pumped from the aquifer. As more is drawn out, the city submerges further. The sinkage bursts more underground water pipes, sending fresh water gushing into the sewers, disturbing the shortage, demanding more water to be pumped from the aquifer, and so on. The most evident solution is to stop pumping water from the aquifers. However, there are too many people and not enough other water sources for the city to stop using the aquifers completely. To help solve the water problem, the government has asked citizens to conserve and re-use water. But since the people of Mexico City are used to getting all the water they need from the city's old supply, this has proved to be easier said then done. If you were a city official, what would you do to solve the crisis?

Mexico City is sinking

posted by Anonymous @ 2/27/2006 08:42:00 PM