Mexico City is drinking itself into the ground

Mexico City's cathedral, which had to be propped up with stone wedges as it was being built to stop it sinking. Image: Francisco Diez

When the Aztecs founded the city of Tenochtitlán in the middle of a lake, they thought they were being incredibly clever.

It was 1325, the height of the era of Mesoamerican tribes vying for supremacy in the narrowing strip between the Pacific Ocean and the Caribbean Gulf, and a small island on the western side of Lake Texcoco seemed like a pretty good place to be. 

The Mexica people who lived there – and from whose tribe the name Mexico now comes – became enormously successful. Their Aztec Empire was the most formidable force on the continent, exerted control and influence for thousands of miles around, and established trading relationships stretching as far as the Inca Empire in modern-day Peru.

Their island city, smattered with canals, causeways, and dykes, was a lesson in sustainability.

Lake Texcoco and the city of Tenochtitlán before s*** went down. Image: Yavidaxiu.

The channels they built provided natural irrigation and water management, while floating gardens called chinampas kept the city fed as it grew to an astonishing size. By the time the Spanish conquistadores arrived in the 16th century, the city had approximately 300,000 residents – making it five times the size of London at the time.

The Mexico City of today is a very different story.

A choked-up Mexico City today. Image: Fidel Gonzalez/creative commons.

Up no creek with no canoe

A choking, smog-shrouded sprawl of 21m people. It has no island, no lake, a water shortage that means millions are left with empty taps on a regular basis, and is sinking at an astonishing rate.

Roughly 20 per cent of Mexico City’s residents cannot guarantee that water will come out of their taps every day, and the ground is sinking by as much as nine inches a year in some suburbs. That’s the equivalent of nearly a storey a decade.

The city’s cathedral, which took more than 200 years to build, has a leaning chapel and bell tower, propped up by stone wedges to stop the whole thing crumbling down. The Gilded Angel of Independence – a local tourist hotspot and national landmark – was built with nine shallow steps leading up from the street below. As the surrounding area has sunk, an extra 14 large steps have been added as the angel is increasingly left marooned above a vanishing city.

Slanted buildings leer menacingly over pavements, their doors and windows no longer in alignment with their friends as if crudely displaced from a grotesque theme park funhouse. Terraced streets built on level ground now undulate, with wavy gables crowding up against each other in parts, and pulling away in others, while city-dwellers struggle up hilly pavements where once the path was flat.

In Iztapalapa, a suburb of approximately 2m people built on the ancient lake’s southern shores in the city’s south-east, 15 primary schools have crumbled or caved in, and a teenager was swallowed up when a gaping crack appeared in the street.

So what happened?

As per usual, the blame can be placed squarely on the shoulders of the pesky European invaders.

Xochimilco, the last vestige of Mexico City's lakeside history. Image: Owen Prior.

Veni, vidi, conquistadori

When Hernán Cortes entered the city in 1519, he was “stunned by its beauty and its size”, and in awe of a city where he was welcomed as a god and given plush lodgings by the Aztecs. This, obviously, did not last: war ensued, and the conquistadores took control of the city and named it the capital of their new colony, the Viceroyalty of New Spain.

Where the Aztecs had constructed dykes and channels to live in harmony with the lake, the Spaniards covered them over to build roads and increase the city’s size. They started draining the lake and cutting down the forests on its shores, making the city more susceptible to intense flooding.

Mexico City suffered major floods in 1555, 1580, 1604, and 1607, before one bright spark proposed moving the capital to dry land in 1630. But after deliberating on this for a while, the authorities decided that the answer was no, and the flooding continued, with more serious deluges in 1645, 1674, 1691, 1707, 1714, 1724, 1747, and 1763.

One flood was so severe that the entire city was submerged for five whole years from 1629 – yet the city lived on, gasping for air and expanding further across the lakebed between downpours.

By the 20th century, most of the lake had been drained, and flooding became the least of the city’s worries. As it grew and grew, and poorer migrants from the surrounding country arrived in search of economic opportunity, Mexico City grew thirsty.

Which was a problem.

The Gilded Angel of Independence, which has risen above the sinking streets. Image: TJ DeGroat.

Geologically insane

The city is built on two different geological foundations. Some of the ground underneath Mexico City is volcanic soil, which was fertile and used by the Aztecs for growing crops. It was also handily water-absorbent: moisture would soak in and flow to underground aquifers easily, without damaging the structure of the soil.

But when developers built on the volcanic soil and covered it in concrete and asphalt, water could no longer get through to the soil and filter through to the aquifers on which the city relies. And other parts of the city sit on clay. This, unlike the volcanic soil, can't absorb the water, merely sandwiching it between layers of clay – like cream between layers of pastry. When the cream is sucked out, the layers of pastry crack and collapse, falling on top of one another.


And that’s what’s happened beneath Mexico City. Desperate for water in a lake basin devoid of a lake, the city has tapped into the clay soil while covering over the useful volcanic soil. And as the city is built on a mixture of both geologies, it has sunk in an uneven, mismatched way, causing dangerous fissures, cracks, and the bizarre phenomenon of wavy, undulating streets.

It is estimated that the city has dropped 10 meters in the last century; if anything the signs are that this process is accelerating.

The climate change doom blockbusters show us coastal cities dramatically engulfed by storms and waves from rising sea levels, as great ice shelves melt in the Arctic and Antarctic.

But one of the first cities claimed as victims by man-made destruction may be less cinematic: a leviathan of 21m sinking into the ground, cracking and buckling, swallowing up people, houses, and livelihoods, and starving its poorest residents of water and hope as it goes. 

Jack May is a regular contributor to CityMetric and tweets as @JackO_May.

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The smartphone app placing virtual statues of women on the map

A virtual Edith Wharton in Central Park, New York City. Image: The Whole Story Project.

If you’re a woman, then in order for you to be immortalised in stone, bronze or whatever once you’ve shuffled off this mortal coil, you should either have royal blood or be willing to be sculpted naked. That is the rule of thumb.

A statue that actually celebrates a woman’s achievements is a rare sight. Writing in the New Statesman last year, equality campaigner Caroline Criado-Perez found that out of 925 statues in Britain, as listed by the Public Monuments and Sculpture Association, only 158 are of solo women. Of these, 46 are of royalty, including 29 of Queen Victoria. Fourteen depict the Virgin Mary.

There are signs of change, albeit slow. The suffragist Millicent Fawcett is set to be honoured with a statue in Parliament Square, where currently all 11 of the statues are of men. (They include Nelson Mandela and a nine-foot Gandhi.) The monument is to be unveiled next year to celebrate the centenary of British women receiving the right to vote.

Elsewhere, the late comedian Victoria Wood is being honoured with a statue that’ll be erected in Bury, Greater Manchester. In the Moss Side area of the city, a statue of Emmeline Pankhurst will be unveiled in 2019. Unlike the Fawcett one, neither of these is expected to receive public money, relying on crowdfunding and other sources instead.

So how many more statues of women, regardless of how they’re funded, would we need to build in order to reduce the gender gap? Well, according to Jonathan Jones, art critic at the Guardian, the magic number is: zero.

Jones’s argument, back in March, was that building statues doesn’t advance feminism, but simply traps us in the past. He wrote:

Statues don’t hold public memory. They politely bury it. These well-meaning images melt into the background scenery of our lives.

Whether this is empirically true is questionable, but it’s true that we tend not to erect them as often as we used to anyway. This is partly because there is less space available for such monuments – a noticeable disadvantage cities of the present have compared to those of the past. In order to reduce the imbalance, statues of men would probably have to be removed; many would no doubt be okay with that, but it would mean erasing history.

One partial answer to the problem is augmented reality. It can’t close the gender gap, but it could shine a spotlight on it.

To that end, an advertising agency in New York launched an app at the beginning of May. The Whole Story allows users to place virtual statues of women on a map; other uses can then view and find out more about the individuals depicted at their real-world locations, using their smartphone cameras.


Currently, users have to upload their own virtual statues using 3D-modelling software. But going forward, the project aims for an open collaboration between designers, developers and organisations, which it hopes will lead to more people getting involved.

Contributions submitted so far include a few dozen in New York, several in Washington and one of Jane Austen in Hyde Park. There are others in Italy and the Czech Republic.

Okay, it’s an app created by a marketing firm, but there are legitimate arguments for it. First, the agency’s chief creative office has herself said that it’s important to address the gender imbalance in a visual way in order to inspire current and future generations: you can’t be what you can’t see, as the saying going.

Second, if the physical presence of statues really is diminishing and they don’t hold public memory, as Jones argues, then smartphones could bridge the gap. We live our lives through our devices, capturing, snapping and storing moments, only to forget about them but then return to and share them at a later date. These memories may melt away, but they’ll always be there, backed up to the cloud even. If smartphones can be used to capture and share the message that a gender imbalance exists then that’s arguably a positive thing.  

Third, with the success of Pokemon Go, augmented reality has shown that it can encourage us to explore public spaces and heighten our appreciation for architectural landmarks. It can also prove useful as a tool for learning about historical monuments.

Of course no app will replace statues altogether. But at the very least it could highlight the fact that women’s achievements are more than just sitting on a throne or giving birth to the son of God.

Rich McEachran tweets as @richmceachran.

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