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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Budget 2017: Philip Hammond just showed that rejecting metro mayors was a terrible, terrible error

Sorry, Leeds, nothing here for you: Philip Hammond and his big red box. Image: Getty.

There were some in England’s cities, one sensed, who breathed a sigh of relief when George Osborne left the Treasury. Not only was he the architect of austerity, a policy which had seen council budgets slashed as never before: he’d also refused to countenance any serious devolution to city regions that refused to have a mayor, an innovation that several remained dead-set against.

So his political demise after the Brexit referendum was seen, in some quarters, as A Good Thing for devolution. The new regime, it was hoped, would be amenable to a variety of governance structures more sensitive to particular local needs.

Well, that theory just went out of the window. In his Budget statement today, in between producing some of the worst growth forecasts that anyone can remember and failing to solve the housing crisis, chancellor Philip Hammond outlined some of the things he was planning for Britain’s cities.

And, intentionally or otherwise, he made it very clear that it was those areas which had accepted Osborne’s terms which were going to win out. 

The big new announcement was a £1.7bn “Transforming Cities Fund”, which will

“target projects which drive productivity by improving connectivity, reducing congestion and utilising new mobility services and technology”.

To translate this into English, this is cash for better public transport.

And half of this money will go straight to the six city regions which last May elected their first metro mayor elections. The money is being allocated on a per capita basis which, in descending order of generosity, means:

  • £250m to West Midlands
  • £243 to Greater Manchester
  • £134 to Liverpool City Region
  • £80m to West of England
  • £74m to Cambridgeshire &d Peterborough
  • £59m to Tees Valley

That’s £840m accounted for. The rest will be available to other cities – but the difference is, they’ll have to bid for it.

So the Tees Valley, which accepted Osborne’s terms, will automatically get a chunk of cash to improve their transport system. Leeds, which didn’t, still has to go begging.

One city which doesn’t have to go begging is Newcastle. Hammond promised to replace the 40 year old trains on the Tyne & Wear metro at a cost of £337m. In what may or may not be a coincidence, he also confirmed a new devolution deal with the “North of Tyne” region (Newcastle, North Tyne, Northumberland). This is a faintly ridiculous geography for such a deal, since it excludes Sunderland and, worse, Gateshead, which is, to most intents and purposes, simply the southern bit of Newcastle. But it’s a start, and will bring £600m more investment to the region. A new mayor will be elected in 2018.

Hammond’s speech contained other goodies for cites too, of course. Here’s a quick rundown:

  • £123m for the regeneration of the Redcar Steelworks site: that looks like a sop to Ben Houchen, the Tory who unexpectedly won the Tees Valley mayoral election last May;
  • A second devolution deal for the West Midlands: tat includes more money for skills and housing (though the sums are dwarfed by the aforementioned transport money);
  • A new local industrial strategy for Greater Manchester, as well as exploring “options for the future beyond the Fund, including land value capture”;
  • £300m for rail improvements tied into HS2, which “will enable faster services between Liverpool and Manchester, Sheffeld, Leeds and York, as well as to Leicester and other places in the East Midlands and London”.

Hammond also made a few promises to cities beyond England: opening negotiations for a Belfast City Deal, and pointing to progress on city deals in Dundee and Stirling.


A city that doesn’t get any big promises out of this budget is – atypically – London. Hammond promised to “continue to work with TfL on the funding and financing of Crossrail 2”, but that’s a long way from promising to pay for it. He did mention plans to pilot 100 per cent business rate retention in the capital next year, however – which, given the value of property in London, is potentially quite a big deal.

So at least that’s something. And London, as has often been noted, has done very well for itself in most budgets down the year.

Many of the other big regional cities haven’t. Yet Leeds, Sheffield, Nottingham and Derby were all notable for their absence, both from Hammond’s speech and from the Treasury documents accompanying it.

And not one of them has a devolution deal or a metro mayor.

(If you came here looking for my thoughts on the housing element of the budget speech, then you can find them over at the New Statesman. Short version: oh, god.)

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and also has a Facebook page now for some reason.

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