It is sometimes hard to tell where Carlos Slim stops and Mexico City starts. He controls most of the mobile phone, landline and internet markets. His telecoms company, Telmex, installed the city’s surveillance cameras. Grupo Carso, his flagship infrastructure conglomerate, runs the city’s principal water treatment plant. His bank, Inbursa, is Mexico’s sixth largest. He even owns the city’s only aquarium.

In 2015 Slim’s companies accounted for 6% of the entire country’s GDP, according to the Mexican media outlet El Universal. These holdings run parallel to a vast network of strategically located retail properties. But more than anywhere or anyone else, the 77-year-old tycoon and sometime world’s richest man has grown with the capital. Like a ghost in a shell, Carlos Slim has become part of Mexico City’s urban fabric.

Now, in the autumn of his career, the Valley of Mexico – Slim’s canvas – is running out of space. Grey concrete has raced up the ravines and invaded the wooded slopes of the Sierra Madre mountains surrounding the city and stretched out to the Lake of Zumpango to the north.

The only large open area remaining lies to the east, amid the swampland of Texcoco – almost all that is left of the once-great lake system that filled the basin.

This is where the man known as el Ingeniero, the engineer, will make what is likely to be his last great urban intervention: a massive new airport, expected to be the third-largest in the world.



“This is the only area where there is still room for such a large project,” says Gabriela Bojajil of DAFdf Arquitectura y Urbanismo, one of the architectural bureaus that participated in the bid for the Ciudad Aeroportuario, a planned mixed-use development by the terminals. “It is like a hole in the city.”



The stakes are high, and not just for Slim. Should this project be a success, it will be his crowning glory, a symbol of his role in shaping Mexican modernity and a great gateway for the country’s global ambitions. Should it be a fiasco, future generations will see it as an ostentatious monument in an era long on mathematics and short on wisdom, in which natural resources existed to be consumed, megaprojects were a way to keep the poor fed and occupied, and the future was an afterthought.



The planned international airport, which would be the third-largest in the world. Photograph: Foster + Partners

The site of Mexico City’s new airport is covered in red volcanic gravel. It is also the last space in the Valley of Mexico open to large-scale urbanisation. The city’s eastern quadrant is a big, flat, empty spot on the map, within striking distance of its central districts.



The airport, expected to be completed in 2020, was first proposed in 2001 by the State of Mexico government under Arturo Montiel, the uncle of current Mexican president Enrique Peña Nieto. Fierce resistance by the communities who would be displaced by the airport led to its cancellation the next year. But according to Mexican trade magazine Obras, quiet preliminary work on a revived airport project took place between 2011 and 2014, through the state-owned company Aeropuertos y Servicios Auxiliares.

In October 2014, Peña Nieto announced the airport project in his State of the Union address. He declared it would be a solution to the saturation of Mexico City’s current Benito Juarez airport. The concession went to the majority state-owned company Grupo Aeroportuario de la Ciudad de México; Slim’s conglomerate, Grupo Carso, is in charge of the consortium building the £3.9bn terminal, as well as one of the runways. A day later, Reuters reported that a multidisciplinary jury had awarded the airport’s design to Norman Foster, the Pritzker prize-winning English architectural superstar, and to Fernando Romero, who also happens to be Slim’s son-in-law.

The airport is a hugely complicated project: approximately 4,430 ha in its first stage, with three runways, a mixed-use service area called Ciudad Aeropuerto, an industrial park and a capacity of 50 million passengers a year – 50% more than the current airport.

Construction at the new international airport in the Valley of Mexico. Photograph: Bloomberg/Getty Images

As well as Foster, foreign participants include the English systems company Arup (who created the masterplan), the Boston Consulting Group (who designed the business plan), the Spanish construction companies Acciona and FCC (who are helping build the terminals), and the Netherlands Airport Consultancy (who is in charge of the design of the runways, terminal building, taxiways, platforms and support buildings). Parsons International is the project manager.

In December 2015, the Auditoria Superior de la Federación, Mexico’s federal government office, warned of lack of transparency in the design, construction and operation of the airport.

Critics have also noted that the instability of the waterlogged lakebed of Texcoco, which makes building a megaproject of this scale, in an earthquake zone, highly complex. What’s more, the new site reproduces one of the main flaws of the current site: it is extremely close to the built-up area of the city so neighbourhoods nearby are affected by noise and other pollution.

None of that is likely to stop it being the last big Mexico City venture of Slim’s long career as a developer. He envisages it as the capstone of a vast network of urban holdings and projects going back more than a century to Mexico City’s hardscrabble Merced neighbourhood. Slim’s own father, Julián, arrived in the Merced at the turn of the 19th century from the village of Jezzine in Lebanon, to join four of his older brothers who had emigrated a few years before. Julián Slim Haddad owned a shop called La Estrella del Oriente amid the neighbourhood’s bustling textile markets.

“For many Lebanese migrants, buying property meant putting down roots,” says Ubaldo Helu, a baker who lives in the area and is a distant relative of Slim. The Lebanese community here remembers the business exploits of the Slim family well.

The new international airport is a $13.4bn project. Photograph: Foster + Partners

“Julian Slim became a big property owner in this neighbourhood during the Mexican Revolution,” says Helu. “He bought the properties of people who were fleeing the city at bargain prices. At one time he owned up to 100 buildings here.”

Mexico City has changed from a city of industry to a city of commerce and services during Slim’s lifetime Victor La Chica

Carlos Slim, a former stockbroker, now owns the mall next to the Valley of Mexico’s oldest pyramids in Cuicuilco. He owns Mexico City’s first skyscraper. He was the main driver behind the remodelling of Mexico City’s historic centre, where he owned 78 buildings as of 2015, according to Mexican daily Excelsior. Grupo Carso built Latin America’s largest water treatment plant, and his Plaza Carso houses two of the city’s most iconic new museums, the Museo Soumaya and the Colleción Jumex. He built the first mall in Ciudad Nezahualcoyotl, the legendary shantytown now consolidated into one of the megacity’s most populous districts.

Slim’s projects tend to demonstrate an eye for the missing piece in the urban plan, and a sensibility for intangible values, such as history and identity. Whereas most other developers in Mexico City specialise in either housing, retail, office or industrial space, Slim’s Grupo Carso distinguishes itself by the diversity of projects.

“Mexico City has changed from a city of industry to a city of commerce and services during Slim’s lifetime,” says Victor La Chica, CEO of real estate services company Cushman & Wakefield Mexico. “This means that demand has increased for retail and office space. Slim has managed successfully to profit from this structural change.”

In housing, La Chica notes that increasingly well-educated young people will strike out to live by themselves instead of living with their parents until they marry, creating demand for lofts and starter apartments. Slim’s renovation of the historic centre and mixed-use buildings in the Plaza Carso fit this new pattern. Gene Towle, CEO of real estate consultant Softec, estimates that the city will need to create 4.5 million new homes by 2050. He suspects these homes will be built in along the northeastern rim of Mexico City, with or without an airport.

Reforma Avenue in Mexico City. Slim was the main driver of the city’s redevelopment. Photograph: Bloomberg/Getty Images

“One thing that surprised me while I interviewed him is that Slim’s street-level knowledge of Mexico City is comprehensive,” says journalist Enrique Osorno, whose biography Slim: Portrait of the World’s Richest Man will be published in English by Verso Books towards the end of 2017. “Carlos Slim has said his urban vision is to see the city as built up of small cities each one complete in its way.”

Yet Slim’s property empire has not been constructed without controversy. His projects have met public opposition as far back as 1997 when he converted a derelict factory next to the Valley of Mexico’s second oldest pyramids into a mall. Critics says the finishings of the Museo Soumaya and Plaza Carso are second rate, and that the project has created serious infrastructure problems for the area around it. Slim’s most recent setback was the Corredor Chapultepec, a linear park inspired on New York’s High Line, running through some of Mexico City’s most rapidly gentrifying neighbourhoods. Public outcry led to a referendum in which the project was voted down in 2015.

Slim’s penchant for building in declining areas has led to a paradoxical situation where public interest in these previously neglected places only arises after he has announced a project.

Carlos Slim is worth $64bn, according to Forbes

In some ways, the airport project in the basin of Texcoco is similar. Built on a desiccated area interlaced with garbage dumps, it has remained largely outside of the public eye until now. Yet this project is far more ambitious and consequential than any other in his portfolio. The Valley of Mexico incredibly still houses 2% of the world’s biodiversity, according to researchers at the Universidad Autonoma de México Xochimilco – to build on its few remaining lake areas is a fraught issue.

Another concern is that Peña Nieto’s presidency has been plagued with corruption scandals. The mere fact that the head of one company of the consortium building the airport, Grupo Hermes, is a son of Carlos Hank González, a prominent State of Mexico governor in the 70s who famously quipped “a poor politician is a poor politician”, raises the shadow of a doubt over the probity of the use of public funds in this $13.4bn project.

Slim is in many ways the perfect example of the cosy links between business and politics in Mexico. At crucial junctures, the state has stepped in to help Slim – such as when he acquired a hard to come by stock brokers’ license as a young man, or the privatisation of the state-held telephone monopoly Telmex in the 1990s, or the many government bids he has won over the years.

The selection of his son-in-law to help build the terminal building is equally typical; at Romero’s wedding to Carlos Slim’s youngest daughter, Dutch architect Rem Koolhaas of OMA Studio (where Romero kicked off his architectural career) was the groom’s witness. The 46-year-old graduate of Mexico City’s Universidad Iberoamericana – whose grandfather Raul Romero Erazo was one of the principal sub-dividers of the slum lands of Ciudad Nezahualcoyotl in the 50s – has become the architect of choice for his father-in-law’s projects.

In the 1980s, Julian Slim Helu, Carlos’ elder brother, rose to become director of Mexico’s equivalent of the FBI, demonstrating that at least one member of the Slim family had political connections. Now Slim will pass on his empire intact to the next generation of sons, sons-in-law and nephews. This proudly rapacious cadre of corporate princes – led by figures such as son-in-law and Mexican Shark Tank panellist Arturo Elias Ayub – will then hold the reins to the city and the sprawling business empire beyond it. It will be more difficult to pass on the political acumen and connections that have made Carlos Slim a consummate man of the system.

Indeed, it is a testament to Slim’s power that it’s hard to imagine that an airport would be built without him – and as long as he is involved, the project has an air of inevitability.

Although Mexico will hold presidential elections in 2018, and opposition hopeful Andrés Manuel López Obrador has said he would cancel the airport project, in February the secretary for communications and transport said 85% of the total contracts for the construction of the airport will be assigned by the end of 2017, making cancellation next to impossible. As of May, 15% of the construction work had already been done, according to Mexico’s El Economista newspaper.

How well the airport project is conducted remains to be seen, but what is in very little doubt is that the willow lanes of rural Texcoco will disappear, a tide of concrete will sweep over the lakebed, and in the last act of Carlos Slim, the Valley of Mexico will at last be fully urbanised.

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