Did the Telegraph deliberately get it wrong about London immigration?
Thames Water asked a team of researchers to estimate the number of people living in the capital. They explain their bafflement when it ended up on the front pages.
Welcome to London Centric, where we’ve sat down with the authors of an internal Thames Water estimate of the capital’s “clandestine” populations to discuss how they accidentally found themselves at the centre of a political firestorm. It’s a tale of lies, damn lies, and statistics — as well as a desire by sections of the media to portray the capital in a permanent state of crisis.
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The mayor’s plan to put money in your pocket.
Sadiq Khan launched a new growth plan for the capital on Thursday morning at Imperial College — setting out ways to boost the capital’s economy and make Londoners richer over the next ten years.
It’s a shopping list of big asks for the city such as investment in education, housebuilding, and new transport projects. But the mayor’s limited powers compared to other global cities means many of the proposals rely on central government handing over either more money or control.
Khan told London Centric he’s also hoping to build projects, such as the Bakerloo line extension in south London and the Docklands Light Railway extension to Thamesmead, by working with developers or borrowing against future tax revenues. He said this is similar to how the Elizabeth line was funded: “We aren’t asking for big cheques, we’re asking for innovation on how we fund them. It’s not necessarily the Exchequer paying for this stuff.”
The mayor said he’d been talking with deputy prime minister Angela Rayner and transport secretary Heidi Alexander. He is optimistic that the Labour government will soon devolve extra powers to the Greater London Authority that go far beyond what is being granted to other English cities: “Our competitors, with respect to Manchester, Yorkshire, and the West Midlands, aren’t those regions. It’s New York, it’s Paris. We’re the most centralised democracy in the Western World.”
Asif Aziz reopens negotiations with the Prince Charles Cinema.
Sadiq Khan spent last night at the switch-on of central London’s Ramadan lights. The wildly popular annual event is funded by the Aziz Foundation, the charitable arm of Asif Aziz’s property empire — the same landlord exposed by London Centric last week for the poor quality of his housing and for trying to “bully” the Prince Charles Cinema off its site,.
The cinema has now said that, following a public outcry and reporting in outlets such as London Centric, it is “feeling more positive” and Aziz’s company has reopened negotiations on a new lease for the venue.
Asked about Aziz, Khan told London Centric: “I saw him last night and wished him Happy Ramadan. The Ramadan lights aren’t paid for by taxpayers. They’re paid for by the Aziz Foundation, who do a huge amount of philanthropy, and also London Business Alliance. I don’t think we should conflate the Ramadan lights with some of the issues you’re raising, I simply don’t know the issues you’ve raised. What I do know is the Ramadan lights are a huge boon not just for Muslims or Londoners but across the globe in these difficult times of uncertainty and instability and an increase in hatred.”
The London driver with buyer’s remorse.
Elon Musk’s closeness to President Donald Trump is causing issues for some owners of Teslas in London’s more liberal areas. This electric car driver was spotted by London Centric driving through the capital with an apologetic “Anti Elon Tesla Club” bumper sticker attached to their car, amid reports that sales of the electric vehicle brand are collapsing in the UK.
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“There's a whole series of things that have been misrepresented”: What happens when your research on London’s population hits the front pages.
Richard Culf never intended his company’s estimates of London’s population to be read by anyone outside of a handful of staff at Thames Water.
Edge Analytics, his statistics consultancy based on the University of Leeds’ campus, had been hired by the water company to research London’s “hidden and transient” residents, sometimes called the “clandestine” population. Their findings would meet Thames Water’s regulatory requirement to estimate how many humans are using the company’s water on a typical day, while informing future infrastructure demands such as whether the company needs to invest in extra reservoirs.
“We’re basically trying to report on populations that don’t appear in official published statistics,” said Culf, explaining this included people who are living illegally in the the capital but also Ukrainian refugees, second home owners, and tourists staying overnight in London’s hotels. His company’s conclusions were submitted in February 2023 and the team moved on to other work.
As a result Culf was shocked to wake up last month and find the Daily Telegraph had obtained the internal document through data transparency laws and put it on its front page under the headline: “One in 12 in London is illegal migrant.”
His company was suddenly in the middle of a very modern media storm. At one end was a water company trying to plan for future infrastructure demand by estimating how many human bodies are drinking, washing, and excreting in the capital. And at the other end was a growing political conviction, driven by elements of the right-wing media, that the exact scale of London’s illegal immigrant population is known by the authorities but is being kept hidden from the general public.
Other news outlets, ranging from the Times to the Daily Mail, swiftly reprinted the Daily Telegraph’s story in full. GB News went to town on it, while debates were also held on other broadcasters. The Home Office insisted the report’s research was “deeply flawed”, while London Standard columnist Melanie McDonagh also insisted the report’s figure was wrong — because, she argued with little evidence, the proportion of illegal residents in the capital must be even higher. Edge’s website was swamped with visitors, while MPs phoned up asking to see the secret figures.
A month later, Culf, the managing director of Edge Analytics, spoke with London Centric for his first proper interview on how a piece of work never intended for public consumption accidentally created a media firestorm — and how British newspapers treat the tricky, nuanced and messy topic of illegal immigration levels in London.
“There's a whole series of things that have been misrepresented,” he said of the original Telegraph piece, which is already the subject of multiple corrections and complaints to the press regulator Ipso.
Culf listed his concerns: First, his company’s report acknowledged its own uncertainty by offering a low, medium, and high estimate of the broader “irregular” population — but Telegraph’s front page headline presented the highest estimate as a definitive fact about “illegal migrants”.
Secondly, the Telegraph marginally exaggerated the proportion of illegal immigrants due to a basic maths failure that meant the outlet used “the wrong denominator” for the capital’s official population.
Finally, the newspaper conflated the ‘London’ being talked about in Edge’s internal report with the larger geographic and political entity of Greater London. The ‘London’ used in Edge’s analysis is the name used by Thames Water for a specific ‘water resource zone’ that stretches deep outside the capital’s boundaries into Kent and Hertfordshire while excluding Harrow, Dagenham, and Sutton.
“It's an interesting subject,” said Culf. “But the way that it's being reported is kind of missing the point really.”
He said his company was just focussed on estimating the number of humans using water in the capital and it was wrong to reverse-engineer the figures to find other outcomes: “We're not saying anything about legality, we're not saying anything in particular about migration as a separate thing. We're not trying to make any comment about their legal status.”
Official estimates for the number of permanent residents in the capital are relatively easy to come by, putting Greater London’s population at just under 9m people. But there are no official estimates on the transient and hidden population, which includes illegal immigrants or people staying in London temporarily. This matters if you’re trying to build a water supply system that can take the strain.
“In London you’ve got a population that changes a lot on a daily and weekly basis,” said Culf. “And many of the people in that area aren't captured as being normally resident in the statistics.”
Edge’s February 2023 report estimated that there were between 390,000 and 585,000 “irregular migrants” in the “London water resource zone” which contains around 7m people.
Jonathan Portes, professor of economics and public policy at King’s College, is critical of the Daily Telegraph for taking “the upper bound of a very uncertain estimate” and using that as its attention-grabbing headline. But he also criticised the data sources used by Edge to build its estimates, especially some “lazy” work done by research agency Pew in 2017 which counted foreign citizens with legal leave to remain in the UK as part of the irregular population.
“My instinct is the numbers from these top down studies are over done,” Portes told London Centric, arguing that the real number of illegal migrants in the capital could be far lower than many people believe. He citied previous immigration spot checks on benefits claimants and criminal arrests, which found far fewer illegal residents than had been expected: “The only way to find out would be to cordon off a large part of London and check everyone’s papers. But we’re never going to do this, even in the name of social science.”
One of the most frustrating things for politicians and businesses is that all researchers are ultimately just making educated guesses when it comes to the level of illegal migration in London. Mihnea Cuibus, of the University of Oxford’s Migration Observatory, said his work involved a constant battle against “the desire for certainty” in the hope journalists and politicians will learn to live with nuance: “The public and the media want a number and the reality is we don’t know. Our role is to make them understand how much uncertainty there is here. It’s a very unsatisfying answer, I’ll give you that.”
Cuibus said that the rush to take political stances in debates about immigration “makes us forget about our inability to know” and he often had conversations with people in the government who struggle to deal with the lack of hard facts. Instead, he is pinning his hopes on a new effort by the Office for National Statistics to estimate illegal migration level using different data sources such as police encounters and NHS health data: “If we end up seeing that, that’s going to be very interesting and exciting because it would be based on some kind of hard data.”
No one doubts that there are a substantial number of illegal residents in London, with the typical individual more likely to be a student who has overstayed their visa rather than someone who crossed the English Channel on a small boat. If Cuibus had to guess, he would suggest the number of illegal immigrants in the capital is at the bottom end of Edge’s estimates, or around 1 in 20 of the population — still equivalent to hundreds of thousands of people.
A lot of the media coverage of the Thames Water report has also been shaped by an audience who live outside the capital but lap up depictions of London as a lawless overpopulated hellhole. The Telegraph journalist who broke the story normally writes anti-immigration comment pieces. Edge has done similar work on population estimates for water companies across the UK but, according to Culf, the topic is “more difficult and more controversial” in London than in the rest of the UK.
Culf insisted his company’s report was never intended to be used in this manner: “We’re not trying to pretend this is a definitive count of people down to the last decimal point. What we are saying is these hidden populations exist and, in planning for the provision of services and resources, they need to be accounted for.”
The Times and Mail have already issued corrections to their stories on the report, while Portes wants the Telegraph to run a front page correction over errors in its original piece.
Portes also has a theory for why this particular report estimating London’s illegal population was so appealing to newspapers: “The fact that it was a secret report by Thames Water, with implication that somehow they were measuring the volume of our pee, is what makes it work.”
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"I don’t think we should conflate the Ramadan lights with some of the issues you’re raising, I simply don’t know the issues you’ve raised. "
What? The Mayor denies any knowledge of a major story on his patch? Does his office not even subscribe?
You can chastise the Telegraph for getting its numbers wrong, but Portes saying it’s “my instinct” the numbers are wrong doesn’t do much for the prosecution case.