Dave Hill: What is the ULEZ row about and what’s at stake?

Dave Hill: What is the ULEZ row about and what’s at stake?

Sadiq Khan’s plan to further enlarge London’s Ultra-Low Emission Zone (ULEZ) so that it covers the whole of Greater London is the subject of conspicuous continuing arguments – all the more so as the next mayoral election will take place on 2 May 2024, just one year from now.

The Mayor intends to implement the expansion from 29 August, arguing that it will significantly reduce air pollution in the outer London boroughs, bringing public health benefits to all in the city as well as helping to combat climate change and reduce congestion.

The initiative has come under sustained attack by London Conservatives and their media and motorist lobby allies. It is also being opposed in its current form by London Liberal Democrats, and some Labour politicians have expressed concerns. Mayor Khan, however, appears undaunted.

The Background

The current ULEZ covers the 236 square miles of central and inner London out to (but not including) the North and South Circular roads. Owners of motor vehicles driven within it that don’t comply with the required environmental standards have to pay a £12.50 daily charge or face a fine. If the August enlargement goes ahead, ULEZ rules will apply across all of Greater London’s 600 square miles.

Opposition to the enlargement includes a legal action launched in February by four Conservative-run outer London boroughs – Bexley, Bromley, Harrow and Hillingdon – along with Surrey County Council (also Tory). The High Court has given consent for a judicial review to be conducted on two of the five grounds applied for.

One of those grounds is that the proper legal procedures were not followed when the expansion plan was advanced. The other is that people who don’t live in Greater London but drive into it should have been considered for inclusion in Transport for London’s scrappage scheme, which is making £110 million available to help certain categories of non-compliant vehicle owner to upgrade. A decision is expected in July.

Policies for improving air quality in London have been central to Khan’s mayoralty ever since he was first elected in May 2016.

He brought forward by a year the launch date for the original ULEZ, which covered the same eight square mile area as the central London congestion charge zone. The first of its kind in the world, the ULEZ was devised by Khan’s Conservative predecessor Boris Johnson and came into effect on 8 April 2019 in addition to the congestion charge, which was £11.50 per day at the time. The ULEZ was preceded from 23 October 2017 by a temporary £10-a-day “toxicity charge” supplement on pre-Euro 4 standard vehicles, typically those registered before 2006.

On 25 October 2021, the re-elected Khan greatly enlarged the ULEZ so that it encompassed an area inhabited by 3.8 million of London’s population of around nine million. The measure had been included in his manifesto for the delayed 2021 mayoral election, but expanding the zone still further was not. Neither was it included in his statutory transport strategy, published in March 2018.

That meant he had to augment his transport strategy with a supplementary proposal to “seek to address the triple challenges of toxic air pollution, the climate emergency and traffic congestion through road user charging schemes including by expanding the Ultra-Low Emission Zone London-wide”.

The backing of London Assembly members needed for this was secured last November. That paved the way for announcing a few days later that the London-wide enlargement would go ahead.

The Arguments

Sadiq Khan maintains that taking the ULEZ all the way out to the Greater London boundary will accelerate and help eventually eradicate the most polluting motor vehicles from all of London’s roads. Although the addition to his transport strategy talks about it addressing a “triple challenge”, he and Transport for London (TfL) tend to emphasis the health benefits they say the change will bring.

TfL cites the most recent (2019) London Atmospheric Emissions Inventory, a measurement of pollutants compiled from data it gathers with the help of others, including Imperial College, to say that despite recent improvements, “road transport is the single biggest contributor of nitrogen dioxide (NO2) and particulate matter in Greater London”.

It is an accepted medical fact that nitrogen gases and microscopic particles contribute to people developing lung cancer, heart disease and respiratory conditions including asthma, whose symptoms are worsened by poor air quality. A 2015 study by researchers at King’s College concluded that 9,500 Londoners a year were dying prematurely due to long-term exposure to NO2 and to the smallest particulates, known as PM2.5. Asthma, says TfL, is suffered from by “more than 500,000 Londoners” of whom over half live beyond the North and South Circular roads.

The Mayor himself contracted the condition when in his forties. And, for him, the harm done to health by toxic road transport emissions is unacceptable, a view reinforced by the death following an asthma attack in 2013 of a nine-year-old girl who lived near the South Circular. Ella Adoo-Kissi-Debrah was the first person to have air pollution listed as a cause of their death, with Southwark Coroner’s Court finding it had “made a material contribution” to it.

Khan therefore considers it right to impose charges and fines on people whose vehicles produce the highest quantities of emissions damaging to health in order to persuade them to drive less or to purchase replacement vehicles that do less harm.

However, the Conservatives strongly disagree that the policy is justified. They argue that the ULEZ expansion is unnecessary because the number of non-compliant vehicles will inevitably reduce anyway as they wear out, and that further widening the scope of the ULEZ won’t even make much difference to air quality as it is. A TfL report on the effects of the previous expansion six months after it took place found that it had added little to the substantial improvements brought about by the original, much smaller, central London scheme.

The Tories allege that the expansion’s true purpose is to make money for TfL – whose finances are in a fragile state – at the expense of vehicle owners who can least afford it amid a cost of living crisis. And they argue that it will be bad for the economy because it will hit small businesses which either depend on cars and vans to get around or, in the case of retailers, on customers driving to their premises (including from outside Greater London).

The Conservative claim that the ULEZ expansion will have little affect on air quality is based on parts of the independent impacts assessment conducted for TfL by technical professional services firm Jacobs and released in May 2022. This says the scheme will bring about a “moderate positive” reduction in NO2 pollution across Greater London and a “minor positive” one in PM2.5 and larger PM10 particles, along with a “neutral” impact on carbon emissions, relevant to climate change.

The Jacobs assessment also says there will be an overall “minor negative” impact on the objective of providing affordable and safe transport choices for all, with a “disproportionate impact on people on low incomes” including those who travel using non-compliant vehicles for work, perhaps at night, and for other reasons.

As with all road user charging schemes at present, the ULEZ daily charge is the same for everyone and therefore relatively more expensive for the less well-off. A resulting reduction in commuters entering Greater London from outside is also judged a “minor negative”.

However, the Jacobs assessment also says there will be “minor positive” improvements in health outcomes for Londoners, disproportionately so for older people and children and particularly so for “people with a range of long-term health conditions, children and older people living in outer London”.

And a separate quantitative health assessment by environmental consultants Ricardo (Appendix A) concludes “it is clear that the proposed scheme would bring about important reductions in the health impacts associated with air pollution in Greater London”. It continues: “The improvements in health outcomes with the proposed scheme are greatest in outer London where the biggest reductions in population-weighted mean concentrations of NO2 and PM are seen.”

More recently, in January this year, London Assembly members were told that TfL’s estimate of the income it will receive in the first year of the expansion’s operation is around £200 million (and could be 50 per cent higher or lower), with this figure reducing to “negligible” by 2027 as the number of non-compliant vehicles falls (just under £100 million came in during the first year of the initial ULEZ expansion).

In February, City Hall a one year on report, peer reviewed by King’s College’s Doctor Gary Fuller, concentrated on the combined effects of the entire ULEZ area together with that of the Low Emission Zone (LEZ), a measure brought in by London’s first Mayor, Ken Livingstone, in 2008 to regulate heavy vehicles, whose standards had been toughened in March 2021.

This found that cumulatively since 2019 there had been a reduction of 23 per cent in all nitrogen emissions across all of London compared to what they would have been without a ULEZ, and one of 26 per cent within the ULEZ area. PM2.5 was also down, by seven per cent across all of London and by 19 per cent within the ULEZ. The report also said that “following the ULEZ expansion, there have been reductions in traffic levels both inside the zone and outside the zone and also on the boundary roads, compared to the pre-ULEZ expansion period”.

Also in February, BBC London transport and environment correspondent Tom Edwards heard from Imperial’s Professor Frank Kelly that London still doesn’t meet World Health Organisation air quality guidelines: “Everywhere you go the air you are breathing is having some impact on your health”. Speaking of the latest expansion plan, Kelly’s said: “The ULEZ will lead to an improvement in air quality and traffic emissions and that means air quality will improve, and when we see improvements in air quality we see health benefits”.

Insofar as any common ground exists it is that a Londonwide ULEZ will penalise some in one way (motoring costs) and benefit all in another (cleaner air). The serious part of the argument is about the relative weights that should be assigned to the respective wins and losses. Will the air quality upside be worth the downsides for those who have to buy a new car or van, or find their businesses adversely affected?

(Further reading: the House of Commons library has produced a clear and detailed account of the ULEZ expansion plan and its possible implications).

The Politics

The Conservatives and their media allies think hostility to the ULEZ expansion gives them hope of becoming competitive in next year’s election, despite their party being deeply unpopular in London. It also excites their enduring dislike of road user charging, which goes back to Ken Livingstone bringing in the congestion charge in 2003.

Even though Boris Johnson retained Livingstone’s congestion charge zone (albeit he did away with the western extension of it, added by Livingstone in 2007) and committed to the original ULEZ, the Tory London Assembly group’s hostility has been unstinting.

The seemingly visceral character of their opposition may help explain their lengthening record of misrepresenting road pricing issues to the point of fabrication and beyond.

In 2020 they insisted that Khan had increased the level and operating hours of the charge of his own volition when, in fact, the government had told him to as a condition of receiving emergency funds during the pandemic.

Throughout the 2021 election campaign they invented an impending so-called “outer London tax” based on TfL responding to a government demand for suggestions for raising extra revenue by outlining a theoretical boundary charge on non-Londoner motorists. A boundary charge has never come near being adopted as a mayoral policy.

Such behaviour has been repeated with the ULEZ expansion plan: the balance of responses to the official consultation, more of which were anti than pro, has been termed by the Tories and their allies a “vote” or a “poll” which the Mayor has outrageously ignored, as if a consultation were a referendum; they commissioned an opinion poll which characterising the plan as a revenue-raising ruse rather than a means of improving air quality.

It remains to be seen how effective such tactics are. A poll commissioned by City Hall in October which described the ULEZ’s purpose as tackling air pollution found 51 per cent of Londoners in favour overall compared with only 27 per cent against. Khan is regarded as quite a cautious politician, inclined to calculate electoral percentages rather than take avoidable risks. It seems unlikely he would have pushed ahead if he’d feared doing so would end in tears.

Perhaps, too, the noise the ULEZ row has generated will turn out to be greater than its electoral significance. TfL said in March that nine out of ten cars seen driving in Outer London on an average day now meet ULEZ standards and that by August the percentage will be still higher.

It calculates that fewer than 200,000 vehicles (and falling) will be affected. Around 30 per cent of outer London households don’t own or have access to a car. Will such numbers convert into enough angry voters to represent a serious threat to Khan, given that plenty of unhappy motorists will be Conservative supporters anyway?

The ULEZ war is producing a great deal of obscuring smoke and its first casualty has been truth. Only after the Tories have chosen their mayoral challenger to Khan and the first election build-up opinion polls appear will the state of the air pollution battleground become clearer.

Updated 3 May 2023, primarily to include the TfL six month report and the City Hall one year report. Follow On London on Twitter and Dave Hill on Twitter

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Categories: Analysis


  1. Linda Wilkinson says:

    Sadly the stats pedalled here from Imperial, home of flaky research and relating to number of deaths are not support by TFL’s own reports. Whatever way you look at it , Khan is clobbering Londoners in the lower economic brackets and businesses, both small and medium sized.
    It’s an awful policy, under resourced and deserves axing. Not the right answer, not the right approach.

    1. MilesT says:

      Most of the stats *peddled* here are from King’s, not Imperial (read carefully), with no Imperial stats specifically referenced (only descriptions of general impacts), and TfL report includes/references Imperial’s work (amongst’s others)

      Please be specific as to the precise discrepancy of death figures (given that only one death certificate to date references air pollution; other may reference asthma or respiratory where air pollution may be a cause but not definitively identified)

  2. MilesT says:

    A softened implementation of ULEZ expansion would address many of the concerns although deliver reduced revenue–and revenue will decline over time unless the required emissions standard is periodically increased (e.g. Euro 4 to Euro 6/7 for petrol, Euro 6 to Euro 7 for diesel; and ultimately some reduced toll levied on all vehicles for tyre and brake emissions).

    Examples of softening
    * Allowing residents within ULEZ and some adjacent boroughs to have a number of free or heavily discounted journeys per month (annualised for flexibility) for non-compliant vehicles currently owned (registered to a ULEZ account). Not enough for daily driving, but enough for occasional social use, maybe off peak only. For example, 3 per month (reducing slowly over remaining years). No allowance for non compliant vehicles registered to London addresses after ULEZ implementation date (or maybe one more permitted on payment of an up front fee covering 75% of the foregone ULEZ revenue from free allowance days)
    * Treating ULEZ charge not as a fee but as a mandatory contribution to a scrappage payment to residents when the non-compliant vehicle is scrapped (not sold, scrapped), so the user eventually will get a deposit to buy a compliant vehicle.
    * Allow one ULEZ charge to be reclaimed whenever a noncompliant resident’s vehicle is scrapped or sold to a buyer outside the ULEZ zone–unfair to have to pay ULEZ to drive the vehicle to a scrapyard or to a new owner (and also unfair to have to pay a towage/transport charge to avoid the ULEZ for such vehicles)
    * Exempt heritage vehicles sresihould not be totally exempt, but should have an allowed number

  3. JohnC says:

    Imperial, one of the world’s renowned universities for research, offers ‘flaky research’? Only if you disagree with its conclusions I suspect.

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