Despite evidence of harm and London’s clean-air commitments, most borough councils continue to operate fleets dominated by diesel vehicles. Our Freedom of Information requests to all 32 London boroughs show that most councils across London continue to run diesel-heavy fleets despite the well-established health effects of air pollution, and the capital’s ambition to cut road-based emissions.
Council fleets include the vehicles that local authorities use every day to deliver services, such as bin lorries, street-cleaning vehicles, maintenance vans and transport used by housing, highways and parks teams. These vehicles operate extensively within neighbourhoods, often on residential streets, meaning their emissions directly affect the communities they serve.
While air pollution affects everyone, it disproportionately harms children, people from racially minoritised communities, and those living in lower-income neighbourhoods.
Of the councils that replied, seventy-one per cent confirmed that diesel makes up the majority of their fleet [1]. Electric vehicles account for 21%, far short of the scale required to meet London’s clean-air commitments.
In some boroughs, diesel vehicles remain almost universal and the picture varies dramatically by borough. Hillingdon sits at the bottom of the table, with 97 per cent of its vehicles still running on diesel. Councils with the highest percentage of diesel vehicles in fleet were as follows:
Despite the number of diesel cars registered in London falling by 44 per cent between 2019 and 2023, some authorities are still expanding diesel fleets: Havering has added one hundred new vehicles to their fleet in five years, every one of them diesel, as reported in TfL’s Car ownership trends report in 2024 (pdf).
A handful of councils demonstrate that transition is possible. Lewisham has almost completed the shift, running 285 electric vehicles and only four diesel vehicles. Westminster has just two diesel vehicles left. The councils leading the transition to electric, with the highest proportion of electric and hybrid vehicles were:
The health consequences of diesel pollution are well-established. Diesel engines emit nitrogen dioxide (NO₂) and fine particulate matter (PM2.5), both proven to damage heart and lung health. The World Health Organization classifies diesel exhaust as carcinogenic to humans and research from Public Health England estimates that air pollution contributes to around 4,000 premature deaths in London annually.
These harms are not distributed evenly. According to the government’s data, urban areas are home to a higher proportion of households living in poverty compared to rural areas, and there is extensive evidence of a strong correlation between low incomes and poor health.
National policy is moving firmly towards phase-out, and the sale of new petrol and diesel cars will be banned from 2030, with hybrids permitted until 2035. New non-zero emission HGVs (≤26 tonnes) are not banned until 2035, and larger trucks until 2040. Yet many London councils, public bodies responsible for maintaining local environments, continue operating diesel-heavy fleets with little apparent urgency.
At Impact on Urban Health, we recognise the financial and logistical pressures local authorities face, but the health consequences of inaction are stark. Public bodies should be leading this shift, not making matters worse.
But some boroughs have proven that rapid transition is possible. The challenge now is ensuring that all Londoners, regardless of where they live, can benefit from cleaner air equally. Councils must be supported to make the switch to cleaner vehicles.
We’re calling on councils to reduce emissions from vehicle fleets by transitioning from diesel and petrol fuelled vehicles, to zero exhaust emission fleet. To help accelerate the transition, we’re calling on the Greater London Authority (GLA) to introduce mandatory transparency requirements for London boroughs on action on air quality.
You can read more about our work to reduce air pollution from freight here.
Footnotes
[1] The analysis presented here reflects the data provided by councils that responded in full or in part. Barking, Camden, Croydon, Ealing, Enfield, Haringey, Harrow and Sutton did not respond to the Freedom of information request.
Image credit: Photo by Anouk van Ravenhorst on Unsplash
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