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High Court ruling on air pollution casts fresh doubt on the deliverability of Heathrow expansion

2nd November, 2016

The Government has failed to take adequate measures to meet the legal requirement to being levels of nitrogen dioxide to within legal limits as soon as possible, the High Court ruled today, and has fixed its estimates for compliance dates based on over-optimistic modelling of pollution levels. Today’s judgement discredits the air quality plan that formed the basis for the Government’s argument that a new runway at Heathrow would neither cause not exacerbate legal breaches in NO2 levels.

This is the second time in just 18 months that the legal organisation ClientEarth has scored a court victory on this issue. In April 2015 the Supreme Court ruled that the Government’s plans for bringing the UK into compliance with air quality laws were inadequate, and ordered that the document must be redrawn. An updated plan was published by the end of 2015. This brought forward the anticipated date of compliance to 2025 for London – just in time for the opening of a new runway according to the Airports Commission’s anticipated timeline. But the plans appeared to rely on new, more optimistic forecasts of emissions from diesel vehicles without presenting substantive policy proposals to actually deliver improvements.

AEF has consistently challenged the robustness of the Government’s plans for air pollution and has argued that given the conclusion of the Airports Commission that expansion at either Heathrow or Gatwick would lead to a deterioration in air quality, a new runway at either location should not be approved until the Government could be confident that air pollution in London and the South East would be within legal limits. Our summary of 50 reasons why Britain doesn’t need a new runway sets out why air pollution, alongside climate change, noise and other impacts, presents a significant hurdle in the way of expansion.

A report published today by IPPR suggests that the Heathrow area – which suffers pollution both from road transport (including freight vehicles) and from aircraft – will contain multiple points at which legal limits will continue to breach 2025 even if radical policy measures are taken in the interim. A ‘near total phase out of diesel cars in inner London, and a move toward more sustainable alternatives across other road transport’ would bring most of the city into compliance, the report suggests, but with numerous ‘concentration points’ above the NO2 limit value persisting in the vicinity of the airport.

AEF Deputy Director Cait Hewitt said: “Today’s ruling leaves the Government’s defence on the air pollution challenge facing a third runway in tatters. Relying on optimistic modelling, rather than real policy measures and appropriate planning decisions, has been found to be not just immoral but illegal. Expansion at either Heathrow or Gatwick would increase air pollution, the Airports Commission found. The Government should drop its plans for new runways and focus instead on tackling London’s air pollution crisis.”


Figure 4.2 in IPPR's report Lethal and Illegal: solving London's air pollution crisis, November 2016

Figure 4.2 in “Lethal and Illegal: solving London’s air pollution crisis”, IPPR, November 2016