Millions near Heathrow at risk from third runway health effects, official report says
Up to three million people living near Heathrow could suffer “major adverse” health effects if a third runway is built, an official analysis has warned, as the government accelerates its blueprint for the airport’s expansion.
Health and wellbeing at risk
A report produced for the Department for Transport by the consultancy Aecom concluded that the construction and operation of the new runway would significantly harm the health and wellbeing of the most local population. The impacts would not be limited to worsening noise and air quality — the research also identified damage to access to housing, education, healthcare, open space and transport, as well as risks to water quality, community identity and cohesion, landscapes, townscapes, and climate change mitigation and adaptation.
While the report acknowledged potential benefits for jobs, income, education, skills and training, it stated: “Adverse effects are considered likely with regard to the other determinants which cover environmental and social considerations, and many of these have potential to be significant.” The document added that the impacts cannot be fully offset through mitigation measures. The DfT has been approached for comment.
Broader research underpinning the analysis has highlighted the scale of the potential harm. The Mayor of London’s office has estimated that health costs linked to aircraft noise could reach £25bn over 60 years. Separate assessments have warned that an expanded Heathrow could cause the Bath Road area to record the worst air pollution in London without mitigation, and that air pollution from the additional flights could lead to premature deaths. The expansion would increase annual capacity from roughly 84 million passengers today to 150 million, with 756,000 flights per year — producing an estimated 217,000 extra flights annually across the UK by 2055.
The draft policy that governs the project, now titled the Heathrow Expansion National Policy Statement (HENPS), sets four critical tests that any scheme must meet: a credible contribution to UK-wide economic growth, adherence to legally binding climate targets, no new breaches of air quality limits, and no increase in noise levels for residents. The independent Climate Change Committee is reviewing whether the plans are consistent with the net-zero framework.
Government pushes forward with expansion
Transport Secretary Heidi Alexander announced the launch of a 10-week public consultation on the draft HENPS, which she described as “a positive step towards realising the benefits of a third runway”. She said the government was “determined to move quickly and responsibly to set a framework for future expansion at Heathrow that will meet the needs of local people and the country on the key issues of noise, air quality, climate change and economic growth”. The consultation closes on 1 September 2026, and MPs will vote on whether to approve the policy.
Chancellor Rachel Reeves has been a vocal champion of the project, arguing that Heathrow is “not punching its weight” as a hub airport and that expansion is vital for Britain’s global competitiveness. Speaking in London, she said: “Somebody had to bite the bullet … In the last 18 months, we’ve made more progress on Heathrow than the last government made in 14 years. And I am determined that by the time of the next election, there are spades in the ground.” The government aims for a final planning decision by 2029 and expects construction to begin in 2035.
Reeves has also highlighted the economic case: an expanded Heathrow would support more than 60,000 local jobs and deliver up to £42bn in benefits to the UK, she said. Heathrow’s chief executive, Thomas Woldbye, stressed that the project is “privately funded by some of the largest investors in the world” — including Ardian, the Qatar Investment Authority and Saudi Arabia’s Public Investment Fund — and that it is “ready to go after years of scrutiny”. The runway itself, a 3,500-metre north-western strip, would require the M25 to be moved and the compulsory purchase of approximately 750 to 800 homes. The scheme is estimated to cost £33bn, with overall project costs including new terminal infrastructure and upgrades to existing facilities reaching around £49bn. Planning costs alone are expected to exceed £800m.
The previous Airports National Policy Statement was voted through under the Conservatives after the Airports Commission concluded that only one new runway could be built in south-east England without breaching climate commitments. Labour has since approved expansions at Stansted, Luton and Gatwick. The 2018 Commons vote (415-119) in favour of a third runway saw many local MPs oppose or abstain, and the Supreme Court in 2020 lifted a ban that had previously blocked a planning application.
Opposition mounts over costs and community impact
Campaigners have condemned the speed and scale of the plans. Paul McGuinness, chair of the No 3rd Runway Coalition, said the expansion was “lurching towards farce” and predicted a “decade of destruction” around the airport as homes and land are bulldozed. He warned that “whole communities could be dispersed around the country”, and drew comparisons to the HS2 rail project, arguing: “No wonder an airline boss has called it HS2 all over again. It seems extraordinary that this government seems committed to repeating those mistakes.”
Celeste Hick, policy manager at the Aviation Environment Federation, accused the government of rushing the policy through “with very little meaningful consultation with the very people” who would pay the price — “communities living under the flight paths and those whose homes will be destroyed or rendered uninhabitable”.
Airlines have also raised concerns that increased charges at Heathrow — which is regulated by the Civil Aviation Authority — could make the airport less competitive. British Airways, the largest operator, has expressed worries about a potential reduction in its slot share. Rating agency S&P Global has warned that the expansion could significantly increase Heathrow’s debt burden and push up passenger charges. Meanwhile, Greater Manchester Mayor Andy Burnham has argued that the project diverts infrastructure investment away from the North of England, and the Mayor of London, Sadiq Khan, has opposed expansion on environmental grounds.
