The case for expansion at Heathrow airport was given a shot in the arm this morning as a new, independent study revealed a third runway would not breach emissions laws.
Pollution around the west London airport - the busiest in Europe - has been a major sticking point in its bid for a third runway, with campaigners arguing air pollution levels at points around the airport already exceed international rules.
A study from the University of Cambridge, out this morning, however, claims advances in low-emissions airlines and cleaner forms of cars and public transport around the airport, mean a third runway would not lead to a degradation of air quality around Heathrow.
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Professor Rod Jones said: "If there is the development of a third runway, we expect there to be a marginal increase in nitrogen dioxide (NO2) coming from the airport itself. But that would be against the background of reduced NO2 from other traffic because of Euro 6 engines [new guidelines on acceptable pollution levels from cars] and electrification of the traffic fleet."
Jones and his team at Cambridge placed 40 sensors at key points around the airport to level current emissions, before using the data to model how those levels would change where a third runway to be given the green light.
The study has been seen by the BBC, which verified that the work has "no formal links to any airport or the government."
A decision over whether to expand Heathrow or Gatwick will be made "soon", Theresa May confirmed yesterday in her speech at the Conservative Party Conference. Despite fears of a delay, the Prime Minister indicated at least one will be chosen for expansion when she signalled the UK could not duck "controversial" infrastructure decisions such as Hinkley Point, HS2, fracking and airport expansion.
The Airports Commission recommended expansion at Heathrow at the end of last year, arguing it provided significantly more economic benefits than a second runway at Gatwick would. To address local concerns, the body suggested limits on flight times and other restrictions.
Gatwick has rejected the findings of the Commission, arguing its data on passenger numbers is more than a decade out-of-date given rapid growth at the Sussex airport. The government has delayed the decision on multiple occasions, and there are thoughts whatever decision is taken will be subject to lengthy legal proceedings and judicial appeals from the losing side.