What is happening with Heathrow’s proposed third runway?
The government has put big infrastructure at the heart of its strategy to kickstart economic growth – particularly if paid for through private investment – and has vowed to make building easier. Few projects come as big, or at such an advanced stage of planning, as Heathrow’s expansion. With record numbers of passengers, Europe’s busiest airport is at capacity, and it has new owners with deep pockets who see an opportunity to invest.
Didn’t it already get permission to build a runway – what happened?
Yes, more than once. The Conservatives overturned Heathrow’s original plan, which was approved by Labour in 2009, before setting up an independent airports commission, which found a new runway was needed. The plans were endorsed by the government and voted through parliament in 2018, and were eventually upheld by the courts. But then Covid happened, passengers disappeared, and Heathrow never submitted a full planning application.
So are these new plans?
They are fundamentally the same as last time, but Heathrow now believes it can pack in even more flights and passengers – up to 150 million a year – due to bigger planes and operational advances. It will cost more too because of inflation: £21bn for the runway; another £12bn to expand its terminals; and a further £15bn to upgrade the rest of the airport to match.
Will the runway still go over the M25?
Part of the engineering challenge is getting a runway over Britain’s busiest motorway, the M25 orbiting London, at one of its most congested points. At a cost of £1.5bn, Heathrow plans to build a new stretch of M25 further west, with the runway going over the top, ready for cars to be switched overnight and allow it to complete the rest of the two-mile strip. It believes this is still better value and more efficient than situating the runway further to the east, which would mean demolishing more houses and putting much more of west London under noisy flightpaths.
What happens next?
The government is officially reviewing the plan, as well as an alternative proposal submitted by the Arora group, alongside the existing airports national policy statement, to “ensure that any scheme is delivered in line with our legal, environmental and climate obligations”.
A response is expected in early autumn and, if green-lit, Heathrow could launch a formal public consultation before submitting a full planning application. However, its new owners, which include Saudi Arabia and Qatar, want to be sure that the legal and political context has shifted enough for its near-£50bn investment plans to come to fruition.
That means passing the planning bill, so neither bat, newt, nor judicial review blocks the runway. It also hopes for progress on airspace modernisation, to ensure the additional 750 planes a day can fly over London as required; and most of all, guarantees that the Civil Aviation Authority will let Heathrow charge airlines enough to recoup its investment.
What about net zero?
What indeed. The airports commission view a decade ago was that a third Heathrow runway could be compatible with the UK’s climate commitments, so long as other aviation growth was constrained. However, airports around the UK are also now looking to expand, not least Heathrow’s London rivals. Stansted’s growth was enthusiastically endorsed at an early Labour “growth summit” and the transport secretary, Heidi Alexander, has given the green light to plans to double the size of Luton airport. She has also said she was minded to approve Gatwick’s second runway plans, with a decision expected soon.
What’s the good news?
Tens of thousands of jobs created, economic growth, and competition, cheaper fares and new destinations for passengers flying from Heathrow.
And the bad?
Another 276,000 flights a year overhead, adding to noise and air pollution. Locally, 750 homes bulldozed, and years of disruption in construction for the rest. And an estimated extra 4.4m tonnes of CO2 a year from resulting flights, contributing to the climate emergency.
