Heathrow expansion: Why new runway is still years away despite government decision

Ministers are expected to back the decision to build a third runway at Heathrow airport today - but there will still be a number of hurdles to overcome before it is built.

The successful bid - whether it is at Heathrow or Gatwick - will have to deal with legal challenges, mounting protests, a public consultation and a vote in the Commons before a new or extended runway can be built.

Four Conservative-run local authorities - Windsor and Maidenhead, Richmond, Hillingdon and Wandsworth - have teamed up with Greenpeace and instructed lawyers to prepare a case if a third runway at Heathrow gets the go-ahead.

Proposals: Heathrow is hoping to get the go-ahead for a third runway at Heathrow (Rex)

Expansion: The new runway would be 3,500 metres long (Your Heathrow)

More passengers: The new Terminal would be at the west of Terminal 5 (Your Heathrow)

The exact nature of the challenge will be decided once the details of the decision are known.

The group worked together in 2010 to win a High Court battle over the plans of Gordon Brown’s government to expand the west London hub.

Further to that legal challenge, the Sussex and Surrey branches of the Campaign to Protect Rural England and more than a dozen local action groups have written to Prime Minister Theresa May to warn that they would “consider a legal challenge” of their own against Gatwick expansion, delaying any planned construction.

Protests: Climate change protestors will mount more opposition to the plans (Rex)

Unhappy: Locals have been campaigning against the runway for years (Rex)

Life-changing: Residents say they will be forced to move if the plans go ahead (Rex)

It is unclear whether Heathrow or Gatwick would attempt to go to court themselves to challenge any decision rejecting their proposals - much will depend on whether businesses are in favour of going ahead with whatever is decided.

Even if the Government does, as is expected, back Heathrow for expansion, Gatwick bosses have insisted the airport would be "standing ready to deliver” a second runway if it turns out that the Heathrow plan cannot be delivered despite being selected. iframe src=“https://www.yahoo.com/heathrow-gatwick-map-potential-runways-075301303.html?format=embed®ion=GB&lang=en-GB&site=news&player_autoplay=true” width=“640” height=“360” allowtransparency=“true” data-yom-embed-source=“{media_id_1:14b3202c-1cf6-3869-91c7-90aca44f7fb2}” frameborder=“0”>

Aside from legal issues, a decision for a new runway at Heathrow will almost certainly trigger more protests from residents worried about local impacts and environmentalists concerned about climate change.

Direct action by green campaigners may intensify, and there will likely be similar scenes to when activists chained themselves together on Heathrow’s northern runway in July last year.

A public consultation will be held on the effects of airport expansion, followed by a final decision by the Government, which will be part of a National Policy Statement on Aviation.

Improvements: Artist impression of the inside off a a new terminal at Heathrow (Your Heathrow)

Green campaigners fear Heathrow’s expansion will add to climate change (Rex)

This will be put to the House of Commons for a vote in the winter of 2017/18.

However, a free vote in the case of Heathrow expansion would allow ministers like former London Mayor Boris Johnson and Justine Greening to officially oppose the decision without the need to resign.

Support for a third runway at Heathrow is high among MPs, with some 67% in favour of it, according to the results of a poll published by Heathrow in September.

Passion: Protestors made their feelings clear inside the airport itself last year (Getty)

Opponents: Zac Goldsmith and Boris Johnson have long fought against Heathrow expansion (Rex)

Zac Goldsmith, who failed in his bid to become London Mayor this year, has himself insisted that he will quit his role as Tory MP for Richmond Park and North Kingston if the west London hub is expanded.

If Heathrow is selected, it would expect to receive final planning permission by around 2020.

The airport wants to add 25,000 more flights to its existing annual limit of 480,000 between 2021 and the opening of a third runway in 2025 to provide a “Brexit boost”.

Gatwick has said it can guarantee delivery of an operational second runway by 2025, with the new terminal opened in stages, based on growth in passenger numbers.

Top pic: Getty