The Planning / Legal Issues Surrounding Heathrow’s Third Runway

03 Nov 2016

Airport expansion has been a question the Government has had to answer for many years as globalisation and emerging economies require an upgrade of the UK’s aviation infrastructure.  Last year, the study by the Airports Commission backed Heathrow’s third runway and considered Gatwick and a rival hub proposal to be viable but inferior.

On 25 October, a Cabinet sub-committee, chaired by the Prime Minister, unanimously decided to back a third runway at Heathrow.  Teresa May said:

“Airport expansion is vital for the economic future of the whole of the UK and today also provides certainty to Londoners. Businesses will know that we are building the infrastructure they need to access global markets… By making sure we improve the links between regional airports and our capital city we can use airport expansion as an opportunity to bring the UK closer together… This decision demonstrates that as we leave the EU we can make a success of Brexit and Britain can be that open, global, successful country we all want it to be.”


On the topic of the environment, Transport Secretary Chris Grayling confirmed that independent advice had concluded that the new runway is deliverable within air quality limits and that Heathrow would commit to air quality impact mitigation.  He confirmed that development consent would not be granted if it impacted on the UK’s air quality obligations.


This is a controversial decision.  Since the announcement:

  • Conservative MP for Richmond Park, Zac Goldsmith, has resigned, honouring his pledge to quit as a Conservative MP and stand as an independent in the by-election;
  • Putney MP Justine Greening (Education Secretary) has made public her disappointment;
  • Greenpeace has joined four Conservative authorities in the area (Windsor and Maidenhead – Theresa May’s own local authority, Hillingdon, Richmond upon Thames and Wandsworth) to prepare grounds for a joint legal challenge against Heathrow expansion;
  • London Mayor Sadiq Khan, elected on an anti-Heathrow expansion manifesto, has stated: “I will continue to challenge this decision and I am exploring how I can best be involved in any legal process over the coming months”; and
  • Boris Johnson has predicted the delivery of the third runway will be caught up in legal challenge, “I think it will be very likely it will be stopped.  We have been here before and we are going to see an inevitable fight in the courts and I think the chances of success for the proponents of the third runway are not high.”


The proposal

Heathrow now:  

Passengers                      80m

Flights                             480,000

Heathrow’s northwest runway expansion:

Passengers                      130m

Flights                            740,000

Cost                                £16.5bn

Residential Properties lost 950

Opening date                     2026


  • Passengers will have a greater choice of airlines, destinations and flights
  • A £2.6bn package of compensation for local communities
  • Economic benefits worth up to £61bn over 60 years; up to 77,000 additional local jobs over the next 14 years
  • Costs will be met by private sector, not taxpayer
  • The government will propose a 6½-hour ban on scheduled night flights and more stringent night noise restrictions


Potential challenges

Can the announcement be judicially reviewed?  There have been reports that a local groups are looking to challenge the announcement on a number of grounds, including bias.  If an opponent tried to judicially review the announcement, it could be difficult to argue that this is an administrative decision rather than a policy preference being explored and considered in the draft national policy statement.


The Government will now take the scheme forward in the form of a draft national policy statement to be laid before Parliament.  This is a statement of national policy which will establish the case for the third runway and set out the framework for decision-making.  This is likely to come forward soon, ready for public consultation .  We can expect opponents to be submitting robust consultation responses, supported by expert environmental reports.  These will be considered by the Government with the final vote on the national policy statement by Parliament expected in late 2017 / early 2018. 


The decisions following this could be subject to judicial review.   The HS2 judicial review contained grounds of challenge relating to the inadequacy of the consultation process.  The 2010 judicial review of the then proposed Heathrow expansion focussed on the consultation process and subsequent decisions.  This judicial review also gives us an idea of what decisions could follow, including:

  • possibly undertaking a strategic environmental assessment which could be required under EU Directive;
  • the adoption of the national policy statement;
  • the grant of development consent, following a long application and consultation process including environmental impact assessments and an examination; and
  • the grant of consents under the Civil Aviation Act.


DMH Stallard have a dedicated team of Planning specialists who can advise on all Planning related matters. For more information contact:

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