Boris Johnson's plan for a four-runway hub airport in the Thames Estuary has been rejected, the Airports Commissions has confirmed.
The government-backed body led by Sir Howard Davies said a new hub airport “was not the answer” to London’s and the UK’s connectivity needs, and it wouldn’t “justify the enormous costs involved”.
The project, dubbed 'Boris Island' because of the mayor's backing, was one of the options being considered to help expand the UK’s airport capacity in the south east of England.
The decision leaves the Commission with three remaining options - a third runway at Heathrow, extending an existing runway at Heathrow, or a second runway at Gatwick.
Davies said in the Commission’s report: "While we recognise the need for a hub airport, we believe this should be a part of an effective system of competing airports to meet the needs of a widely spread and diverse market like London's.
"There are serious doubts about the delivery and operation of a very large hub airport in the estuary.
"The economic disruption would be huge and there are environmental hurdles which it may prove impossible, or very time-consuming to surmount," Davies said.
How a Thames Estuary airport would have looked
Johnson's proposal for a new four-runway hub on the Isle of Grain to the east of London would have cost more than £100 billion.
The London Mayor said he was disappointed by the decision and in one “myopic stroke” the Commission has set back the debate back by half a century.
"Gatwick is not a long term solution and Howard Davies must explain to the people of London how he can possibly envisage that an expansion of Heathrow, which would create unbelievable levels of noise, blight and pollution, is a better idea than a new airport to the east of London that he himself admits is visionary, and which would create the jobs and growth this country needs to remain competitive,” Johnson said.
"It remains the only credible solution, any process that fails to include it renders itself pretty much irrelevant, and I'm absolutely certain that it is the option that will eventually be chosen."
Heathrow CEO John Holland-Kaye said following the decision to reject the Estuary plan he urged Johnson to back Heathrow in the race for airport capacity.
“We have always agreed with the Mayor that Britain needs a successful hub airport to compete in the global race for jobs and growth," said Holland-Kaye.
“Heathrow is now the only hub left in the race. We would like to work with the Mayor to deliver Heathrow expansion in a way that benefits the whole country while reducing noise impacts for local people compared to today.”