The Airports Commission has decided not to shortlist the Thames Estuary as an option for increasing airport capacity.
The proposal had been dubbed ‘Boris Island’ because of its support from the London Mayor, Boris Johnson. The Isle of Grain scheme was predicted to cost from £70bn to £90bn.
But following a feasibility study, the Commission said it had concluded the Thames Estuary proposal had “substantial disadvantages that collectively outweigh its potential benefits”.
The decision leaves three schemes left in the running: two at Heathrow, and one at Gatwick.
Johnson called the decision “myopic”, and said his proposal was not dead.
Airports Commission chair Sir Howard Davies said: “We are not persuaded that a very large airport in the Thames Estuary is the right answer to London’s and the UK’s connectivity needs.
“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. Even the least ambitious version of the scheme would cost £70bn to £90bn with much greater public expenditure involved than in other options – probably some £30bn to £60bn in total.
Davies said the Commission would now continue its appraisal of the three shortlisted proposals for additional capacity and will publish the appraisal for public consultation in the autumn.
Johnson said the Commission’s decision had “set the debate back by half a century”.
He added: “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 also insisted the island airport plans were not dead.
“Proposals to expand either Heathrow and Gatwick will run into hurdles - as they had done in the past - and any future government will return to the Thames estuary plan,” he predicted.
The three remaining options are:
a proposal from Gatwick for an additional runway to the south of the existing runway;
a proposal from Heathrow for an additional runway to the north west of the existing northern runway;
a proposal from Heathrow for an extension to the existing northern runway, which would operate as two separate runways.