London mayor’s plan for airport in Thames estuary dismissed by panel

London Mayor Boris Johnson's plan to replace Heathrow with a new airport on an island in the Thames estuary has been dismissed by an official study as too expensive and complex to address Britain's aviation needs.

Costing upwards of £70 billion (HK$900 billion), a four-runway hub on the Isle of Grain east of London - nicknamed "Boris Island" - would cause huge economic disruption and pose potentially insurmountable environmental concerns, Airports Commission chairman Howard Davies said yesterday. Davies will now examine plans to expand Heathrow or establish a secondary hub at London Gatwick before coming up with a shortlist of options.

"There are serious doubts about the delivery and operation of a very large hub airport in the estuary," Davies said in a statement. "We need to focus on solutions which are deliverable, affordable, and set the right balance for the future of aviation in the UK."

For Johnson, the state-appointed body's findings come as a setback weeks after he announced plans for a return to national politics in a move that could presage a bid to succeed David Cameron as prime minister. The Conservative politician said in a statement that Davies had rejected the "only credible option" and that its future work will "become increasingly irrelevant".

Heathrow, Europe's busiest airport, attracted 72 million passengers last year, despite being restricted to just two runways, as carriers switched to bigger planes to help eke out capacity. Proposals for a £14 billion expansion include building a third landing strip or extending an existing one.

Gatwick, the world's busiest single-runway airport, said it could construct a second strip for as little as £5 billion. The two airports are already lobbying for Davies' backing, though the commission isn't due to report until after the 2015 election. Johnson said Davies had been deterred from backing the estuary option "simply because of its sheer scale and vision".