The debate over how to prepare London for rising air traffic has been going on for several years, and shows no signs of concluding.
The Department for Transport estimates that demand for air travel in South East England will rise to 300 million passengers per year by 2030. Current demand is 127 million.
There are two basic proposals: the addition of a third runway at London Heathrow Airport, and the construction of a new airport.
Last year, architecture firm Foster + Partners created an ambitious design for an airport on the end of the Thames Estuary, complete with a new flood barrier and high speed rail hub. London Mayor Boris Johnson supports the plan so enthusiastically, it has been dubbed "Boris Island."
Considering the necessity to alleviate air traffic in the long term, Johnson said in August:
I don’t think you can rely on Heathrow. Even if the Government was so mad and wrong to try to do the third runway or mixed-mode (mixing take-offs and landings on the same runways), those solutions would rapidly run out of usefulness and time.
But "Boris Island" has drawn criticism. Paul Griffiths, the British CEO of Dubai Airports, called it "unfundable." He told the Evening Standard:
Heathrow needs to be expanded now because of the immediate pressure on growth. Maybe Boris island is the solution for the future but I don’t think it is possible to build it in time. You’ve got all the expense of investing in that project without the productivity arising from it and at the same time you are forcing airports in the London system to become ex growth.
As the debate between the ideas continues, another, more daring, proposal has entered the fray: a floating airport on the waters of the estuary.
Gensler, an American firm, argues that the floating project, dubbed London Britannia Airport, is a "completely new approach" that will allow for expansion and minimize disruption to London residents.
Griffith's "unfundable" comment did not refer to the Gensler proposal, but a floating airport proposal would certainly face such criticism.
San Diego considered a similar idea for the Pacific Ocean a few years ago, but rejected it in large part because of its estimated $20 billion price tag.
As well as improved passenger capacity, developers of a new or revamped airport must consider the impact on carbon emissions.
Prime Minister David Cameron pledged in 2010 not to build a third runway at Heathrow, which Theresa Villiers, then the British minister of state for transport, said would invite an increase in flights that would push the country over its target carbon emissions.
Gensler says its proposal is "environmentally sensitive," as the floating airport would eliminate the need for dredging, provide a "reef-like environment conducive to marine life," and use marine turbines to generate power.
These points might offset the emissions associated with building and operating the airport; they do not address those that would be created by the increase in flights.
No decision will be made will happen in the immediate future. The UK's Department for Transport has set up a commission to consider the proposed plans. It will release initial findings next year, and a final report in 2015.
See Also: Beijing Is Building An Airport That's Bigger Than JFK, LaGuardia, And Newark Combined
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