London: shifting air traffic to the Thames Estuary?

If London wants to keep its Alpha ++ global rank, that's what it should do.

It's a radical plan and it's been kicked into touch before.  But this time it might just be a goer.

According to the Globalization and World Cities Research Network (GaWC), only New York and London boast Alpha ++ world cities ranking. The next group of cities consists of Hong Kong, Shanghai, Paris Singapore, Beijing, Tokyo, Milan and Sydney.  So, London's right up there.  But Heathrow airport's reputation in particular could damage London's positioning.

Living under the Heathrow flightpath is horrendous, as millions of Londoners can testify. And Heathrow is a national disgrace (Terminal 3!  The apalling mess which heralded the opening of Terminal 5.  The snow-stopping chaos at Heathrow last winter, as Helsinki Airport remained open when blasted by six feet of snow).

If you've travelled abroad much you'll know what I mean. You've only got to experience the facilities of Singapore, Kuala Lumpur or Hong Kong to appreciate what's possible at large airports. The ease and speed of the whole process is admirable.

Now the prospect of a third Heathrow runway has thankfully been binned, and expansions at Gatwick and Stansted also ruled out, Boris Johnson's Thames Estuary proposition looks more realistic.

A 24-hour airport with sea-bound flight approaches, accessed by rapid rail from central London, with check-ins at the rail station in town, seems like a great idea. Of course, they're now saying that the cost could be up to £70 bn. And environmentalists and Kent anti-airport campaigners have been vociferous in their opposition.  But Boris' idea has great merit.

The Thames Estuary airport concept involves building a man-made island around Shivering Sands, to the east of the Isle of Sheppey. There'd be disruption to bird and plant life. But the alternatives are expanding existing international airports (now not going ahead) or developing one of the smaller local airports in the South East (which would involve aircraft flying over urban areas).

At present, Heathrow caters for over 60 million passengers annually. Hong Kong airport at Chek Lap Kok, serving 37 million, was built in six years. It cost HK$20 bn (around £1.58 bn) and “involved four major sponsors, ten separate projects, 225 construction contracts and over 1,000 critical interfaces. The airport covers 12.48km² of reclaimed land” says airport-technology.com.

Recent estimates of up to a whopping £70 bn for the Thames Estuary plan seem steep. Originally the Kent option would take six years to complete. Can that timetable still be met?  Deputy TfL Chairman Daniel Moylan, who compiled the study, told Kent Online it's “a 20-year project, which (makes) spreading the cost "a little bit less frightening"”.

Twenty years?  I thought Boris had said six.

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