This week, on the 26 August 2014, Boris Johnson launched a last ditch attempt to keep his plans for the relocation of Heathrow in the Thames Estuary alive. The Airport’s Commission is due to decide, within a matter of weeks, whether ‘Boris Island’ should be added to a shortlist of options to expand aviation capacity. A City Hall report entitled ‘Gateway to our future: why the UK needs a new hub airport’ looks to convince the Airport’s Commission of the feasibility of Boris’ grand vision.

Boris’ desire for a brand new hub airport is unlikely to come as a surprise for most, much has already been made of his ambitious plans within the media. This is the first time, however, that a direct comparison of each of the options being considered by the Commission has been undertaken. The options to expand aviation capacity shortlisted by the Commission are a second runway at Gatwick or a third runway at Heathrow (in the form of a separate runway or the extension of an existing runway). Should the relocation of Heathrow be added to this shortlist?

The report acknowledges that an additional second runway at Gatwick is needed but is sceptical of the feasibility of adding a third or fourth due to its locational constraints. Additionally, creating an extra runway at Heathrow carries a political delivery risk – demands for a fourth runway will be inevitable if a third is built, a case of the recurrent argument ‘just one more’.

So how does the case for the relocation of Heathrow stack up? The report determines that London is in need of increased economic activity to the east of the city. The creation of a four-runway airport in the Thames Estuary would restore the imbalance between west and east London and ignite a wider regeneration effort. Alongside this, it is proposed that the old Heathrow site could be transformed into a new city, providing much needed homes and jobs. It is made clear that these plans are believed to be more beneficial for London and the UK in the long term, safeguarding the country’s growth and London’s status as a global city. Stockholm, Denver and Munich, amongst others, are given as examples where airports have been successfully relocated.

Yet care needs to be taken when considering the viability of such a scheme, feasibility and costs need to be matters considered with the greatest of depth and detail. In addition, the report cites other cities where airports have been effectively relocated, yet we must bear in mind the uniqueness of cities. What works in Denver may not necessarily work for London. Moreover, when looking to cities that have successfully relocated their airports it becomes clear that London will need certain structures in place for such a feat to be a success: strong political leadership; support from businesses and communities; a steady economy; and planning certainty.

One of the more controversial downsides of moving Heathrow to the east will be the shutting of its current site. Though Boris believes the site could eventually be transformed into a thriving new city, this is something that will not be achieved overnight. The west will lose their magnet of economic activity, the repercussions of which may be greater than just ill feeling.

It is tricky to determine whether this report is simply an ambitious politician’s vanity project or a logical proposal to safeguard London’s economic and commercial future, and it is perhaps easier to dismiss Boris’ plans as outlandish than to commit to a project of a scale this country is not accustomed to.