The Global Urbanist

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Not all grand plans can be great plans: evaluating Foster's Thames Hub vision

There is much to be commended, and much to be weeded out, in Foster's vision for a new London airport in the Thames Estuary and the proposal for a new transport, utilities and data spine running the length of the country.

Kerwin Datu

Kerwin Datu

Cities: London

Topics: Integrated planning, Transport, New cities and special projects, Local economic development, Global cities

Norman Foster wants to design London's next new airport, this much is clear. Last month he launched a vision for what would be the world's largest, built on reclaimed land around the Isle of Grain in the Thames Estuary, some 55 kilometres east of central London, thus pushing himself firmly into the foreground of the political debate.

But the vision, developed by Foster + Partners with Halcrow and Volterra Partners, goes far beyond the airport, integrating a new flood barrier across the Thames, a tidal power generation facility, an 'Orbital' rail line circumnavigating Greater London as part of a new high speed line from Dover to Scotland, and a new national utilities and data corridor along the same route.

It appears that this package of proposals has been developed to lend weight to the choice of the Isle of Grain, including a means to fund its development, a sustainable method of supplying its energy, as well as an attempt to find synergies with other infrastructure developments the country will need in the long term. So how does this package stand up as a whole?

What seems to remain after these are discounted is the rhetorical synergy of selling the rail line and airport as a two-for-one package.

The Thames Barrier

The new flood barrier across the Estuary serves as a neat support act to the airport. By lowering the risk of flooding over several square kilometres of developable land, the barrier could produce large gains in land value across the region and unlock these to provide a source of funding for the airport. And by integrating a tidal power generation system within the barrier, it provides the airport with a clean, renewable energy supply throughout its lifespan.

The tidal power system can generate electricity equivalent to that consumed by 76,000 homes per year, enough to supply all the energy needs of the airport. That the airport can achieve energy self-sufficiency is a great thing in its own right … so it's a shame that it is disclosed in such a misleading way, with the vision document claiming that "hydropower … could provide electricity for up to 76,000 households", when very clearly most of it won't be used for residential purposes.

More concerning is whether it is wise to create new sprawling tracts of greenfield development in the ecologically sensitive zones along the Estuary, when we should be trying to consolidate new developments on brownfield sites to achieve compact cities. What are the other infrastructure costs required to support such new developments? Why aren't they sited along the Orbital to take advantage of that new piece of infrastructure? Why, if one intention of the vision is to rebalance the economic geography of the country, should it propose so much new construction in the Southeast, instead of marshalling it to the north?

The Orbital

The second component, the Orbital high speed rail line, sets off from the new airport towards the north bend of the M25, the highway that circumnavigates the Greater London region. Yet there is nothing intrinsically preferable about this route, other than that it serves Foster's chosen location for the new airport. Without the Isle of Grain any high speed line connecting the Channel and the Midlands would be routed towards the city centre and/or Heathrow. Therefore there is little synergy between the Orbital and the Estuary airport, that is to say the two projects do not combine to make a whole greater than the sum of its parts.

There is also little obvious engineering synergy in putting the rail line underneath the Thames Barrier as proposed. Given the amount of tunneling the line already requires, if one wanted to run it under the Thames they could be tunnelled anywhere, independently of whether a second barrier was constructed. What seems to remain after these are discounted is the rhetorical synergy of selling the rail line and airport as a two-for-one package.

To reap the full benefit of a new circumferential rail line, it should cater to workers who want to commute along its length as much as to long-distance passengers who use it to access the new airport. This would require the Orbital to be priced as a standard commuter line, not as a premium service like the existing domestic high speed routes between London and the southeast. Foster + Partners state that they are still to model pricing options in detail.

It is funny that with all the other purported advantages cited in the Thames Hub vision, the number of jobs created isn't one of them.

Balancing the regions?

The third component, the national utilities and data corridor, or the 'Spine', naturally follows the routing of the Orbital and the high speed line to the Midlands and the North. As with the Orbital, the routing of the Spine is circumstantial, and its inclusion again does not make for a total vision more than the sum of its parts.

In fact, the idea to economically 'rebalance the regions' in the Midlands and the North runs up against a common problem in regional economic theory. There is a school of thought amongst spatial economists that large transport and infrastructure projects connecting peripheral areas of a continent (like the north of the UK or the south of Italy) to the core areas (like Southeast England or western Germany) often do more harm than good, because of a 'two way street' effect. Transport corridors can draw economic opportunities to peripheral areas, but we forget that they can just as easily draw them to core areas, sucking them out of peripheral areas and rendering the whole enterprise economically counterproductive.

Many economists believe this is exactly what has happened in Europe - that transport corridors planned to achieve regional integration have in fact increased regional inequalities, by consolidating the core of Western Europe to the detriment of the peripheries. There is no reason to believe from the outset that the proposed infrastructure linking the Midlands and the North to London and the continent will be any different.

However at a minor level, there is a synergy in combining the high speed rail line, the utilities and the data networks into a single corridor, since the cost of land acquisition can be reduced by doing so.

The airport

Once the above components have been discounted, we are left with a proposal for an airport that must be evaluated solely on its viability as a location and the feasibility of its construction and resourcing. The strength of the latter is how the vision uses the Thames barrier both to unlock a funding stream and to create a renewable energy supply.

However the location, seen in the context of the six other airports in the region (Heathrow, Gatwick, Stansted, City, Luton and Southend) offers little appeal from a geographic point of view. It requires massive investment in brand new transport infrastructure just to get to the Isle of Grain, whereas the other airports lie on established transport corridors that can be expanded when required. The big three existing sites — Heathrow, Gatwick and Stansted — are all surrounded by sufficient agricultural lands that could be appropriated for expansion. It is only the parochialism of UK politics that has shut down these possibilities.

The Isle of Grain at least offers a palatable alternative to this impasse. And the real advantage this isolated site offers is the possibility of a 24-hour operation. Four parallel runways operating around the clock could allow for 150 million passengers per year, 68% more than the world's current largest, Hartsfield-Jackson in Atlanta, and a huge leap over the total number of passengers in all of London or New York combined. This would knock the socks off London's competitors in the race to be Europe's undisputed aviation hub, such as Paris, Frankfurt, Madrid and Amsterdam (though it could also make it a big white elephant).

The politics

It is funny that with all the other purported advantages cited in the Thames Hub vision, the number of jobs created isn't one of them. The number of residents in Western London who will be spared the environmental impacts of an expanded Heathrow are quantified (five million), but not the number who will be affected in East London and Kent. I can't pretend that the Thames Hub vision was developed according to partisan politics, but it is important that the economic benefits to workers and residents of underprivileged areas be quantified and made comparable to the benefits to corporations and airline customers.

In the end we need people to be thinking on as grand a scale on this, and there is much to be commended in the plans in their current state. But that's not to say that all grand plans are great ones; there is much that should be weeded out, so that we comprehend accurately the intrinsic value of each component as well as the synergies between them. It is a problem that no politician has been able to engineer a movement for expanding one of the existing London airports, but if our politicians have lost the courage for that task, then the Thames Hub airport is one of the better alternatives going.


GU