Issue 536 to

Kings Cross Park, London. Photo by Allison Arieff

Density Within or Growth Outward?

Much like San Francisco, London is grappling with rapid growth.

Urbanist Article

“The people: where will they go?” —Ebenezer Howard, Garden Cities of To-morrow, 1898

London is big, and getting bigger. Greater London’s population is now 8.3 million (incidentally, almost exactly the same population as New York City, which has 8.4 million people).

San Francisco is smaller than London, and even the broader Bay Area, with a population of 7.15 million [1], has a smaller population than the Greater London region’s 13.6 million. Nevertheless, both regions are experiencing a similar dynamic right now: explosive job creation and housing cost escalation.

With the challenge of growth, both London and San Francisco face the same critical question: Where will the people go?

The Economic Miracle of London

London would not be facing this challenge had it not emerged as the most dynamic economy in Europe. Finance still dominates, and in this field, only New York is considered a competitor. London specializes in global investment—the legacy of the British Empire, coupled with a beneficial time-zone placement and a set of advantageous tax laws. It is not only the financial center of Europe, but, arguably, for much of the world. London is also a technology center and it has strengths in a wide range of business sectors from government to media.

London’s population is very diverse — the most recent census reported that nearly one-third of London’s 8.3 million residents were born outside of the U.K.[2] This is the result of years of Commonwealth immigration, coupled more recently by waves of migration from the new Eastern European members of the European Union. At a time when the U.S. seems to be closing itself off to immigration, London has fully embraced cosmopolitanism.

London Population Density per Square Mile
This map illustrates the prevailing policy of focusing new growth at the city center. The densest inner city areas are clustered north of Paddington and near the East End, which are all areas dominated by tower blocks. The City of London and Mayfair are among the least densely populated areas of central London. Map by Andreas Viglakis. Source:

London is experiencing that virtuous cycle in which the gathering together of so much human talent in one place makes a great deal possible. Because many smart people are there, and because the global connections are strong, London is a great place to start businesses. In turn, the more jobs that are created in London, the more it makes sense for ambitious people to move there. London now accounts for more than 20 percent of the entire output of the U.K., and is adding jobs at a fast pace.[3] We see the same thing happening in the Bay Area, of course, and it’s a perfect example of what used to be called “industrial districts,” described famously by British economist Alfred Marshall in 1890:

When an industry has thus chosen a locality for itself, it is likely to stay there long: so great are the advantages which people following the same skilled trade get from near neighbourhood to one another. The mysteries of the trade become no mysteries; but are as it were in the air, and children learn many of them unconsciously. Good work is rightly appreciated, inventions and improvements in machinery, in processes and the general organization of the business have their merits promptly discussed: if one man starts a new idea, it is taken up by others and combined with suggestions of their own; and thus it becomes the source of further new ideas. And presently subsidiary trades grow up in the neighbourhood, supplying it with implements and materials, organizing its traffic, and in many ways conducing to the economy of its material.

This is the classic description of “agglomeration economies,” in which the presence of multiple firms in related industries creates spillovers that positively affect other firms, and it’s the reason that economic growth in places like Silicon Valley or London seems to feed on itself in a self-reinforcing cycle.

For people who remember the London of a generation ago, today’s economic success feels miraculous. Up through the 1970s, the whole of the U.K. conjured images of dying industry, just like the American Rust Belt. Industries were sclerotic. The country was getting poorer. London’s population, which peaked at 8.5 million in 1939, fell to 6.5 million in 1983. Much of this was caused by the decline in manufacturing, similar to job losses in the Bay Area, but it was also part of a deliberate planning policy outlined in the 1944 Greater London Plan by Sir Patrick Abercrombie that called for removing manufacturing jobs from the city, slum clearance programs to clear out the overcrowded inner boroughs, and population and job shifts to new towns beyond the Green Belt.

In the interim, something changed. Jobs came back, and so did people. London’s population is now approaching an historic high, and is projected to rise past 10 million in the 2030s. When SPUR visited London on its annual study trip this past June, I asked everyone in a position to know, how to explain the turnaround. One answer, disconcerting to someone of my political disposition, emerged consistently: Some of Thatcher’s reforms may have worked by restarting the engines of job creation.

Perhaps a global view helps to perceive an even more important pattern: Many, many cities of the “geopolitical north,” including London, San Francisco and New York, lost population after World War II, but then started to regain it. The exact point of the turnaround varies a bit, though the mid-point is around 1980. It’s extraordinary that variations on this same pattern hold for so many different cities: abandonment of the city in the post-war era, followed by a move back to the city that began 35-40 years ago.

That said, the urban renaissance has not been universal. In addition to the cities that started to rebound following decades of decline, another set of cities continued to decline. It appears that this second set of cities is the larger one. These days, when planners talk about “successful” and “unsuccessful” cities, they often mean that as a short hand for adding or losing population — not because it’s intrinsically better to grow, but because it’s an indicator of the health of the economy and the kind of opportunities people feel that they have. People move great distances, even across oceans, for economic opportunity.

For the set of cities that are growing, which very much includes both the urbanized Bay Area and London, planning challenges center on the problems associated with too much growth. In literal and physical terms, we are challenged to accommodate the population growth that comes with new jobs. In social terms, we are challenged to create pathways for all people to benefit from, and participate in, the growing economy.

This shows up most directly for people in the form of housing costs. As more people move to take advantage of job growth, but the housing supply does not grow to keep up with employment, you end up with extremely high housing costs. London is like the Bay Area, but possibly even worse off. The average house price in London is now approaching the equivalent of $770,000.

London’s population is projected to rise past 10 million in the 2030s and it is adding jobs at a dizzying fast pace. The question is whether the city should continue to grow at its center (as with a mixed-use developments like this one on the Thames) or if it should spread outward. Photo by Gabriel Metcalf.

To Grow In — or Grow Out?

In London, the public debate over growth management has taken a specific form. The question is this: Should London increase density within the existing city, or should new towns be built out in the countryside? It’s an age-old debate within the field of city planning that may be instructive for the Bay Area.

London has been struggling with the question of how to manage population growth for a long time. The 19th-century literature of inner-city poverty, from Dickens to Marx, described the evils of crowded slums in London. Generations of reformers dreamed of decongesting the city and moving people out to decent housing in the countryside. One of the founding documents of city planning provides a plan for doing just that: Ebenezer Howard’s Garden Cities of To-morrow, first published in 1898, proposed to create a network of “garden cities” — self-contained towns in the countryside linked together by rail.[4] These towns would allow their inhabitants to enjoy the benefits of both the country and the city — economic opportunity and access to nature, low rents and high wages, community and personal freedom, all in “a carefully planned cluster of towns,” Howard wrote:

…so designed that each dweller in a town of comparatively small population is afforded, by a well-devised system of railways, waterways, and roads, the enjoyment of easy, rapid, and cheap communication with a large aggregate of the population, so that the advantages which a large city presents in the higher forms of corporate life may be within the reach of all, and yet each citizen of what is destined to be the most beautiful city in the world may dwell in a region of pure air and be within a very few minutes’ walk of the country.[5]

Ebenezer Howard went on to organize two new towns, Letchworth and Welwyn, and founded the Town and Country Planning Association in 1899, which continues today as one of the leading planning organizations in the U.K.

Urban Population Change, 1940 to Present (Normalized*)
* Adjusting values measured on different scales to a nationally common scale

The big story here is population loss after World War II, followed by a turnaround. This pattern was repeated in cities all over the world, although the timing, the extent of population loss, and the extent of population turnaround, vary significantly. Source: US census and INSEE (Paris).

Notes: Figure years for London are +1 year; cities are US Census definition of city; Figure years for Paris vary, where more than one year variance, an average of two nearest years was taken.


The Abercrombie Plan of 1944 enshrined the idea of new towns separated from London by a greenbelt as official doctrine. Also known as the Greater London Plan, this document from Sir Patrick Abercrombie observed that London consisted of a set of villages that each had their own centers and, in many cases, were once distinct towns. Abercrombie’s diagram of London is often called the “eggs-in-a-basket diagram.”

The Abercrombie Plan merged this tradition of self-contained villages with the long-standing idea of decongesting central London, and proposed that population growth be directed away from the city into a series of new towns in the countryside. This idea was given a dramatic start by the Luftwaffe’s wartime bombing, which killed over 22,000 residents and damaged 20 percent of the city’s dwellings. Under the auspices of the Abercrombie Plan, more than 30 new towns were built over the next several decades in the greenbelt surrounding London, including Milton- Keynes, with a population of 250,000 people. The New Towns Act of 1946 allowed the government to designate certain areas as new towns, and extensive revisions in 1965 and 1981 were each accompanied by new developments. Meanwhile, London engaged in slum clearance programs under the name of Comprehensive Redevelopment, similar to, and just as devastating as, urban renewal in America.

The Abercrombie Plan
The Greater London Plan of 1944 was developed by Sir Leslie Patrick Abercrombie. Perhaps best known as the eggs-in-the basket diagram, it enshrined the idea of new towns separated from London by a greenbelt as official doctrine.

In speaking about the dilemmas of London’s population growth, the venerable planning theorist and historian Sir Peter Hall (whom, we sadly learned, passed away at the end of the July, weeks after SPUR’s London visit) argued strongly that the right way to manage growth is to create another generation of new towns, out past the greenbelt, or as he put it, “beyond the NIMBY frontier.”

A new generation of British planners questions this orthodoxy. They agree that the greenbelt is sacrosanct and should be protected as open space. However, rather than build new towns beyond the greenbelt, they argue that London’s population growth should be directed to areas within the existing urbanized footprint of London, concentrating the growth near transit. This new generation, which resonates with SPUR’s thinking, celebrates the virtues of walkability and high densities, and notes that the new towns never achieve the level of urban amenity or ecological efficiency of higher-density city life.

In 1998, Prime Minister Tony Blair’s administration invited British architect Sir Richard Rogers to chair an “Urban Task Force” that would define New Labor’s urban agenda.[6] The group published Towards an Urban Renaissance in 1999, which examined the issue of accommodating some four million additional households without further encroaching into the greenbelt.[7] The report became one of the U.K.’s most influential planning documents, and it essentially reversed the direction of Ebenezer Howard, Patrick Abercrombie and Peter Hall by calling for growth to be directed back into London itself. Rogers argued specifically that, “the best form of city is one that is environmentally sustainable, a well-designed compact city organized around transport hubs.” Rogers called for “urban regeneration” rather than spreading outward, both to create good urban places and to protect the countryside.

Ricky Burdett, urban studies professor at the London School of Economics and director of LSE Cities, concurs with this view, and he argues strongly that London’s growth should be accommodated within the existing footprint. As he told us when he spoke to the SPUR delegation, “There is room to fit two Amsterdams inside East London, and that’s what we should do instead of new towns.”

Both Greater London and the Bay Area have produced contemporary blueprints for future growth with the London Plan and Plan Bay Area. The plans discuss the policies needed to address climate change and to reduce the regions’ carbon footprints through promoting sustainable urbanism with more transit-oriented, pedestrian-friendly, mixed-use neighborhoods. Unfortunately, while full of sensible policies, both reports lack compelling illustrations and seem to be intended for bureaucrats and policy wonks. It seems no one has yet produced anything as powerful as Daniel Burnham’s Chicago Plan of 1906, with its beautiful watercolor illustrations; not to mention the fact that it was issued to every schoolchild in the city as part of an effort to create an informed citizenry. Additionally, neither the London Plan nor Plan Bay Area has binding authority over local land use decisions, inside the city or outside of it. They each make an argument about how to manage growth, but they do not have the power to actually stop sprawl from happening.

The growth debate between Peter Hall and Ricky Burdett in some ways mirrors the debate about growth people within the SPUR planning community have heard for years. SPUR has very clearly been on the side of channeling growth into the existing urbanized footprint within walking distance of transit rather than letting it spread into greenfield development at the suburban periphery. Critics of SPUR have argued that San Francisco is “full” and would be destroyed by taking on new growth. It’s not necessarily clear what they think should happen instead.

A third camp has argued that, since it appears SPUR is losing the fight against sprawl, we should devote at least some of our energy toward shaping greenfield development into better — meaning more compact and walkable — formats. New Urbanist planners and designers like Peter Calthorpe have argued that, “planned communities must be judged in contrast to suburban sprawl, not idealized urban environments. For the U.S., new towns are relevant because, though unconsciously, we continue to build them. A housing subdivision, shopping mall, and industrial park with a freeway network is an unmade new town.”[8] It is hard to argue with this.

The Three Magnets
In 1902, Ebenezer Howard published one of the most influential visions in the history of city planning, called Garden Cities of To-morrow. In it, Howard created a series of diagrams that helped to establish the orthodoxy of 20th-century city planning.cooperative socialism.

The British version of this debate differs from ours not just because the Brits believe it’s imperative to reduce driving because of climate change, but because of the existence of a real greenbelt around London and a respectable tradition of building new towns that are actually walkable and linked by rail. In other words, new towns in the U.K. are likely to be far better than suburbs in America.

Nevertheless, it’s striking how similar, and how perpetual, this debate is: to grow out, or to grow in? In 1941, SPUR (then the San Francisco Planning and Housing Association) worked with the modernist planning group Telesis to produce a report and exhibit, “Planning for the Next Million People,” which intended to show regular citizens all the regional activities they engaged in during their daily lives, and connect that to the need for regional planning. Anticipating the calls of Bay Area environmentalists and progressive planners in the postwar period, Telesis argued that a regional planning agency was the only true solution for planning urban growth, preserving greenbelts and solving regional transportation issues.[9]

We’ve been having this debate for a long time.


Letchworth, established in 1903, was the first garden city and had great influence on future town planning and the New Towns movement.

The Limits of Planning

The first generation of planners in America believed that planning should not just deal with land use and transportation (as it mostly turned out to do), but should also have powers over the economy. They were not necessarily all socialists, although many had sympathies in that direction; rather, they believed in the growing powers of human intelligence and science, and the growing ability of people to rationally organize their affairs. Planning was considered by some to be a “fourth branch” of government, separate from the legislative, executive, and judicial branches, the one branch that would be apolitical and objective. The New Deal, certainly, was an expression of this worldview, and it represented an attempt to use the planning of many realms of the economy that had previously been left to the private market.

In the Bay Area, this included people like Mel Scott, Fran Violich and T.J. Kent, some of whom met each other while working on farmworker housing in the Central Valley during the New Deal. On the national stage, the leading thinker was Lewis Mumford, who expressed the optimism of the time about being able to rationally locate economic activity to where it made the most sense. In Technics and Civilization (1934), he celebrated the “neotechnic” possibilities of the coming age:

Moreover, the neotechnic distribution of power makes for economic regionalism: the concentration of population in the coal towns and the port towns was a mark of haphazardly organized labor supply and of the high cost of coal transportation. One of the large possibilities for economy lies here in the abolition of cross-hauls: the familiar process of carrying coals to Newcastle. Traders and middlemen gain by lengthening the distance in space and time between the producer and the ultimate consumer. Under a regionally planned distribution of industry, this parasitism in transit would be reduced to a minimum. And as the knowledge of modern technics spreads, the special advantages in skill and organization and science, once enjoyed by a few countries alone, by England during the nineteenth century above all, tend to become the common property of mankind.

That generation of planners dreamed of being able to rationally locate economic activity to the benefit of underdeveloped regions and to optimize natural resource efficiency.

But what ended up emerging was an economy that is largely beyond the scope of the tools of planning. Jobs are created wherever firms can make profits by hiring people; conversely, jobs disappear where firms don’t make profits. Investment in a now fully globalized economy moves to the locations that generate the highest returns. No one in government gets to make the fundamental locational decisions of our economy, except indirectly through the provision of infrastructure to certain locations and the setting of tax policy. The outcomes in terms of economic geography — which places grow, and which contract — emerge, rather, from the atomized decisions of thousands (millions) of consumers, investors, and business managers.

People often ask, “Wouldn’t it be nice to move some of London’s economic activity to the struggling industrial towns up north like Manchester or Leeds?” or, “Wouldn’t it be nice to move some of Silicon Valley’s dynamism to Fresno, or to Detroit?” Yes, it would. But it’s highly unlikely. We simply don’t possess the tools to make those moves happen.

The convergence of talent, anchor institutions and business cultures into successful economic clusters is a rare and special occurrence. The government does not have the power to separate off pieces of a cluster and move them where we wish they would go. Indeed, no entity does.

One way to allow more people to experience personal prosperity is to help them participate in the economies that have this special alchemy. This is a literal, physical question — can people freely move to economically strong regions, or are there exclusionary barriers to immigration? But it is also a question of culture and class: Many people who live within commuting distance of good jobs are still not in a position to get them. The barriers are wide-ranging: lack of education, lack of connections, cultural capital and/or racism.

At SPUR, as we work to deepen our thinking about economic inequality and what to do about it, these days we are focused more on the “human” side of the problem, much more than the “place” side of the problem — in other words, giving people the skills and connections to be able to get better jobs, rather than hoping that physical improvements to neighborhoods will bring prosperity on their own. In places with shrinking economies, there simply are not enough jobs for the people who need them. Efforts to address economic inequality face an enormous uphill battle in these locations. And here, you will see civic leaders extremely focused on attracting and retaining “talent” rather than letting it all move to the regions with stronger economies.[10] In places like the Bay Area and London, where jobs in many different sectors of the economy are growing, it should be easier. Here, we should at least have a fighting chance to do something meaningful about economic opportunity by connecting more people to the economic opportunity that exists.

When we look at London, it’s almost like seeing a bigger, magnified version of ourselves: more job growth, more immigration, more pressures on development, more economic inequality. We’re both coping with the pressures of too much growth. Those problems are still probably better than the pressures of not enough growth.



[1] MTC Bay Area Census data

[2] “Londoners born overseas, their age and year of arrival,” Census Information Scheme. Pg. 3.…

[3] “Jobs and Growth Plan for London,”…

[4] Howard’s book was first published in 1898 as To-morrow: A Peaceful Path to Real Reform. It was republished in 1902 as Garden Cities of To-morrow.

[5] “Quoted in Hall and Ward, Sociable Cities, p. 23.

[6] Richard Rogers became closely associated with New Labour while they were in Opposition before the General Election of 1997. The Shadow Cabinet used to meet every week at the River Café, run by Rogers’ wife Ruth, and located on the ground floor of Rogers’ office in Hammersmith, west London. Rogers would invite them up to the office to discuss the need for planning and design, and this led to his being put in charge of the Urban Task Force and being nominated to the House of Lords to become Lord Rogers of Riverside.

[7] Towards an Urban Renaissance

[8] Peter Calthorpe, “A Short History of Twentieth Century New Towns,” In Sim Van der Ryn and Peter Calthorpe, Sustainable Communities: A New Design Synthesis for Cities, Suburbs, and Towns, Sierra Club Books, 1986

[9] “Progress Intentionally Planned,” by Peter Allen, The Urbanist, July 1, 2009

[10] For example, Richard Florida, The Rise of the Creative Class (2002), or Joseph Cortwright’s work for CEOs for Cities, “The Young and the Restless in the Knowledge Economy,” (2005),

Gabriel Metcalf is SPUR’s Executive Director.

Special thanks to Flavio Coppola, John Ellis and Mike Tietz.