The Global Urbanist

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The knowledge gap dividing the two halves of the World Urban Forum in Medellín

Reviewing UN-Habitat’s World Urban Forum held in Colombia’s star city last week, Laura Cesafsky hears two camps talking past each other on the lack of scientific knowledge underpinning the New Urban Agenda, suggesting that much research must be done if we hope to put sustainable cities at the centre of the Post-2015 Development Agenda.

Laura Cesafsky

Laura Cesafsky

Cities: Medellin

Topics: Integrated planning, The global urban agenda, The road to Habitat III

“We want to prove that urbanisation is a transformative force.”

It was another flawless, sunny afternoon in Medellín, Colombia, the “City of Eternal Spring”, but 75 of the world’s urbanists were huddled indoors under fans listening to Eduardo López Moreno, director of research and capacity development at UN-Habitat. It was the second day of the World Urban Forum, the organisation’s biannual fête, and Moreno was outlining his take on the afternoon’s theme: urbanisation and the spatial development of cities.

Wait, we don’t know this, that urbanisation is a transformative force?

It struck me as an odd admission. After all, a record 22,000 attendees were arriving in Medellín from all over the world to discuss this suddenly nebulous phenomenon.  The world’s urban population is expected to increase from 3.5 billion in 2010 to 6.2 billion in 2050, and almost all of this growth will happen in developing-world cities.  We will somehow have to accommodate these new urbanites, not to mention all those already urbanised. We will have to provide them with services, jobs and a decent standard of living, and we will have to do so without trashing the planet. Isn’t urbanisation already transforming everything, transforming the entire playing field of sustainable development? Did we not know this?

Do we know or not?

Over the course of the week such outpourings of uncertainty would prove commonplace, de rigueur. They came largely from representatives of the most important organisations: the World Bank, the UN, and the development banks. Somik Lall, senior economist with the spatial and local development team at the World Bank, would say it multiple times, in multiple settings: we know almost nothing about urbanisation and the spatial development of cities. We do not know what determines urban form—the way the physical spaces, objects and boundaries of the city are laid out. And we do not know, not really, what form determines. We don’t know how spatial interventions work to create the sustainable, equitable, and inclusive cities we want. The theme of the conference was “urban equity in development—cities for life”, but we could not prove what a “city for life” was or how to build one. What we needed, experts agreed, was a science, an urbanisation science.

Only one idea was repeated more often. That was that we did know, we do know. People who did not work at the World Bank, the UN, or the development banks were most likely to express this sentiment. As the ebullient urbanist Richard Florida opined to the equally ebullient planner Brent Toderian in their keynote conversation, urbanism is the rare field with broad consensus around its key principles. It’s all about the compact city: dense, mixed-use development oriented around transit, public space, and other public goods. This is how we create the environmentally friendly, socially inclusive, and economically dynamic cities we want. The problem is not a deficit of knowledge, but rather a deficit of political will. Medellín had the political will to transform collective life by transforming its built environment. That was why we were all here.

There was little debate or conflict at the Forum. There was only the vague dissonance created by these two incompatible discourses scraping past one another. We are at a critical moment when the compact city is central to achieving sustainability, equity and inclusion. Yet we know little about how the spatiality of the city produces this sustainability, equity and inclusion.

Wishful thinking or science?

Right outside One UN Room, the auditorium where Moreno was warning that we are still far from “proving that the integration of land uses benefits a city,” WUF organisers set up a huge storyboard, over 3m high and 20m long. It flanked the main entrance of the large exhibition hall, the first and last thing visitors saw. With beautiful illustrations and simple text, it told the story of the last 60 years of urbanism. It was a story of form. First, the definitive monstrosities of the Modern era were trotted out one by one: debris-strewn Corbusian “towers in the park”; “metastatic cities” of sprawl, their tiny developments dotted like pimples at distances from the urban core; the city of monofunctional zoning, its single-use regions connected only by sinuous highways. At the end of the story was a single heroic conclusion: the dense city of land-use integration. This was an inclusive city that, the storyboard read, “promotes social cohesion, engagement, job growth, reduced automobile dependence, more walking and cycling, and a strengthened sense of community, civic responsibility and safety.”

Are today’s urbanists no better than the Modernists, artists rather than scientists, who order cities according to aesthetic and representational logics? Are we simply hoping that compact cities will save us? Or worse, assuming?

Not exactly. The new urbanisation science that the development organisations want is coming. There were signs of it all over at the Forum. And in the moments when conference panellists directly confronted the dissonance between the two discourses, between the knowing and the not knowing, this science’s contours, raison d’être, and limitations emerged. We have had many urban sciences in the past, but this one is different. It is a science that tracks and monitors urbanisation processes across the world, comparatively, so that we might more effectively intervene in them. Rather than explore new possibilities—new forms—its central objective seems to be to show that the spatial interventions we are already making really do the things we hope they will. We want to prove that compact, mixed-use development is inclusive, equitable and sustainable.

The urban form of the Post-2015 Agenda

Why is this urbanisation science important, and why is it so focused on form? The easy answer is that the built environment is at the centre of UN-Habitat’s mission, and it’s their conference. But there are other answers, too. One is that we are in the final dash to Habitat III in 2016. Habitat III is the real urban conference. It meets only once every 20 years, and it is where the major players meet behind closed doors to actually set the urban agenda. The urban agenda, and really the question of space overall, has been an afterthought to the UN’s sustainable development agenda, which is also getting a post-2015 overhaul. UN-Habitat wants to push the urban agenda from the margins to the centre of the sustainable development agenda. On an urbanising planet whose built environment must be entirely transformed, there is a never-ending list of concrete, tangible, potentially fundable urban infrastructure projects. But getting these to the centre of the development agenda and getting them funded will take more than illustrated storyboards, as Lall and other experts repeated. Some facts linking particular urban spatial developments to particular economic, social and environmental achievements were going to be necessary.

Second, the very objectivity and visibility of the built environment makes it a uniquely powerful development indicator. Using new high-resolution imaging and algorithmic technologies, the Europe Union Joint Research Centre’s Global Human Settlement Layer and several other ongoing projects are now monitoring and analysing human settlement forms from space. The hope is not just to understand current and historical urban expansion, but also to inform planning and development policy and to evaluate new spatial interventions. The central conceit is ambitious: that we will, someday soon, be able to draw conclusions about socioeconomic dynamics and living standards from the alignments of buildings, streets and open spaces in urban settlements. Qualitative depth might be lost with such methods, but they circumvent national governments, their political whims, and their faulty and inconsistent social data collection methodologies.

Finally, and perhaps most importantly, form is central to the new urbanisation science because it expresses urbanism’s secret weapon, its ace in the hole: the inherent power of density itself. Density is “the city’s DNA”, as Florida put it at the Forum. In today’s echo chamber of bad news—growing socioeconomic inequality, rising sea levels, vicious cycles, unintended consequences—wouldn’t it be incredible if this thing that was going to happen anyway, this clustering of the population into cities, turned out to be innately positive for people, the economy, and the planet?

Getting down to details

It’s an exciting time to be an urbanist because we've collectively decided, much in contrast to modernist urban thought, that our object of inquiry is basically good. This is the true meaning of Moreno’s utterance that “we want to prove that urbanisation is a transformative force.”  The ultimate ambition of urbanisation science is not to show that urbanisation is relevant. Obviously it is. It is to somehow prove that urbanisation is transformative in the normative sense, to show that density, like biodiversity, is a natural gift around which sustainable development ought orient itself.

As ever, the devil is in the details. How dense, for example, is the optimum density? Debates around greenbelts, a much-publicised density technology as made famous by Ottawa or London, well illustrate the problem. But host city Medellín is currently working on its own spectacularly ambitious, 75-kilometre version that will double as a huge park for the poor in the mountainside neighbourhoods ringing Medellín. The cost of the project: more than $275bn. But as NYU’s Shlomo Angel has been emphasising for years via his Urban Expansion project, which was heavily publicised at the Forum, containment might be an unrealistic strategy for rapidly growing cities. It can raise land values to exorbitant heights. So where are greenbelts appropriate, and where will they make cities too dense for equality’s sake? We do not know.

Despite such lingering questions, we have much better science at the nexus of urban form and the environment nexus than we do at the nexus of urban form and society. The Global Commission on the Economy and Climate’s New Climate Economy (NCE) project, whose cities research is co-directed by LSE Cities’ Philipp Rode, is well on its way toward assembling authoritative evidence on the relationship between big-picture infrastructure and spatial development, economic performance and climate mitigation. The ultimate objective of the project, as Rode explained in one WUF session, is a definitive list, written for urban policymakers, of urban infrastructural interventions that are scientifically proven win-wins for economy and climate.

Yet as Edgar Pieterse, director of the African Centre for Cities, pointed out to Rode after his presentation, the NCE project says absolutely nothing of the social. Rode’s response: poverty and inclusion are not yet “operationalisable,” but there is “probably almost a 100% overlap” between climate interventions and equality interventions. This is a significant problem for urbanisation science. Yet we have known about it for some time. The planner Kevin Lynch noted already in his classic 1984 text Good City Form that values like social integration and strong communities are only “weakly linked” to urban form, and that anyway they are difficult to detect or measure. There are plenty of design elements that we think have positive social effects—creating infrastructural connections across urban space, building public spaces—but how can we tell that these interventions are working? Without an easily measurable currency, as carbon is for climate change, it is difficult to make the effects of “inclusive” spatial interventions scientifically legible.

Where do we shine the spotlight?

Thus a great irony of this seventh World Urban Forum. We were all in Medellín to celebrate a much-lauded urban transformation, from “murder capital” to inclusive metropolis. Yet the reality of this transformation, so evident to many visitors and residents, is scientifically uncertain. Medellín’s innovations include a focus on pedagogy, on public participation in the planning process, and on civic culture, but the spotlight has shone overwhelmingly on its iconic and photo-friendly built-environment transformations: the high-design libraries and schools that are physical statements of support for previously neglected areas; the sleek metro system, cable cars and escalators that reduce commute times and integrate poor neighbourhoods previously cut off by the city’s mountains. All these projects come swaddled in heavy discourses of equality and inclusion. But what they have actually done is largely unmeasured, and perhaps immeasurable, a story rather than a statistic.

Strangely, the most important structural element in Medellín’s transformation is the least lauded: the unique charter of its utility company, Empresas Publicas de Medellín (EPM). EPM is owned by the city. But it operates as a private company that passes roughly 30% of its annual profits back to city for social investment projects. Unlike most cash-strapped developing world cities, then, Medellín can experiment. It can spend $7m on a single outdoor escalator system in a single comuna. But as the new urban agenda of green and inclusive cities moves forward—rich in promises and lockstep in vision, yet poor in data and deficient in funds—few cities will share Medellín’s key luxury: to simply build. Perhaps what Medellín shows more than anything is that inspired urbanism is half art, half science. But what development bank will fund art in the urban age?


Laura Cesafsky is a PhD candidate in Geography, Environment and Society at the University of Minnesota. Her dissertation focuses on the long-term impacts and achievements of Bogotá's famed bus rapid transit and bicycle systems, and on that city's experience as a previous global "urban model".

Also today, Kerwin Datu and Naik Lashermes writing on behalf of The Global Urbanist's editorial board call attention to what the Habitat III Agenda fails to consider, and put forward our own vision of a truly new Habitat III Agenda: an end to discriminatory development.

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