Category Archives: Science

Growth. Are you old school or new school?

There are two different schools of thought about how to accommodate urban growth. The first says that cities should build more road capacity to handle private vehicle traffic. The second says that less space should be provided for private vehicles and more investment should be made in public transport and “active travel” i.e. walking and cycling. The first approach is generally more costly than the second.

The old school of thought has prevailed for around a century. The new school is relatively more recent, responding to the frequent failure of the former, where more road space has created more road traffic, which has created more congestion.

Cities all over the world are now removing expensive car-oriented infrastructure and introducing space for walking, cycling and public transport. Ring roads and bypasses are being unpicked and cities are thriving as a result. Look at Copenhagen, Paris, London, Birmingham, Boston, Poynton or any number of places that have employed the new school approach.

On Poynton…”This was the busiest junction in Cheshire, with 25,000 vehicle movements per day and the fourth worst performing retail centre in Cheshire East. It now accommodates a similar volume of traffic, but since average speeds have fallen to below 20mph, drive times through the centre are significantly reduced. Anecdotally people feel safer crossing the carriageway and cars will stop for them, make eye-contact and usually elicit a wave of thanks from the pedestrian.” The Academy of Urbanism

Road speeds are being reduced, from 40 or 50mph to 20 or 30mph. Not only on residential streets but at the intersections of major roads too. Why? Because when you slow traffic down it flows more freely. Why? Because at lower speeds, more vehicles can fit into the same space. This isn’t rocket science. It’s simply a different school of thought.

When a city pursues “old school thinking” of road capacity increases and banned turns then not only is this going to generate more road traffic it is also going to make it ever harder for people to do anything other than drive. In these circumstances, walking and cycling become harder. “Walking and cycling facilities” might be put in but these are often token gestures because they are fitted in around the needs of traffic. Desire lines – the paths that people prefer to take – are severed and people are encouraged to walk or cycle on unnaturally twisted journeys. What happens as a result? They don’t use these “facilities” and they take risky alternatives, dashing across road lanes or cycling among fast-moving traffic.

Old school thinking is voracious – once started it is hard to stop. Nevertheless, evidence, analysis and creative thinking can help. If there is a willingness to listen.

I speak from the perspective of practice – of having observed the behaviour of people on foot, on bikes and in vehicles in a scientific manner for over 25 years. Of having presented evidence of fact to local authorities and of overturning poorly thought-through, old school proposals. Of having designed alternatives that don’t put anyone in particular first but instead balance the needs of all. This isn’t about being pro-bike and anti-car. It’s about being pro-place and pro-cities.

And let’s be clear, new school thinking is fundamentally about being pro-growth. But pro a form of growth that is smart and sustainable: growth that doesn’t sacrifice the profound benefits of local places for the expedience of cross-city commuting, but growth that promotes alternative ways of traveling and enhances the attractiveness of cities as places to live in and invest in.

We are what we street. The elements of successful #urban placemaking

PART ONE – THE ELEMENTS OF SUCCESSFUL URBAN PLACEMAKING
Location
How the site fits into its context, including complementary and competitive attractions; in other words, what else is nearby to which the design should respond? The success of any development, no matter how large, is a function of the wider setting.

Linkage
The specific points at which connections can be made into this context, including public transport connections; in other words the “gateways” into the design.

Layout
The spatial layout design of the project itself in terms of its streets and spaces, whether public/private or open/covered, and the importance of:

– first, encouraging through movement connections between gateways

– second, providing a simple, intelligible internal circulation network through a grid of streets and other connections.

This is the most important of the five elements since the spatial layout, once created, tends to be the most permanent part of the development. It is the most expensive to alter once constructed since it sets out the footprints of buildings and, importantly, since it carries the bulk of major services such as energy, water and data supply as well as waste handling.

Land use
The quantum of different land use attractions and the disposition of these within the spatial layout both in two and three dimensions; in other words where uses are and how they stack up, especially the land uses that occur at street level and any other principal pedestrian levels.

The location of land uses should follow the hierarchy of spatial connections created by the spatial layout design, with the most movement-sensitive land uses located on the most spatially important connections and so on. This alignment of land use attraction with spatial layout attraction is a fundamental property of both historic cities and successful modern places.

Landscape
How the spatial layout is “dressed” both in terms of the “green/blue” landscape of planting and water and the “architectural” landscape of building frontages at the principal pedestrian levels.

Here what matters is that the spatial layout is not overly fragmented or dispersed by planting and that the principal pedestrian levels are lined with open, active frontages.

PART TWO – THE DESIGN
The five elements of successful placemaking establish a framework for design practice. What matters next is the way in which these generic principles are translated into a specific design proposal. This is a creative step, which relies on a blend of imagination and craft, honed by experience.

The challenge for future urban practice is that the five elements are not commonly appreciated in the field of retail development, which has instead adopted principles of gravitational attraction that tend to create anchored, inward-facing, covered malls rather than open, street-based shopping streets, whether we call such streets “high streets” or “souqs”.

PART THREE – THE WAY FORWARD
It has been, and will continue to be, down to pioneering organisations to point out what is increasingly obvious to all but those who are too immersed in it: that anchored malls create sterile places; and then for these pioneers to deliver new places that work because they employ the timeless elements of successful placemaking.

Fortunately, this challenge is facilitated by the continued emergence of technology-based tools for analysing location, identifying points of linkage, testing different layout concepts and modelling the interaction of these with different land use and landscape treatments.

We don’t guess the structural performance of individual buildings so why do we guess the human performance of entire cities?

The structural steelwork of a large and complex building would not be designed without running engineering calculations. Even the smallest of buildings is subject to objective structural analysis. No client and professional team would rely on guesswork, no matter how famous or experienced the architect or engineer.

So why do we leave the human performance of places to the whim of architects who run no calculations and rely only on their instinct and ego? Why is the science of human behaviour so poorly developed? Why is chronic failure still tolerated?

In the early sixteenth century, William Harvey challenged the medical profession to take a more objective, more observation-driven approach to the understanding of the circulation of blood. At the time, medical thinking was largely based on the beliefs of Galen of Pergamon, who had set these out in the second century. Harvey challenged a medical mindset that hadn’t changed in one and a half millennia. And he encouraged his peers to embrace advances in science that allowed new forms of investigation.

We can see a similar state of affairs in the prevalence of, and institutional inertia around, twentieth century planning. Based on belief, not observation-based science, a doctrinal approach to urban planning and design pervades the professions. This is the case, whether the specific approach is Modernism, the Garden City movement or (and especially) Landscape Urbanism. Each is to some degree unscientific.

These approaches propose different kinds of urban outcomes but what unites them is a belief that the future should look fundamentally different to the form of continuously connected, dense and mixed-use urbanism found in cities for as long as there have been cities – the kind of urbanism that architects and town planners visit on their holidays.

The kind of urbanism – and here’s the irony – that Galen would have recognised. If only architecture and town planning were stuck in a fifteen hundred-year-old mindset. We would still have vehicles on the road but we wouldn’t have vehicle dominance. We wouldn’t have land use zoning that generates long-distance commuting, traffic congestion and negative health impacts. We wouldn’t be encroaching on the rural landscape with semi-detached, density-fearing dwellings.

Fundamental change in our professions is needed and science has an important part to play. In the spirit of Harvey’s observation-based approach, we need to embrace the new capabilities offered by sensing, analytics and modelling. We need to understand how cities truly work before we then form ideas about how to change them. We must move beyond the beliefs of twentieth century practice. The evidence is there to demonstrate that practice based on belief hasn’t delivered great places with the consistency required either by the investors in them or the users of them.

We can learn from Harvey, even if our end goal is the urbanism of Galen.

Sustainability & resilience – a SMART approach

1. Aspects of sustainability/resilience: SMART outcomes
Social – improvements in formation & retention of social connections

Environmental – increases in renewable energy production and reductions in energy demand

Economic – increases in land value creation

Health – improvements in public health outcomes

Education – improvements in achievements/qualifications

Safety – reductions in offending & reoffending.

Environmental
Urban carbon footprint is made up of:
1. Building carbon.
2. Transport carbon.

Urban carbon reduction can be achieved by:
1. Building carbon reduction – intelligent building services: heating/cooling, lighting.
2. Transport carbon reduction – walking, cycling, public transport & less private vehicle use.

2. Process specification: SMART inputs
1. Integrated Urban Modelling of existing building performance and transport performance.
2. Predictive Urban Modelling of expected development impacts.

3. Asset requirements for SMART approach
1. Pervasive data sensing
2. Data mapping – centrally coordinated & then distributed eg open platform distribution
3. Data analysis – undertaken by city, academia & industry then shared
4. Planning & design response – use of data to create development proposals
5. Development proposal testing – using the Integrated Urban Model.

Sustainable cities of the future – sketch

Notes for keynote at UK Green Building Council Annual City Summit, Birmingham.

1. Spatial planning & human behaviour implications of sustainability – reduction of transport carbon through shift towards walking, cycling & public transport

2. A massive shift needed in transport + land use planning, urban + landscape design, architecture. Professional inertia. Turning the supertanker.

3. A massive opportunity. Reason to turn.

4. Lessons from the past eg Pompeii, Brindley Place.

5. Examples from the present eg Darwin, London SkyCycle, Birmingham Charette.

6. UK government: Smart & Future cities agenda is a sustainability agenda.

7. Social inequalities dimension of sustainability.

8. Need to act at all scales simultaneously ie there’s work for all of us to do.

9. Challenge for modelling.

10. Challenge for research.

11. Challenge for practice: design, development & real estate investment.

12. Already being acted on. The supertanker is turning.

Permeability & connectivity: a tale of two cities

Notes from a response to questions from the Strelka Institute. 

How would you describe the situation with the permeability and connectivity of city spaces today?

There is no single state of permeability and connectivity in the contemporary city. Instead we find two main types of urban layout: first, the finely grained, continuously connected street network in the historic city and second, the system of largely impermeable housing estates separated by fast-moving roads in the 20th century city.

In the historic city, space is well used. Most space use is movement and most movement is through movement. Movement supports commercial activities, which locate themselves on the principal streets where footfall is greatest. Movement brings people to places of opportunity – to buy, sell, exchange and interact. Effective exchange and interaction drives urban economies, social networks, cultures and innovations.

In the 20th century city, the large, impermeable blocks of the housing estates do not encourage through movement. People move around the estates rather than through them. As a result, commercial activity is undermined, with its market divided between people moving locally inside the estate and those moving globally around it. Commercial activities are more likely to fail, especially inside estates where the marketplace is too weak. Instead, shops form at the entrances to the estates and on the surrounding roads. Since these roads have often been designed to favour the car, the shops are likely to be car-based, with large parking lots that further separate local people from them.

A further, social consequence of this is that local people do not see people from outside the estate on the regular basis that people in traditional streets take for granted. The effect of this is to create social isolation and fear of strangers in estates.
The irony is that the inward-looking urban block was created purposefully to foster a stronger community spirit. Traditional streets were considered to be noisy, dirty and dangerous. 20th century town planning’s idea was that, if life could be created away from streets then people would be cleaner, happier and safer.

It is the greatest tragedy of 20th century international planning that its well-intended model of urban living has failed. Indeed it has done the opposite: creating highly negative social and economic outcomes for all people with perhaps the exception of the super rich for whom social and economic relations are formed in different spatial contexts.

Connectivity is closely connected with the structure of property ownership, how will it change in the next 5 years? Will it shift towards privatisation of public spaces? And what will be the case 20 years from now?

Undoubtedly the next decade will see more private spaces set within gated communities. Such forms of urbanism are still favoured by developers and aspirational residents for whom the idea of living in a cleaner and supposedly safer environment is expected to make them happier. The history of 20th century failure may not be considered to be relevant, perhaps because of a belief that it happened somewhere else, or in a different socio-political era, or because new digital communications technologies can effectively span the spatial divide between such places and their urban settings.

At the same time, the resurgence of traditional street design will see more places created that look more like the continuously connected form of the historic city. This trend can be seen in cities as diverse as Beijing, London and Dubai, where permeable street networks have been created by commercial property developers as well as public municipalities precisely because they are seen to deliver places that are popular with people. The social and economic benefits of a street-based approach have been witnessed with a combination of satisfaction and surprise.

Perhaps the most significant impact on the form of urbanism in the future city will come from the digital technologies that will record and analyse the outcomes of both approaches – the gated community and the open street network – and demonstrate with evidence how each performs.

My clear view is that the continuously connected street network will outperform the gated community in terms of Urban GVA, making a greater contribution to the overall social and economic value of the city. The emerging Science of Cities, in which my company Space Syntax has been a pioneer, is one of the key areas of future urban practice that will cut through the inaccurate claims that have been made about the benefits of estates – claims that have been promoted by architects and urban planners throughout the 20th century, based on the passion of their beliefs rather than on the evidence of facts. Urban analytics will transform urban practice over the next 20 years, shaping a new, evidence-rich approach to architecture and town planning and, crucially, returning a highly effective, street-based form of urbanism to the position it had held for centuries before professionalised town planning imagined it could do better.

During our work for the classification of Moscow streets we highlighted three different zones of the city: centre (inside the Garden Ring), middle zone (between the Garden and the Third Transport Rings), and periphery (outside the Third Ring). The pattern is completely different in these zones. Could you comment on the implication of global trends of connectivity in the city on different zones in Moscow?

No city is the same from its centre to its edge. Or, more precisely, from its centres to the edges of those centres because cities are formed of multiple centres that create a system of connected urban quarters. The quality of the connections between centres is a fundamental determinant of overall urban performance, having a strong bearing on whether people are more likely to walk and cycle between neighbourhoods and whether those links will be effective places for social and economic activity. When centres are continuously connected to each other through a set of connections with a regular grain then it is likely that many, if not all of these will be suitable for walking and cycling as well as driving along.

Cities like London and Paris are composed of multiple centres that have distinct centres of differing characters yet are continuously connected to each other. Indeed it is the magic of such cities that it is possible to move from one centre to the other in such a subtle way that you are uncertain exactly when you have left one centre and entered another. The connective “tissue” between centres is typically comprised of residential streets, which therefore link to – and carry movement belonging to – multiple centres. People may identify more with one centre than others but they are provided with a choice of more than one. And,min doing so, they interface with people from more than one centre. The benefits of this arrangement are simultaneously social and economic.

Such choice is denied by the 20th century city of separated estates. People living in one estate have limited, if any direct access to the centres of other estates. Increasingly, the roads that connect between estates are hostile to pedestrians and cyclists. Social and economic life is suppressed.

All cities are systems of linked centres that each work in individualistic, local ways but that also form an overall city system. Within this city system, the centres have a hierarchy with more central centres typically supporting greater economic activity than centres at the edge. This is not only because more central centres are larger but also because these centres are surrounded by a larger number of other centres than are peripheral centres.

In the case of Moscow, Space Syntax analysis would be used to examine the hierarchy of centres, the quality of the connections between them and the degree to which spatial connectivity is directly related to social and economic performance. Data on economic performance – such as land value, property transactions, commercial performance, retail sales – would be correlated with measures of spatial connectivity – such as spatial centrality (choice) and betweenness (integration) at a range of spatial scales. These Big Data sets would be interrogated in order to form a diagnosis of the current spatial conditions. On the basis of this diagnosis, a set of spatial planning principles would be created that would lead to the production of a spatial vision for the city. We anticipate that this form of data-rich, evidence-informed planning will become normal in the next 20 years.

While improving and redeveloping city streetscape how should trends in the connectivity and permeability of city space be taken into account? 

Space Syntax analysis shows how patterns of spatial connectivity have profound influences on the social and economic performance of all cities. The hierarchy of spatial connections influences:
movement patterns of cars, cycles and pedestrians

– public transit demand

– land use performance

– land value

– transport emissions.

Future urban plans should therefore be created with a special emphasis on the design of the spatial layout of the city. Opportunities should be identified to strengthen the network of streets and open spaces, pursuing an overall objective to create a city of continuously connected centres. Constraints should equally be identified so that reasonable plans can be made.

“Spatial geometry” standards should be set for the number and frequency of connections as well as for the geometrical means by which centres can be most effectively connected ie first, a small set of longer, more direct connections (the “foreground grid” of boulevards and high streets) that will carry larger volumes of people and therefore be suitable for commercial uses and second, a large set of smaller, less direct connections (the “background grid” of local streets) that will carry smaller volumes of principally residential movement.

Once these spatial geometry standards have been established then further standards of urban design quality should be set – but not before. High quality urban design in the form of green landscape, seating, signage me surface treatment will not create high quality urban performance if the spatial layout geometry is weak.

The living city is built on human interaction. Without this, the city is dead. Human interaction relies on effective movement corridors and effective places of human transaction. Effective street connectivity is a critical determinant of the living city.

Integrated Urban Planning – balancing the multiple flows of the city

Notes for the UK-China Sustainable Urbanisation Conference in Chengdu, China on 24th September 2015

  

My job as an architect and urban planner is to design new towns and cities – as well as new parts of existing urban settlements. This means designing the multiple systems that make up a city. We often think about towns and cities in terms of their physical stuff: their buildings. Perhaps also in terms of their roads and rails. But for me the success of any city can be seen and measured in terms of its flows, the flows of:

  • energy
  • water
  • data

and, most important of all, the flows of:

  • people: in cars, on public transport, on bicycles and on foot.

Each of these flows is impacted by urban development: how much of which land uses are placed where, and how they are then connected to each other. Flows impact on other flows.

Sometimes these impacts are positive, sometimes negative. They have enormous social and economic implications.

Urban planning is as much about designing flows as it is designing buildings.

We live in an age of unprecedented computing power – this gives us the ability to better predict the nature of these impacts.

This is especially important to avoid the unwanted effects of urban development: congestion, air pollution, social isolation and unsustainable stresses on natural resources.

And computing can help create the positive impacts that are needed to support the essential purpose of cities: to be:

  • machines for human interaction
  • crucibles of invention
  • factories for cultural creation.

The last decade has seen the emergence of Integrated Urban Modelling. My company, Space Syntax, is a leader in the field: one of the UK companies referred to by the Chancellor as contributing to China’s growth and development. Working, for example, with the China Academy of Urban Planning and Design across China in Suzhou and Beijing.

Integrated Urban Models link the data generated by the multiple flows and reveal the interactions that help architects and urban planners create sustainable plans. Space Syntax has identified the essential role of spatial layout as the principal influence on urban performance. Spatial analytics are at the heart of our approach to Integrated Urban Modelling and we have made our discovery open source and openly available so that others can benefit too.

The Space Syntax Online Training Platform is a freely available, web-based resource through which urban practitioners, policymakers and local residents can equip themselves with information and skills to create more sustainable urban futures.

I’m pleased to announce that this platform is currently being translated into Chinese so that the Space Syntax’s discoveries and experiences can be more readily disseminated here in China.
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Integration, balance, glue, pivot: space
In many ways, urban planning is the integration and balancing of multiple flows. Integration needs glue and balance needs a pivot. Spatial layout provides both.