Do Not Define Urban Design too Narrowly

Jonathan Barnett

Urban Design Consultant and Professor Emeritus at the University of Pennsylvania

Matthew Carmona’s thoughtful essay defining Urban Design as a place-making continuum seeks to create a more consistent basis of theory to guide both future urban designs and evaluations of built environments. Objective analysis of what urban design is, and how it works, is clearly valuable; and professor Carmona’s research into public places in London sets a high standard. The question is

whether as professor Carmona says, “studying public spaces offers a good surrogate for larger urban design processes”. Formulating a theoretical basis for urban design on the basis of studies of public space may define urban design too narrowly. Here are some examples of urban design that could require a different methodology.

Facing Up to Rising Sea Levels

The Royal Institute of British Architects’ Building Futures program and the Institution of Civil Engineers released a report in January 2010, ‘Facing Up to Rising Sea Levels: Retreat? Defence? Attack?’ This report looks at the 12,429 kilometers of coastline in the UK and documents an increasing risk of flooding as sea levels rise. The report includes designs for Hull and for Portsmouth

illustrating various strategies for dealing with this threat, from moving portions of a city away from the coast, improving sea walls and other defences, and actually building up and out over the water. Whatever you think about the risks and the design strategies, there is no question that this report is about urban design. The process diagram included in the report, Figure 1, shows how much more

complicated dealing with these types of issues has to be, compared with professor Carmona’s diagram of the forces involved in designing a public place.

The Thames Barrier as Urban Design

The Thames Barrier, completed in 1982, is an example of a defence strategy against flood surges that is already in operation. It may not come to mind immediately as an example of place-making, but, without it, London would certainly be turning into a very different city. According to the Environment Agency, the Barrier protects 125 square kilometers of London from flooding, and, as of October 2011,

the Barrier has had to be closed 119 times – not counting monthly closings for testing and maintenance. If there were no barrier, properties upstream from Woolwich Reach would need to be protected by individual barriers, or the buildings, streets and public places in the flood zone would need to be raised. It is hard to imagine what the cumulative effect of such decisions would be like. Studies are underway to enlarge the Barrier, to deal with expected rises in sea level by 2030. So here we have an example of a fundamental urban design decision, which may well have taken place without much consultation with people who call themselves urban designers. How does a situation like this, or the placing of a bridge, or the creation of a new container port, fit into a theory devised for

understanding the design of public spaces?

High Speed Rail in the UK as a Regional and Urban Design Influence

The proposed high speed rail lines in the UK raise all types of environmental and city design questions about the right of way, as well as larger regional questions concerning the long-term effect of improved communication on economic development for cities along the route. There are several sets of interrelated variables. For example, what is the long-term effect on the design and

development of the city of Sheffield depending on the location of the station on a future high-speed rail line: in the city center or at Sheffield Meadowhall? What is the design of the right of way going to be like as it enters and leaves the city, and how are negative effects of the track system going to be mitigated? How will development around the new station be managed? Big urban design questions,

within a decision-making structure where urban design may not be the primary consideration.

Managing Development Using Codes

A fundamental issue when codes are written to shape development is that it is not possible to know when the code is enacted which properties will develop, and which will not, nor is it possible to know in what order the places governed by the code are likely to develop. The urban design concept that is the basis for the code has to be valid no matter when or in what order the code is implemented.

An example is the management of a city’s skyline. At one end of the spectrum you have cities such as Washington DC which have strict overall height limits; at the other end is Manhattan, with many zones that permit tall buildings. Paris, with strong height limits in most places, and tall buildings segregated at La Defence, is close to the Washington end of the spectrum, while London – it seems to an

outsider – is drifting towards a Manhattan-like skyline, apparently without an inclusive design concept. Is this effect the result of over-decentralized design administration, or is there a different rationale that will become apparent in time?In any case, managing the skyline for a major city is an urban design problem whose resolution requires an interplay between real-estate market forces and place-making. These days solar and wind access have become additional elements.

Urban Design for Streets

Gehl Architects made an analysis of central London, Towards a Fine City for People: Public Spaces and Public Life, published in 2004. Much of Jan Gehl’s study was about streets. The study emphasized that London had increasingly been giving primacy to vehicular traffic, forcing pedestrians into underground crossings at big intersections, and putting railings along pavements to prevent jaywalking. Photos documented how pedestrians evaded these restrictions, getting past the railings to

52 J. Barnett make dangerous sprints across busy intersections, and then walking in the streets, outside the railings, looking for an opening to get back to the pavement. While London’s flat topography and moderate climate make it suitable for bicycles, Gehl found that little provision had been made for them in central London. Urban design for streets is different from the design of public places because it involves designing traffic patterns. Jan Gehl’s approach to understanding and shaping streets is to give priority to pedestrians, then bicycles, followed by transit, cars, freight and deliveries. Traffic planning has traditionally been an engineering discipline not involving urban designers. Gehl is very clear that designing for pedestrians and bicycles needs to have as strong an objective rationale as other types of traffic planning, and that means giving movement equal importance to the more stationary or localized experiences found in a public plaza. Other examples of urban design problems larger and more complex than an individual public space include the design of new communities, the reorganization of waterfronts, the design of large-scale developments such as

Canary Wharf, neighborhood revitalization and preservation of historic districts. For a theory of urban design to be comprehensive and consistent, it needs towork for the full range of urban design situations.