Integration or Segregation ? Recommendations of the Principles of Urban Road Network Design for the Sustainable City

Integration or Segregation ? Recommendations of the Principles of Urban Road Network Design for the Sustainable City


Gustav Nielsen, Civitas AS, NO


The paper will review the current debate about the principles of urban road transport network design and analyse the merits of traffic integration and filtering of car traffic versus differentiation and segregation of different types of traffic.


The paper will deal with the current international debate about the principles of road and transport network design in urban areas, in particular the urbanist critique of the conventional approach in the tradition of the famous Buchanan report (Traffic in Towns 1963) and the influential Scandinavian traffic safety principles of SCAFT (1967). This is done through a literature-based review of the competing concepts of:
? Traffic integration and traffic calming with filtering of car traffic into the traditional, mixed use urban street as the main object of interest, versus
? Differentiation and segregation of different types of traffic, with the hierarchical road system as a main system solution, resulting in urban structures that are characteristic of the modernistic, car-based city.
The merits and disadvantages of the two different planning paradigms will be discussed in relation to the goal of sustainable development, and on the base of existing empirical evidence of the effects of the various types of solutions recommended by the different schools of thought. The paper will propose a revised set of network principles that might be recommended to cities that have a sustainable transport system as a major goal of city development and transport.

The paper will be based on a literature review on this topic that the author has carried out for the TRAST (Traffic for an attractive city) project of the Swedish Road Administration and other national bodies responsible for urban planning and transport in Sweden. The finally revised report (in English) is due to be completed in February/March 2006.

A preliminary outline of the paper:
? Defining the goal of sustainable urban transport
? A short history of the urban network design principles and their different ways of accommodating car traffic growth in urban areas
? The urbanist critique of conventional road planning and modernistic urban design
? The alternative principles proposed; traffic integration and car traffic filtering
? Some important facts about the interactions between land use, car traffic, urban environment and traffic safety
? A discussion of the consequences of alternative network strategies for urban sustainability
? Conclusions: Some principles of network design for the sustainable city

Project background
The study is one of several other analyses of different aspects of urban road transport network design that are being made as part of the revision of the Swedish design guides for urban road transport system design. The development programme called TRAST (Traffic for an attractive city) is a joint venture of the Swedish Road Administration, the Swedish Rail Administration ? Banverket, the Swedish Association of Local Authorities and Regions and the National Board of Housing, Building and Planning ? Boverket.

More information about TRAST on the project website (in Swedish):


Association for European Transport