Traffic safety, usability and streetscape effects of new design principles for major urban roads

An important aspect of area-wide traffic calming concepts is the integration of major urban roads, because 70 to 80 percent of all urban accidents occur on major roads. Traffic calming which is primarily based on the locational shift to such main thoroughfares is socially injust, because -in spite of all disturbances on those streets about one quarter of the urban population live there. Social justice can only be somewhat achieved if the expenditures for traffic calming and streetscaping are not used -as today is most common -for accumulating the advantages in the low traffic side streets, but aimed at a partial balance and compensation for the strains caused by car traffic on the major streets. Some compensatory measures and new design principles will be discussed. Backgrounds are the experience in six German model cities of area-wide traffic calming, several research projects and the discussion about new guidelines for major urban roads. Where traffic and environmental burdens focus, the concentration concept should be extended by compensatory measures. That is the state of discussion in Germany examplified by nine topics. Where traffic and environmental burdens focus Since Buchanan's "Traffic in Towns" was published in 1963, the organization of urban road networks has been the concentration of car traffic on main roads, and the relief and reduction of traffic in the adjacent residential areas. Two coincidentally incompatible demands for reduction of car traffic on the one hand and for easy flow on the other hand were locationally separated and perfected -this applies to many measures of traffic reduction as well as for the one-sided car traffic oriented urban constructural devastation of many main thoroughfares. Traffic reduction which is primarily based on the locational shift of This is an edited version of a speech presented by the author at the International Conference "Living and Moving in Cities" in Paris, January 1990.