Effective redesign and organisation of the inner-city street network through new forms of public participation.

The development of new urban areas has to be considered as a major challenge for the urban structure of a city. This is particularly true when looking at the consequences for urban transport systems and the effects for the entire street network. The paper presents the Ettlingen case of the conversion of former military barracks into a new urban development, describes the development concept and visualises how the concept deals with predicted higher traffic volumes and the restriction of traffic impacts on surrounding neighbourhoods especially when looking at consequences for vehicles kilometres travelled. Focus is laid on the cooperation with citizens, the communication platform to direct public opinions and the interaction with politics. The concept stipulated a carefully designed new street network based on a system of roundabouts. It aimed at giving priority to sustainable modes of transport (increased accessibility), improving overall road safety, reducing the impact of motorised traffic on other modes of transport and on the surroundings. As the new development structure filled an important gap within the city, a direct access to the main street network was created either from the new development areas or from an existing neighbourhood area. This was necessary in order to achieve a better distribution within the network and to avoid congestion of existing intersections. Consequently, accompanying traffic calming measures in the existing residential areas were required. The results showed a considerable improvement of transport conditions. This is due to remarkable reductions in overall traffic volumes and particularly within the surrounding neighbourhoods. Moreover, the new distribution of traffic and the creation of a direct access to the main street network did not produce any through traffic as was feared by the public. Moreover, the chosen strategy of voluntary public consultation contributed to reduce the number of objections and to save time instead. The outcome also permits a first discussion on the reasons for continuously decreasing traffic volumes as a previous traffic study has indicated already. Apart from local factors such as transport policy, overall traffic calming aspects like population aging and changing gasoline prices needed to be taken into account. For the covering abstract see ITRD E126595.