In this project, existing environmentally sensitive traffic management (ETM) systems in Braunschweig, Erfurt, Potsdam and Wittenberg as well as a motorway traffic control system in Styria were selected for detailed investigations. The study shows that the ETM systems operate reliably and are accepted by public authorities, industry and private road users alike. They help to reduce air pollution and the measures implemented comply with the principle of proportionality. Based on operational data from the areas subject to investigation, it was possible to systematise and evaluate the effects of measures with regard to threshold values and traffic relocations. Changes in flow of traffic, journey times, emissions, road safety and concentrations were analysed as well. Furthermore, forecasts and levels of compliance were evaluated. For hot spots with an NO2 annual mean value close to the limit value, the reductions determined for soft measures, such as improving the flow of traffic and controlling the inflow of traffic, are in the single-digit percentage range. In terms of the number of days on which PM10 limit values were exceeded, a reduction of a few days was recorded. Higher rates of reduction can be achieved by stricter threshold values and/or introducing hard measures such as traffic restrictions or driving bans. For hot spots with considerable exceedances of limit values, only hard ETM measures lead to the desired results anyway. The environmentally sensitive approach allows threshold values and effects of measures to be optimised with respect to the targets. Cost and impact analyses show that the implemented ETM measures have either an overall positive cost-benefit ratio or are at least much more beneficial when comparing a dynamic activation with a permanent activation. Recommendations were given to the authorities on the design and use of ETM systems and measures, depending on local boundary conditions. (Author/publisher)
Abstract