Increasing legal requirements for stormwater treatment in road construction measures ne-cessitate a continuous development of the systems for the treatment of traffic surface runoff. In particular on highly trafficked highways, the introduction of heavy metals and deicing salt into surface waters can have a potential adverse effect on the status of the water body. The first part of the thesis is therefore concerned with the development of measures to improve the heavy metal retention in stormwater basins. In the second part, measures are presented in order to even out and reduce the salt concentrations at the outlet of stormwater basins. In conclusion both partial results are summarized into a constructive overall concept. The evaluation of the drainage plans of the motorway section on the A 8 between Munich and Augsburg with 25 rainwater systems designed close to nature showed that the existing technical rules with recommendations for basin geometry are not consistently implemented. AS a result, the sedimentation potential of the basins is not fully exploited. In settling exper-iments, an increase in the rate of settling velocity of particles in the stormwater runoff with increasing salinity was successfully demonstrated, which was attributed to flocculation pro-cesses. With an adapted basin construction, by utilizing this effect, an improvement of the sedimentation performance, in particular in the case of the fine particle fraction, can be achieved. In addition, it was shown that the heavy metal components in the sediment which can be remobilized under reducing conditions are subject to an increased risk for remobili-zation during the deicing salt season, whereas the fraction which can be remobilised by cation exchange is only of minor relevance in this regard. To improve the deicing salt retention, five different basin designs with different bottom de-signs were developed. These were evaluated in terms of the deicing salt retention in simu-lation studies with the CFD software Telemac-Mascaret in different scenarios. For improved salt retention, a combination of two sub-basins, each with a deepening near the inlet, was recommended. The combination of the partial results with the two optimization targets of deicing salt and heavy metal retention results in a two-stage basin concept with a sole sloping down to the inlet. In addition, in the second stage, the installation of floating treatment wetlands for im-proved flow conditions is advised. The approaches to stormwater treatment presented in this work can make a decisive con-tribution to ensuring that the expected further increase in traffic volumes in Germany is not accompanied by a further deterioration in the status of surface waters.
«Increasing legal requirements for stormwater treatment in road construction measures ne-cessitate a continuous development of the systems for the treatment of traffic surface runoff. In particular on highly trafficked highways, the introduction of heavy metals and deicing salt into surface waters can have a potential adverse effect on the status of the water body. The first part of the thesis is therefore concerned with the development of measures to improve the heavy metal retention in stormwat...
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