In this article, a novel technical treatment system for road runoff will be discussed. This system is based on a lamella separator and a combined sand adsorber layer. It is applied at three treatment sites along the highway A2. While the lamella separator and the sand layer are used for particle retention, the adsorber layer removes the dissolved heavy metals. Ferric hydroxides and zeolite were evaluated as adsorbents. The two adsorbents are placed below the sand layer and in separate basins. In order to assess the performance for each treatment component, a monitoring program will be performed at one of the three identical treatment sites.